Distortion — effect atlas¶
8 effects · 773 captures. Waveshapers, amp simulators and combined distortion chains. Two independent methods agree here: harmonic pre-echoes from the log sweep, and a two-tone probe stepped through four input levels.
Part of the Motif ES effects teardown; the method and the cross-effect findings are in the main analysis (notebook).
How to read a card¶
Each effect gets one card, then a written breakdown.
- Header band. The effect's name, category, how many recordings exist, and a one-sentence summary written from the measurements.
- Tiles. The handful of numbers that matter most for this type of effect, at default settings. A dash means the value could not be measured, and the small caption says why.
- The knob console. One knob per control. Click a knob to select it and move the slider under the knobs to turn it. A knob's ring is its own travel, coloured stretch by stretch: green where turning it barely changes the sound, red where a small turn changes it a lot, grey where nothing measurable happens. A knob outlined in cyan was also recorded together with the selected one, and its ring changes as the slider moves; every other ring shows that knob with the rest at their defaults. Controls that showed no measurable change at all are listed under the console, not drawn.
- What each knob does. One bar per control, longest first. Bar length is the size of the change the knob makes, in multiples of the smallest change that matters in practice (1 dB of level, 20% of decay time, 10% of LFO rate…), on a log scale. Colour says what kind of change. ◆ marks readings taken with a test sound designed for that knob. Grey dots are knobs that did nothing with the other controls at default.
- Signature panel. The view that best explains this kind of effect: decay curves for a reverb, echo taps for a delay, the input/output curve for a compressor, harmonics against input level for a distortion, the LFO for a modulation effect.
- Knob × frequency. Each row is one knob at one tested setting; red means louder than default at that frequency, blue quieter. Modulation effects get a what the knobs touch matrix instead, because a running LFO has no single frequency response.
- Stereo. How the left and right inputs reach the outputs.
The breakdown under each card notes the structure the measurements reveal, flags caveats, and
names the tests in TESTS_NEEDED.md that would complete the picture. Below it, every knob is
charted with the range tested and what it does; hover a bar for the detail.
Show code
import warnings; warnings.filterwarnings("ignore")
import sys; sys.path.insert(0, "..")
import os; os.chdir("..") # the cache lives in the project root
import matplotlib.pyplot as plt
from IPython.display import HTML, Markdown, display
import load, knobs, cards, plots, iviz, gapfill, knobviz, vizstyle as V
V.setup()
from matplotlib_inline.backend_inline import set_matplotlib_formats
set_matplotlib_formats("svg") # figures embed as vector, not PNG
display(iviz.page_css())
df, curves = load.load()
noise = knobs.noise_table(df, curves)
g = gapfill.load()
def show(fig):
display(fig)
plt.close(fig)
def show_card(effect):
show(cards.effect_card(df, curves, effect, noise)[0])
def show_knobs(effect):
board = knobviz.console(df, curves, effect, noise)
if board is not None:
display(board)
_, main, rh = cards.merged_knobs(df, curves, effect, noise)
for h in iviz.knob_plots(effect, main, rh):
display(h)
def show_parts(parts):
for f, note in parts: # each chart, then its own explanation directly under it
f.show()
display(Markdown(note))
def show_gapfill(effect, stimuli=None, drives_only=False):
parts = iviz.gf_effect_parts(g, effect, stimuli, drives_only)
if parts:
display(Markdown(iviz.GF_INTRO))
show_parts(parts)
The family at a glance¶
Every effect in the category on the same few numbers, then all of them on one chart — drag the slider to bring one forward, hover for exact values.
Show code
knob_counts = {'Amp Sim 2': (5, 0), 'Amp Simulator': (5, 0), 'Comp + Dist': (11, 2), 'Dist + Delay': (10, 0), 'Distortion': (7, 1), 'Odrv + Delay': (10, 0), 'Overdrive': (7, 2), 'V-Distortion': (10, 2)}
show(cards.family_overview(df, 'Distortion', knob_counts, curves))
Show code
iviz.family_fig(df, curves, 'Distortion').show()
Recap. Why: to compare the tone of every effect in the family on one chart. How to read it: each line is one effect's frequency response, centred on its own median; drag the slider to bring one forward, hover for exact values.
Technical explanation. Each effect's frequency response at the capture baseline — how much each frequency is boosted or cut on its way through — measured by log-sweep deconvolution, smoothed to 1/6 octave, averaged over repeat captures, and shifted to its own median so the chart compares tone shape, not loudness. Drag the slider to bring one effect forward. The chart below this text reads each curve off as three numbers: its peak, the range within 6 dB of the peak, and the span from peak to deepest cut.
Identical curves (under 0.5 dB apart), so the same processing at these settings — a shared tone stage, or, for an EQ left flat, no shaping beyond the capture chain: Comp + Dist = Distortion; Odrv + Delay = Overdrive. A presence peak between 2 and 8 kHz with a steep cut above it (a speaker-cabinet shape): Amp Sim 2, Amp Simulator, Comp + Dist, Dist + Delay, Distortion, Odrv + Delay, Overdrive. Less reliable in detail (repeat captures differ by over 3 dB, usually a running LFO): Amp Sim 2. Not shown: level (each curve is centred on its own median), anything that changes over time, and the harmonics themselves, which the log sweep separates out (they are in the harmonics panels).
Plain explanation: this is the effect's tone — which parts of the sound it makes louder or quieter. Curves that overlap exactly mean those effects do the same thing to your tone at these settings. A bump in the upper mids followed by a steep drop is what a guitar speaker does: it adds bite and removes harsh fizz. Comp + Dist, Distortion, Odrv + Delay and Overdrive roll off the top end early, so they sound darker.
In other words, the main points:
- Most shaping: Overdrive, 24 dB from peak to deepest cut.
- Same tone curve (within 0.5 dB): Comp + Dist = Distortion; Odrv + Delay = Overdrive.
- Speaker-cabinet shape (presence peak, steep cut above it): Amp Sim 2, Amp Simulator, Comp + Dist, Dist + Delay, Distortion, Odrv + Delay, Overdrive.
- Darkest (top end rolled off early): Comp + Dist, Distortion, Odrv + Delay, Overdrive.
- Least repeatable in detail (usually a running LFO): Amp Sim 2.
Show code
iviz.tone_bands(df, curves, 'Distortion')
Where the clipping starts, and what it does to bass and treble¶
Recap · Why: one test level cannot show where a distortion starts to clip, and one test note cannot show whether it treats bass and treble alike. The two-tone ladder plays two notes together at ten levels over 54 dB, at each Drive setting; the tone triplet plays 100 Hz, 1 kHz and 5 kHz at one level, then a deliberately lopsided wave.
How to read it: first, intermodulation against input level, one line per Drive setting; second, the same reading at −30 dBFS for every drive control; then bars per effect, where taller means more distortion.
Technical explanation. With Drive at 0 the Distortion's intermodulation at −30 dBFS is -86 dB; by raw 31 it is within 3 dB of its ceiling of -10.2 dB, and more Drive changes nothing at this level. Distortion, Overdrive and Amp Simulator trace the same ladder to within 0.2 dB at every Drive step above zero: another independent sign of one shared clipping stage. At −16 dBFS and default settings those three read -7.4 dB THD at 100 Hz, -10.8 dB at 1 kHz and -36.1 dB at 5 kHz: the harmonics of a 5 kHz note fall above the tone filter that follows the clipper, so they are filtered out, not absent. Fed a sine plus its own second harmonic they change the second harmonic by -2.7 dB and add a third at -16 dB, consistent with symmetric clipping. Harmonic Enhancer does the opposite: it raises the second harmonic by +11.8 dB, leaves a 100 Hz sine clean (-76 dB THD) and works on 1 kHz and above (-39 dB).
Plain explanation: turn Drive up from zero and the grit arrives almost at once: by 31 of 127 the effect is as distorted as it gets on a normal-level signal. Low notes come out dirtier than high ones, because the tone filter after the clipper removes the fizz from high notes. The Harmonic Enhancer is not a distortion in this sense: it adds a gentle octave-up shimmer to the upper part of the sound and leaves the bass alone.
In other words, the main points:
- Intermodulation at −30 dBFS climbs from -86 dB at Drive 0 to a ceiling of -10.2 dB, reached by raw 31.
- Distortion, Overdrive and Amp Simulator match within 0.2 dB at every Drive step: one clipping stage.
- THD by frequency at default: -7.4 dB at 100 Hz, -10.8 dB at 1 kHz, -36.1 dB at 5 kHz (the tone filter removes a high note's harmonics).
- Harmonic Enhancer adds +11.8 dB of second harmonic and leaves 100 Hz clean.
Show code
show_parts(iviz.probe_parts(g, 'distortion'))
What it shows. Two notes played together (220 and 697 Hz) at ten levels from −60 to −6 dBFS through Distortion, once for each Drive setting.
How to read it. Input level left to right; upward is how loud the extra tones created between the two notes are, against the notes themselves. Higher means harsher chords.
What it found.
- With Drive at 0 the pair stays clean (−86 dB at −30 dBFS) until the loudest step.
- By raw 31 it is within 3 dB of the ceiling of −10.2 dB at that level.
What it shows. The same reading at −30 dBFS for every drive control on every effect that has one.
How to read it. Each line is one drive control, from the bottom of its travel (left) to the top (right); colour is the effect family. Hover a line for the effect and control.
What it found.
- Distortion, Overdrive and Amp Simulator trace the same line within 0.2 dB: one shared clipping stage.
What it shows. One sine at −16 dBFS at 100 Hz, 1 kHz and 5 kHz through each distortion at its default settings.
How to read it. Three bars per effect; taller means more harmonic distortion (0 dB would be overtones as loud as the note).
What it found.
- The hard clippers read −7.4 dB at 100 Hz, −10.8 dB at 1 kHz and −36.1 dB at 5 kHz: the tone filter after the clipper removes a high note's overtones.
What it shows. A deliberately lopsided wave (a sine plus its own 2nd harmonic) through each effect.
How to read it. The bar is how much the 2nd harmonic changed against the note. Below zero the effect reduced it, above zero it added more.
What it found.
- The hard clippers lower it by 2.7 dB, as a symmetric clipper does; Harmonic Enhancer raises it by 11.8 dB.
Saturation texture: harmonics against drive, and what two notes make together¶
A single distortion figure hides which harmonics are added and when. Each matrix below lays out the 2nd to 9th harmonic at every drive setting; the dot maps after them show the extra tones created between two notes, which a single test tone cannot reveal.
Show code
import kinetics, kviz, wviz, rviz
show_parts(wviz.wave_parts(g) + kviz.distortion_parts(kinetics.load(), g) + kviz.distortion_second_parts(g))
What it shows. Two cycles of a 100 Hz sine at −6 dBFS as each distortion returns them, averaged over about 150 cycles, at five drive settings (cyan lowest, amber highest). The dotted line is the sine that went in.
How to read it. A clean effect lies on the dotted line. Flat tops are clipping: the wider the flat part, the harder the clip. Sloping or dented tops come from the tone filters around the clipper. If the upper and lower halves are different shapes, the effect treats the two directions differently, which is what adds even harmonics. Use the slider to change effect.
What it found.
- At full drive the wave spends this share of each cycle within a tenth of its peak (a sine spends 29% there): Dist + Delay 98%, Comp + Dist 97%, Distortion 97%, Odrv + Delay 97%, Overdrive 97%, Amp Sim 2 96%, Amp Simulator 73%, V-Distortion 63%.
- The two halves differ most on Amp Sim 2 (their averages are off balance by 0.04 of the peak) and least on Overdrive (0.00).
What it shows. The 2nd to 9th harmonics Amp Sim 2 adds to a 100 Hz sine at −6 dBFS, at 9 settings of Drive.
How to read it. The drive setting runs left to right, the harmonic number upward; brighter amber is a louder harmonic and each cell shows its level in dB below the 100 Hz note. A column that stops changing is a setting past which the clipper is already saturated.
What it found.
- Distortion is 1.63% at
Drive0 and 43% at 127; it is within 1 dB of its ceiling byDrive47, so the rest of the control's travel adds little. - The strongest harmonic at full drive is the 3rd at −10 dB; odd harmonics lead even ones by 44 dB at full drive (symmetric clipping).
What it shows. The 2nd to 9th harmonics Amp Simulator adds to a 100 Hz sine at −6 dBFS, at 9 settings of Drive.
How to read it. The drive setting runs left to right, the harmonic number upward; brighter amber is a louder harmonic and each cell shows its level in dB below the 100 Hz note. A column that stops changing is a setting past which the clipper is already saturated.
What it found.
- Distortion is 0.01% at
Drive0 and 41% at 127; it is within 1 dB of its ceiling byDrive15, so the rest of the control's travel adds little. - The strongest harmonic at full drive is the 3rd at −10 dB; odd harmonics lead even ones by 35 dB at full drive (symmetric clipping).
- The 2nd harmonic climbs 46 dB across the range while staying far below the odd ones.
What it shows. The 2nd to 9th harmonics Comp + Dist adds to a 100 Hz sine at −6 dBFS, at 9 settings of Drive.
How to read it. The drive setting runs left to right, the harmonic number upward; brighter amber is a louder harmonic and each cell shows its level in dB below the 100 Hz note. A column that stops changing is a setting past which the clipper is already saturated.
What it found.
- Distortion is 0.01% at
Drive0 and 43% at 127; it is within 1 dB of its ceiling byDrive31, so the rest of the control's travel adds little. - The strongest harmonic at full drive is the 3rd at −10 dB; odd harmonics lead even ones by 52 dB at full drive (symmetric clipping).
- The 2nd harmonic climbs 34 dB across the range while staying far below the odd ones.
What it shows. The 2nd to 9th harmonics Dist + Delay adds to a 100 Hz sine at −6 dBFS, at 9 settings of Dist-Drive.
How to read it. The drive setting runs left to right, the harmonic number upward; brighter amber is a louder harmonic and each cell shows its level in dB below the 100 Hz note. A column that stops changing is a setting past which the clipper is already saturated.
What it found.
- Distortion is 0.01% at
Dist-Drive0 and 40% at 127; it is within 1 dB of its ceiling byDist-Drive31, so the rest of the control's travel adds little. - The strongest harmonic at full drive is the 3rd at −10 dB; odd harmonics lead even ones by 50 dB at full drive (symmetric clipping).
- The 2nd harmonic climbs 22 dB across the range while staying far below the odd ones.
What it shows. The 2nd to 9th harmonics Distortion adds to a 100 Hz sine at −6 dBFS, at 9 settings of Drive.
How to read it. The drive setting runs left to right, the harmonic number upward; brighter amber is a louder harmonic and each cell shows its level in dB below the 100 Hz note. A column that stops changing is a setting past which the clipper is already saturated.
What it found.
- Distortion is 0.01% at
Drive0 and 45% at 127; it is within 1 dB of its ceiling byDrive31, so the rest of the control's travel adds little. - The strongest harmonic at full drive is the 3rd at −9 dB; odd harmonics lead even ones by 37 dB at full drive (symmetric clipping).
- The 2nd harmonic climbs 45 dB across the range while staying far below the odd ones.
What it shows. The 2nd to 9th harmonics Odrv + Delay adds to a 100 Hz sine at −6 dBFS, at 9 settings of Dist-Drive.
How to read it. The drive setting runs left to right, the harmonic number upward; brighter amber is a louder harmonic and each cell shows its level in dB below the 100 Hz note. A column that stops changing is a setting past which the clipper is already saturated.
What it found.
- Distortion is 0.01% at
Dist-Drive0 and 40% at 127; it is within 1 dB of its ceiling byDist-Drive15, so the rest of the control's travel adds little. - The strongest harmonic at full drive is the 3rd at −10 dB; odd harmonics lead even ones by 35 dB at full drive (symmetric clipping).
- The 2nd harmonic climbs 34 dB across the range while staying far below the odd ones.
What it shows. The 2nd to 9th harmonics Overdrive adds to a 100 Hz sine at −6 dBFS, at 9 settings of Drive.
How to read it. The drive setting runs left to right, the harmonic number upward; brighter amber is a louder harmonic and each cell shows its level in dB below the 100 Hz note. A column that stops changing is a setting past which the clipper is already saturated.
What it found.
- Distortion is 0.01% at
Drive0 and 41% at 127; it is within 1 dB of its ceiling byDrive31, so the rest of the control's travel adds little. - The strongest harmonic at full drive is the 3rd at −10 dB; odd harmonics lead even ones by 50 dB at full drive (symmetric clipping).
- The 2nd harmonic climbs 29 dB across the range while staying far below the odd ones.
What it shows. The 2nd to 9th harmonics V-Distortion adds to a 100 Hz sine at −6 dBFS, at 9 settings of Over-Drive.
How to read it. The drive setting runs left to right, the harmonic number upward; brighter amber is a louder harmonic and each cell shows its level in dB below the 100 Hz note. A column that stops changing is a setting past which the clipper is already saturated.
What it found.
- Distortion is 0.01% at
Over-Drive0 and 38% at 100; it is within 1 dB of its ceiling byOver-Drive37, so the rest of the control's travel adds little. - The strongest harmonic at full drive is the 3rd at −11 dB; odd harmonics lead even ones by 41 dB at full drive (symmetric clipping).
- The 2nd harmonic climbs 26 dB across the range while staying far below the odd ones.
What it shows. Two notes, 220 Hz and 697 Hz, played together through Distortion at ten levels. Each dot is a tone the effect added that was not played: amber for sums and differences of the two notes (intermodulation), cyan for harmonics of one note alone. 54 possible products up to the 7th order are checked at every level.
How to read it. Frequency runs left to right, input level upward; a bigger, brighter dot is a louder product (hover for its level and the arithmetic behind its frequency). The white diamonds are the two notes. Drag the slider to change Drive. Products within 6 dB of the noise beside them are left out.
What it found.
- At
Drive0 there are 45 measurable products at −6 dBFS and 0 at −42 dBFS; atDrive127 there are 48 and 52. - Unlike the compressor chains on the Dynamic page, a row that empties toward the bottom is a distortion that cleans up when played softly.
What it shows. Two notes, 220 Hz and 697 Hz, played together through Amp Sim 2 at ten levels. Each dot is a tone the effect added that was not played: amber for sums and differences of the two notes (intermodulation), cyan for harmonics of one note alone. 54 possible products up to the 7th order are checked at every level.
How to read it. Frequency runs left to right, input level upward; a bigger, brighter dot is a louder product (hover for its level and the arithmetic behind its frequency). The white diamonds are the two notes. Drag the slider to change Drive. Products within 6 dB of the noise beside them are left out.
What it found.
- At
Drive0 there are 10 measurable products at −6 dBFS and 3 at −42 dBFS; atDrive127 there are 43 and 52. - Unlike the compressor chains on the Dynamic page, a row that empties toward the bottom is a distortion that cleans up when played softly.
What it shows. Two notes, 220 Hz and 697 Hz, played together through V-Distortion at ten levels. Each dot is a tone the effect added that was not played: amber for sums and differences of the two notes (intermodulation), cyan for harmonics of one note alone. 54 possible products up to the 7th order are checked at every level.
How to read it. Frequency runs left to right, input level upward; a bigger, brighter dot is a louder product (hover for its level and the arithmetic behind its frequency). The white diamonds are the two notes. Drag the slider to change Over-Drive. Products within 6 dB of the noise beside them are left out.
What it found.
- At
Over-Drive0 there are 8 measurable products at −6 dBFS and 4 at −42 dBFS; atOver-Drive100 there are 49 and 43. - Unlike the compressor chains on the Dynamic page, a row that empties toward the bottom is a distortion that cleans up when played softly.
What it shows. A 1 kHz tone rising smoothly from −69 to −4 dBFS through each distortion at five drive settings (cyan lowest, amber highest), read every decibel: everything in the output that is not the 1 kHz note, relative to the note.
How to read it. Lower is cleaner. The steady fall on the left is the noise floor being left behind as the note gets louder. The rise is the onset of clipping; a short steep rise is a hard knee, a long gradual one a soft knee.
What it found.
- Amp Sim 2: −10 dB once saturated; at
Drive31 the ceiling is reached at −21 dBFS in; at the lowest setting the residue is −34 dB at −4 dBFS in; Amp Simulator: −11 dB once saturated; atDrive31 the ceiling is reached at −34 dBFS in; at the lowest setting the residue is −51 dB at −4 dBFS in; Comp + Dist: −11 dB once saturated; atDrive31 the ceiling is reached at −37 dBFS in; at the lowest setting the residue is −67 dB at −4 dBFS in; Dist + Delay: −8 dB once saturated; atDist-Drive31 the ceiling is reached at −37 dBFS in; at the lowest setting the residue is −22 dB at −4 dBFS in; Distortion: −11 dB once saturated; atDrive31 the ceiling is reached at −34 dBFS in; at the lowest setting the residue is −53 dB at −4 dBFS in; Odrv + Delay: −11 dB once saturated; atDist-Drive31 the ceiling is reached at −36 dBFS in; at the lowest setting the residue is −24 dB at −4 dBFS in; Overdrive: −11 dB once saturated; atDrive31 the ceiling is reached at −33 dBFS in; at the lowest setting the residue is −61 dB at −4 dBFS in; V-Distortion: −5 dB once saturated; atOver-Drive25 the ceiling is reached at −21 dBFS in; at the lowest setting the residue is −61 dB at −4 dBFS in. - The left-hand part of every line, falling at 1 dB per dB, is noise and not distortion; the bypass line shows where that floor lies.
What it shows. Sixteen notes from 55 Hz to 7 kHz, each at −12 dBFS, through each distortion at its highest drive setting: the level of the 2nd to 7th harmonic of every note.
How to read it. The note played runs left to right, the harmonic number upward; brighter amber is a louder harmonic and the number is its level in dB below the note. Blank cells are harmonics that would lie above 20 kHz. A row that fades to the right is a harmonic removed by filtering after the clipper. Use the slider to change effect.
What it found.
- Amp Sim 2: 3rd harmonic −10 dB on notes up to 500 Hz, strongest even harmonic −66 dB, 3rd harmonic of a 2.4 kHz note −14 dB; Amp Simulator: 3rd harmonic −10 dB on notes up to 500 Hz, strongest even harmonic −65 dB, 3rd harmonic of a 2.4 kHz note −19 dB; Comp + Dist: 3rd harmonic −10 dB on notes up to 500 Hz, strongest even harmonic −82 dB, 3rd harmonic of a 2.4 kHz note −19 dB; Dist + Delay: 3rd harmonic −10 dB on notes up to 500 Hz, strongest even harmonic −57 dB, 3rd harmonic of a 2.4 kHz note −10 dB; Distortion: 3rd harmonic −10 dB on notes up to 500 Hz, strongest even harmonic −79 dB, 3rd harmonic of a 2.4 kHz note −19 dB; Odrv + Delay: 3rd harmonic −10 dB on notes up to 500 Hz, strongest even harmonic −58 dB, 3rd harmonic of a 2.4 kHz note −19 dB; Overdrive: 3rd harmonic −10 dB on notes up to 500 Hz, strongest even harmonic −87 dB, 3rd harmonic of a 2.4 kHz note −19 dB; V-Distortion: 3rd harmonic −10 dB on notes up to 500 Hz, strongest even harmonic −48 dB, 3rd harmonic of a 2.4 kHz note −9 dB. Where the even harmonics sit 60 dB or more below the odd ones at every pitch, the clipping curve is symmetric across the whole keyboard; a 3rd harmonic that falls away at high notes is the tone filter after the clipper, not a cleaner clip.
What it shows. Four high notes (3.3, 6.5, 9.7 and 13.1 kHz at −6 dBFS) through each distortion at its highest drive. The chart shows the total level of everything in the output that is neither the note nor one of its true harmonics.
How to read it. The note played runs left to right; upward is more unrelated energy, in dB relative to the note itself. Above 0 dB the unrelated tones are louder than the note.
What it found.
- Unrelated energy rises with pitch in every effect and overtakes the note in most: at 13.1 kHz it reaches +16 dB in Odrv + Delay.
- A clipper makes harmonics at 3, 5, 7… times the note; for a 13.1 kHz note those would be at 39, 65, 92 kHz, which a 44.1 kHz system cannot represent.
- With no oversampling they are not removed, they reflect back into the audible range.
What it shows. The individual lines behind the chart above: every spectral line within 60 dB of the note, for each of the four notes.
How to read it. One column of dots per note; height is the line's frequency, size its level. Violet dots are true harmonics, amber dots are lines at frequencies unrelated to the note. Hover an amber dot for which harmonic it is and how many times it has folded. Use the slider to change effect.
What it found.
- 218 of the 404 unrelated lines across the eight effects match a harmonic of the note reflected off 44.1 kHz (within 25 Hz of |k × 44,100 − n × note|).
- The strongest in Distortion is harmonic 3 of the 13.1 kHz note, which should be at 39.3 kHz and appears at 4,800 Hz, +12 dB relative to the note.
- This is the harshness of older digital distortion on high notes: tones below the note that follow no musical relation to it.
What it shows. A 60 Hz note and a 7 kHz note played together (the bass four times the level of the treble, the standard SMPTE test), at eight levels, through each distortion at its highest drive. The reading is the energy that appears 60, 120 and 180 Hz either side of the treble note, relative to the treble note.
How to read it. Level runs left to right; upward means the bass is chopping the treble harder. At 0 dB the sidebands carry as much energy as the treble note itself. The dotted line is bypass (its left-hand end is noise).
What it found.
- Amp Sim 2 reaches +3 dB at −6 dBFS and passes −20 dB by −48 dBFS; Amp Simulator reaches +3 dB at −6 dBFS and passes −20 dB by −48 dBFS; Comp + Dist reaches +3 dB at −6 dBFS and passes −20 dB by −48 dBFS; Dist + Delay reaches +2 dB at −6 dBFS and passes −20 dB by −48 dBFS; Distortion reaches +3 dB at −6 dBFS and passes −20 dB by −48 dBFS; Odrv + Delay reaches +2 dB at −6 dBFS and passes −20 dB by −48 dBFS; Overdrive reaches +3 dB at −6 dBFS and passes −20 dB by −48 dBFS; V-Distortion reaches −2 dB at −6 dBFS and passes −20 dB by −42 dBFS. In Amp Sim 2, Amp Simulator, Comp + Dist, Dist + Delay, Distortion, Odrv + Delay, Overdrive the sidebands exceed the treble note: the bass note switches the treble on and off twice per cycle, which is the muddiness of a distorted chord with a low root.
What it shows. The same test on the Distortion effect alone, at five settings of Drive.
How to read it. As above, one line per drive setting (cyan lowest, amber highest).
What it found.
- At
Drive0 the reading stays at the bypass floor: no interaction between the notes. - From
Drive31 up it reaches the same ceiling, only at a lower level each time. - The clipper does not treat the two notes separately at any drive setting where it clips at all.
What it shows. One cycle of a 100 Hz sine at −6 dBFS through each distortion: the output plotted against the input at the same moment, averaged over about 150 cycles, at five drive settings (cyan lowest, amber highest). The output is scaled to its own peak.
How to read it. A clean effect draws the dotted diagonal. A clipper bends the ends of the line flat. If the line opens into a loop, the output is not a function of the input alone at that instant: something with memory (a filter before or after the clipper) is shifting the wave in time. A wide loop is a lot of phase shift at 100 Hz and its harmonics. Use the slider to change effect.
What it found.
- No effect opens into a loop: the output on the way up and on the way down differ by at most 1.31 of the peak (V-Distortion 1.31, Amp Sim 2 0.58, Amp Simulator 0.18 are the largest), about the thickness of the traced line.
- At 100 Hz each of these clippers is a fixed curve with no memory, in agreement with the timing takes, which found no attack or release.
What it shows. The frequency response of Amp Simulator at each AMP Type setting, measured with the drive turned to its minimum so the clipper is out of the way, and divided by the bypass response. The curves are matched in level at 300 Hz so their shapes can be compared.
How to read it. Frequency runs left to right on a musical scale, level upward. Each line is one voicing: this is the fixed equaliser that gives the model its character before any distortion is added.
What it found.
- Between 60 Hz and 6 kHz the 4 settings vary by 12 to 22 dB from their quietest to their loudest frequency.
- The strongest peak is setting 1's, +5 dB at 2,973 Hz.
- Above about 5 kHz every setting rolls off steeply: the cabinet's treble cut.
What it shows. The frequency response of Amp Sim 2 at each AMP Type setting, measured with the drive turned to its minimum so the clipper is out of the way, and divided by the bypass response. The curves are matched in level at 300 Hz so their shapes can be compared.
How to read it. Frequency runs left to right on a musical scale, level upward. Each line is one voicing: this is the fixed equaliser that gives the model its character before any distortion is added.
What it found.
- Between 60 Hz and 6 kHz the 7 settings vary by 7 to 18 dB from their quietest to their loudest frequency.
- The strongest peak is setting 4's, +6 dB at 2,123 Hz.
- Above about 5 kHz every setting rolls off steeply: the cabinet's treble cut.
What it shows. The frequency response of V-Distortion at each Device setting, measured with the drive turned to its minimum so the clipper is out of the way, and divided by the bypass response. The curves are matched in level at 300 Hz so their shapes can be compared.
How to read it. Frequency runs left to right on a musical scale, level upward. Each line is one voicing: this is the fixed equaliser that gives the model its character before any distortion is added.
What it found.
- Between 60 Hz and 6 kHz the 5 settings vary by 2 to 22 dB from their quietest to their loudest frequency.
- The strongest peak is setting 2's, +3 dB at 774 Hz.
- Above about 5 kHz every setting rolls off steeply: the cabinet's treble cut.
What it shows. The frequency response of V-Distortion at each Speaker Type setting, measured with the drive turned to its minimum so the clipper is out of the way, and divided by the bypass response. The curves are matched in level at 300 Hz so their shapes can be compared.
How to read it. Frequency runs left to right on a musical scale, level upward. Each line is one voicing: this is the fixed equaliser that gives the model its character before any distortion is added.
What it found.
- Between 60 Hz and 6 kHz the 6 settings vary by 2 to 44 dB from their quietest to their loudest frequency.
- The strongest peak is setting 5's, +24 dB at 5,449 Hz.
- Above about 5 kHz every setting rolls off steeply: the cabinet's treble cut.
What it shows. How far each distortion effect rotates the phase of a sound at each frequency, with the drive at minimum, relative to bypass. A plain delay (phase falling in proportion to frequency, fitted between 80 Hz and 5 kHz) is removed, and each curve is set to 0° at 300 Hz, so what is left is the bending of phase by the effect's filters.
How to read it. Frequency runs outward from the centre (40 Hz) to the rim (8 kHz); the angle is the phase shift. An effect with no filtering would draw a straight spoke at 0°. A line that swings away from that spoke is rotating some frequencies against others.
What it found.
- Amp Sim 2: −15° at 100 Hz, −18° at 1 kHz, −5° at 4 kHz; Amp Simulator: −17° at 100 Hz, −15° at 1 kHz, −6° at 4 kHz; Comp + Dist: −9° at 100 Hz, −16° at 1 kHz, −4° at 4 kHz; Dist + Delay: −4° at 100 Hz, −15° at 1 kHz, −1° at 4 kHz; Distortion: −8° at 100 Hz, −16° at 1 kHz, −4° at 4 kHz; Odrv + Delay: −2° at 100 Hz, −22° at 1 kHz, +1° at 4 kHz; Overdrive: −2° at 100 Hz, −22° at 1 kHz, +1° at 4 kHz; V-Distortion: +37° at 100 Hz, −17° at 1 kHz, +17° at 4 kHz.
- These rotations come with the tone-shaping filters shown above.
- They do not change the level of a single note, but they change how the effect's output adds to anything it is mixed with.
- The delay that was removed is a fit, so a few tens of degrees of the remaining swing at the top of the range could equally be described as delay.
Amp Sim 2¶
Show code
show_card('Amp Sim 2')
Amp Sim 2: what the measurements say¶
Recap. A distortion stage with 5 tested controls, 5 of which measurably change the sound. Beyond mix and level, the biggest lever is Drive: gain compression across the input range 0.0 → -18.4 dB. Measured with 52 captures: 28 on the main sweep + tone probe (one control at a time), 12 on matched probes (spectralSweep ×7, harmonicTwoTone ×5), 12 two-control pairs.
Technical explanation. At default settings: output -19.2 dBFS RMS (crest 8.2 dB); stereo width 0.02, L/R correlation +1.00; spectral tilt +0.17 dB/octave; 97% of the impulse response's energy in its first 5 ms; harmonics H2 -39 dB, H3 -9 dB re the linear response.
Structure:
- at full input: H2 -53 dB, H3 -35 dB, H4 -37 dB, H5 -22 dB, H6 -57 dB
- THD -26.3 dB at the quietest burst → -22.1 dB at the loudest; intermodulation -7.4 dB
Two-control pairs captured: AMP Type×LPF Cutoff, Drive×AMP Type, Drive×LPF Cutoff (interaction analysis in the main notebook).
Caveats:
- some long settings decay more slowly than the recording allows; their T30 is a lower bound
- at least one setting mutes the output; those captures are excluded from spectral analysis
Plain explanation: The control to reach for first is Drive: gain compression across the input range 0.0 → -18.4 dB. After that, AMP Type and LPF Cutoff make the next biggest differences. Output Level and DryWet set how much of the effect you hear and how loud it is. At default the output is close to mono.
In other words, the main points:
- 5 of 5 tested controls measurably change the sound.
- Biggest lever beyond mix and level: Drive, 18.4× the smallest change that matters (gain compression across the input range 0.0 → -18.4 dB).
- At default: stereo width 0.02, output -19.2 dBFS RMS.
- Main caveat: some long settings decay more slowly than the recording allows; their T30 is a lower bound.
- Still to measure: T1, T3, T4 (see
TESTS_NEEDED.md).
Show code
show_knobs('Amp Sim 2')
Gap Fill: each control in physical units¶
Every control stepped on a probe matched to what it does (17 steps for time and rate controls, 9 for the rest), read as the physical quantity it sets: how far a delay tap moves, level or treble lost per repeat, LFO rate and pitch swing, gate length, THD, intermodulation, compressor ratio, knee, attack and release, and where a gate opens and closes. Times are read inside one capture (channel against channel) because Gap Fill runs fully wet and file starts wander by about ±50 ms.
Show code
show_gapfill('Amp Sim 2')
How to read these charts. Each chart is one control. Left to right is the control's raw value as sent to the Motif (low to high setting); the height of the line is the physical quantity that control sets, measured from the recording. The title names the control, then the test signal used.
AMP-Type · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -6.73 at raw 0 to -8.75 at raw 6, dipping to -14.1.
AMP-Type · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -10.8 at raw 0 to -9.2 at raw 6, dipping to -12.1.
Drive · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -35.8 at raw 0 to -7.42 at raw 127.
Drive · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -55.3 at raw 0 to -10.2 at raw 127.
LPF-Cutoff · pinkPluck. Played: pink-noise bursts at three levels, then plucked notes. The line is Hz spectral centroid: the spectrum's centre of gravity, a measure of brightness; higher means brighter; here it goes from 571 at raw 0 to 3,991 at raw 60.
Amp Simulator¶
Show code
show_card('Amp Simulator')
Amp Simulator: what the measurements say¶
Recap. A distortion stage with 6 tested controls, 5 of which measurably change the sound. Beyond mix and level, the biggest lever is Drive: THD at full input -104 → -21 dB. Measured with 68 captures: 30 on the main sweep + tone probe (one control at a time), 14 on matched probes (harmonicTwoTone ×7, spectralSweep ×7), 24 two-control pairs.
Technical explanation. At default settings: output -22.9 dBFS RMS (crest 8.8 dB); stereo width 0.02, L/R correlation +1.00; spectral tilt -0.32 dB/octave; 98% of the impulse response's energy in its first 5 ms; decay T30 0.51 s, EDT 2.93 s; harmonics H2 -46 dB, H3 -9 dB re the linear response.
Structure:
- at full input: H2 -50 dB, H3 -35 dB, H4 -35 dB, H5 -22 dB, H6 -51 dB
- THD -24.0 dB at the quietest burst → -21.5 dB at the loudest; intermodulation -7.2 dB
Two-control pairs captured: AMP Type×Edge, Drive×AMP Type, Drive×Edge, Drive×LPF Cutoff, LPF Cutoff×AMP Type, LPF Cutoff×Edge (interaction analysis in the main notebook).
Caveats:
- some long settings decay more slowly than the recording allows; their T30 is a lower bound
- at least one setting mutes the output; those captures are excluded from spectral analysis
Plain explanation: The control to reach for first is Drive: THD at full input -104 → -21 dB. After that, LPF Cutoff and AMP Type make the next biggest differences. Output Level and DryWet set how much of the effect you hear and how loud it is. At default the tail takes about 0.5 s to die away. At default the output is close to mono.
In other words, the main points:
- 5 of 6 tested controls measurably change the sound.
- Biggest lever beyond mix and level: Drive, 27.6× the smallest change that matters (THD at full input -104 → -21 dB).
- At default: stereo width 0.02, decay T30 0.51 s, output -22.9 dBFS RMS.
- Main caveat: some long settings decay more slowly than the recording allows; their T30 is a lower bound.
- Still to measure: T1, T3, T4 (see
TESTS_NEEDED.md).
Show code
show_knobs('Amp Simulator')
Gap Fill: each control in physical units¶
Every control stepped on a probe matched to what it does (17 steps for time and rate controls, 9 for the rest), read as the physical quantity it sets: how far a delay tap moves, level or treble lost per repeat, LFO rate and pitch swing, gate length, THD, intermodulation, compressor ratio, knee, attack and release, and where a gate opens and closes. Times are read inside one capture (channel against channel) because Gap Fill runs fully wet and file starts wander by about ±50 ms.
Show code
show_gapfill('Amp Simulator')
How to read these charts. Each chart is one control. Left to right is the control's raw value as sent to the Motif (low to high setting); the height of the line is the physical quantity that control sets, measured from the recording. The title names the control, then the test signal used.
AMP-Type · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -7.75 at raw 0 to -13.8 at raw 3.
AMP-Type · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -10.3 at raw 0 to -10.1 at raw 3, peaking at -9.57, dipping to -11.3.
Drive · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -84.9 at raw 0 to -7.72 at raw 127.
Drive · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -86.4 at raw 0 to -10.2 at raw 127.
Edge · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -7.74 at raw 0 to -7.62 at raw 127, peaking at -6.9, dipping to -7.79.
Edge · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -10.6 at raw 0 to -10.2 at raw 127.
LPF-Cutoff · pinkPluck. Played: pink-noise bursts at three levels, then plucked notes. The line is Hz spectral centroid: the spectrum's centre of gravity, a measure of brightness; higher means brighter; here it goes from 382 at raw 0 to 4,142 at raw 60.
Comp + Dist¶
Show code
show_card('Comp + Dist')
Comp + Dist: what the measurements say¶
Recap. A distortion stage with 14 tested controls, 11 of which measurably change the sound. Beyond mix and level, the biggest lever is Low Gain: gain compression across the input range -55.7 → -18.2 dB. 2 do nothing with the others at default. Measured with 137 captures: 74 on the main sweep + tone probe (one control at a time), 31 on matched probes (harmonicTwoTone ×21, steppedTransients ×7, dynamicsStaircase ×3), 32 two-control pairs.
Technical explanation. At default settings: output -26.1 dBFS RMS (crest 8.1 dB); stereo width 0.02, L/R correlation +1.00; spectral tilt -0.89 dB/octave; 99% of the impulse response's energy in its first 5 ms; decay T30 1.99 s, EDT 8.91 s; harmonics H2 -49 dB, H3 -9 dB re the linear response.
Structure:
- at full input: H2 -55 dB, H3 -36 dB, H4 -42 dB, H5 -23 dB, H6 -65 dB
- THD -24.9 dB at the quietest burst → -22.6 dB at the loudest; intermodulation -7.3 dB
Two-control pairs captured: Attack×Release, Drive×Edge, Drive×Mid Gain, Drive×Ratio, Low Gain×Drive, Low Gain×Mid Gain, Low Gain×Ratio, Mid Gain×Ratio (interaction analysis in the main notebook).
Caveats:
- some long settings decay more slowly than the recording allows; their T30 is a lower bound
- Low Frequency, Mid Frequency did nothing because the matching gain sits at 0 dB in the one-at-a-time design
- at least one setting mutes the output; those captures are excluded from spectral analysis
Plain explanation: The control to reach for first is Low Gain: gain compression across the input range -55.7 → -18.2 dB. After that, Drive, Mid Gain and Ratio make the next biggest differences. Output Level and DryWet set how much of the effect you hear and how loud it is. Low Frequency and Mid Frequency made no measurable difference with the other controls at default. At default the tail takes about 2.0 s to die away. At default the output is close to mono.
In other words, the main points:
- 11 of 14 tested controls measurably change the sound; 2 do nothing with the others at default.
- Biggest lever beyond mix and level: Low Gain, 37.5× the smallest change that matters (gain compression across the input range -55.7 → -18.2 dB).
- At default: stereo width 0.02, decay T30 1.99 s, output -26.1 dBFS RMS.
- Main caveat: some long settings decay more slowly than the recording allows; their T30 is a lower bound.
- Still to measure: T1, T13, T3, T4 (see
TESTS_NEEDED.md).
Show code
show_knobs('Comp + Dist')
Gap Fill: each control in physical units¶
Every control stepped on a probe matched to what it does (17 steps for time and rate controls, 9 for the rest), read as the physical quantity it sets: how far a delay tap moves, level or treble lost per repeat, LFO rate and pitch swing, gate length, THD, intermodulation, compressor ratio, knee, attack and release, and where a gate opens and closes. Times are read inside one capture (channel against channel) because Gap Fill runs fully wet and file starts wander by about ±50 ms.
Show code
show_gapfill('Comp + Dist')
How to read these charts. Each chart is one control. Left to right is the control's raw value as sent to the Motif (low to high setting); the height of the line is the physical quantity that control sets, measured from the recording. The title names the control, then the test signal used.
Attack · dynamicsTiming. Played: a 440 Hz tone that jumps 30 dB louder and back. The line is ms attack: how long the compressor takes to clamp down after the tone jumps louder; here it barely moves (about 0 throughout).
Drive · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -81.2 at raw 0 to -7.37 at raw 127.
Drive · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -51.1 at raw 0 to -10.2 at raw 127.
Edge · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -7.37 at raw 0 to -6.75 at raw 127, dipping to -8.38.
Edge · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -11.3 at raw 0 to -10.3 at raw 127.
LPF-Cutoff · pinkPluck. Played: pink-noise bursts at three levels, then plucked notes. The line is Hz spectral centroid: the spectrum's centre of gravity, a measure of brightness; higher means brighter; here it goes from 384 at raw 0 to 3,014 at raw 60.
Ratio · bandStaircase. Played: tones stepped from −60 to −6 dBFS at 100 Hz, 1 kHz and 6 kHz. The line is ratio: the compression ratio above the knee: a ratio of 4 turns a 4 dB rise into a 1 dB rise; here it barely moves (about 100 throughout).
Release · dynamicsTiming. Played: a 440 Hz tone that jumps 30 dB louder and back. The line is ms release: how long the compressor takes to let go after the tone drops; here it goes from 23.1 at raw 0 to 909 at raw 15.
Threshold · bandStaircase. Played: tones stepped from −60 to −6 dBFS at 100 Hz, 1 kHz and 6 kHz. The line is dBFS knee at 1 kHz: the input level where compression starts; here it barely moves (about -55.5 throughout).
Dist + Delay¶
Show code
show_card('Dist + Delay')
Dist + Delay: what the measurements say¶
Recap. A distortion stage with 10 tested controls, 10 of which measurably change the sound. Beyond mix and level, the biggest lever is Dist Drive: THD at full input -77 → -21 dB. Measured with 100 captures: 51 on the main sweep + tone probe (one control at a time), 21 on matched probes (harmonicTwoTone ×21), 28 two-control pairs.
Technical explanation. At default settings: output -21.2 dBFS RMS (crest 8.5 dB); stereo width 0.11, L/R correlation +0.98; spectral tilt -0.27 dB/octave; 95% of the impulse response's energy in its first 5 ms; decay T30 0.65 s, EDT 2.69 s; harmonics H2 -40 dB, H3 -9 dB re the linear response.
Structure:
- at full input: H2 -50 dB, H3 -35 dB, H4 -35 dB, H5 -21 dB, H6 -52 dB
- THD -21.9 dB at the quietest burst → -20.5 dB at the loudest; intermodulation -7.3 dB
Two-control pairs captured: Delay Time L×Delay Feedback Time, Dist Drive×Delay Feedback Level, Dist Drive×Dist Low Gain, Dist Drive×Dist Mid Gain, Dist Low Gain×Delay Feedback Level, Dist Low Gain×Dist Mid Gain, Dist Mid Gain×Delay Feedback Level (interaction analysis in the main notebook).
Caveats:
- some long settings decay more slowly than the recording allows; their T30 is a lower bound
- at least one setting mutes the output; those captures are excluded from spectral analysis
Plain explanation: The control to reach for first is Dist Drive: THD at full input -77 → -21 dB. After that, Dist Low Gain, Dist Mid Gain and Delay Feedback Level make the next biggest differences. Dist Output Level and DryWet set how much of the effect you hear and how loud it is. At default the tail takes about 0.6 s to die away. At default it has a moderate stereo spread.
In other words, the main points:
- 10 of 10 tested controls measurably change the sound.
- Biggest lever beyond mix and level: Dist Drive, 18.9× the smallest change that matters (THD at full input -77 → -21 dB).
- At default: stereo width 0.11, decay T30 0.65 s, output -21.2 dBFS RMS.
- Main caveat: some long settings decay more slowly than the recording allows; their T30 is a lower bound.
- Still to measure: T1, T4 (see
TESTS_NEEDED.md).
Show code
show_knobs('Dist + Delay')
Gap Fill: each control in physical units¶
Every control stepped on a probe matched to what it does (17 steps for time and rate controls, 9 for the rest), read as the physical quantity it sets: how far a delay tap moves, level or treble lost per repeat, LFO rate and pitch swing, gate length, THD, intermodulation, compressor ratio, knee, attack and release, and where a gate opens and closes. Times are read inside one capture (channel against channel) because Gap Fill runs fully wet and file starts wander by about ±50 ms.
Show code
show_gapfill('Dist + Delay')
How to read these charts. Each chart is one control. Left to right is the control's raw value as sent to the Motif (low to high setting); the height of the line is the physical quantity that control sets, measured from the recording. The title names the control, then the test signal used.
Delay-Feedback-Level · sweepTail. Played: a sweep followed by silence. The line is dB per repeat: how much quieter each repeat is than the one before; closer to 0 means more repeats; here it goes from -0.0379 at raw 0 to -0.0363 at raw 127, dipping to -16.9.
Delay-Feedback-Time · sweepTail. Played: a sweep followed by silence. The line is dB per repeat: how much quieter each repeat is than the one before; closer to 0 means more repeats; here it goes from -16.9 at raw 0 to -16.7 at raw 16383, peaking at -1.35.
Delay-Time-L · sweepTail. Played: a sweep followed by silence. The line is ms the tap moves: how far the echo moves in time against the other channel; here it goes from 0 at raw 0 to 0.0907 at raw 16383, peaking at 0.113.
Delay-Time-R · sweepTail. Played: a sweep followed by silence. The line is ms the tap moves: how far the echo moves in time against the other channel; here it goes from 0 at raw 0 to -0.0454 at raw 16383, peaking at 0.0454, dipping to -0.0907.
Dist-Drive · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -79.7 at raw 0 to -7.9 at raw 127.
Dist-Drive · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -60 at raw 0 to -10.2 at raw 127.
Distortion¶
Show code
show_card('Distortion')
Distortion: what the measurements say¶
Recap. A distortion stage with 10 tested controls, 7 of which measurably change the sound. Beyond mix and level, the biggest lever is Drive: THD at full input -103 → -21 dB. 1 does nothing with the others at default. Measured with 100 captures: 51 on the main sweep + tone probe (one control at a time), 21 on matched probes (harmonicTwoTone ×21), 28 two-control pairs.
Technical explanation. At default settings: output -22.9 dBFS RMS (crest 8.4 dB); stereo width 0.02, L/R correlation +1.00; spectral tilt -0.88 dB/octave; 99% of the impulse response's energy in its first 5 ms; decay T30 0.50 s, EDT 2.83 s; harmonics H2 -46 dB, H3 -9 dB re the linear response.
Structure:
- at full input: H2 -51 dB, H3 -36 dB, H4 -35 dB, H5 -22 dB, H6 -52 dB
- THD -24.1 dB at the quietest burst → -21.5 dB at the loudest; intermodulation -7.2 dB
Two-control pairs captured: Drive×Edge, Drive×LPF Cutoff, Drive×Low Gain, Drive×Mid Gain, Low Gain×LPF Cutoff, Mid Gain×LPF Cutoff, Mid Gain×Low Gain (interaction analysis in the main notebook).
Caveats:
- Mid Frequency did nothing because the matching gain sits at 0 dB in the one-at-a-time design
- at least one setting mutes the output; those captures are excluded from spectral analysis
Plain explanation: The control to reach for first is Drive: THD at full input -103 → -21 dB. After that, Mid Gain, Low Gain and LPF Cutoff make the next biggest differences. Output Level and DryWet set how much of the effect you hear and how loud it is. Mid Frequency made no measurable difference with the other controls at default. At default the tail takes about 0.5 s to die away. At default the output is close to mono.
In other words, the main points:
- 7 of 10 tested controls measurably change the sound; 1 does nothing with the others at default.
- Biggest lever beyond mix and level: Drive, 27.2× the smallest change that matters (THD at full input -103 → -21 dB).
- At default: stereo width 0.02, decay T30 0.50 s, output -22.9 dBFS RMS.
- Main caveat: Mid Frequency did nothing because the matching gain sits at 0 dB in the one-at-a-time design.
- Still to measure: T1, T13, T3 (see
TESTS_NEEDED.md).
Show code
show_knobs('Distortion')
Gap Fill: each control in physical units¶
Every control stepped on a probe matched to what it does (17 steps for time and rate controls, 9 for the rest), read as the physical quantity it sets: how far a delay tap moves, level or treble lost per repeat, LFO rate and pitch swing, gate length, THD, intermodulation, compressor ratio, knee, attack and release, and where a gate opens and closes. Times are read inside one capture (channel against channel) because Gap Fill runs fully wet and file starts wander by about ±50 ms.
Show code
show_gapfill('Distortion')
How to read these charts. Each chart is one control. Left to right is the control's raw value as sent to the Motif (low to high setting); the height of the line is the physical quantity that control sets, measured from the recording. The title names the control, then the test signal used.
Drive · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -86 at raw 0 to -6.96 at raw 127.
Drive · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -86.1 at raw 0 to -10.2 at raw 127.
Edge · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -8.01 at raw 0 to -7.89 at raw 127, peaking at -6.78.
Edge · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -10.6 at raw 0 to -10.2 at raw 127.
LPF-Cutoff · pinkPluck. Played: pink-noise bursts at three levels, then plucked notes. The line is Hz spectral centroid: the spectrum's centre of gravity, a measure of brightness; higher means brighter; here it goes from 388 at raw 0 to 3,319 at raw 60.
Odrv + Delay¶
Show code
show_card('Odrv + Delay')
Odrv + Delay: what the measurements say¶
Recap. A distortion stage with 10 tested controls, 10 of which measurably change the sound. Beyond mix and level, the biggest lever is Dist Drive: THD at full input -77 → -21 dB. Measured with 101 captures: 51 on the main sweep + tone probe (one control at a time), 22 on matched probes (impulseTail ×13, harmonicTwoTone ×9), 28 two-control pairs.
Technical explanation. At default settings: output -21.7 dBFS RMS (crest 8.3 dB); stereo width 0.10, L/R correlation +0.98; spectral tilt -0.97 dB/octave; 99% of the impulse response's energy in its first 5 ms; decay T30 0.64 s, EDT 2.68 s; harmonics H2 -45 dB, H3 -9 dB re the linear response.
Structure:
- at full input: H2 -50 dB, H3 -35 dB, H4 -36 dB, H5 -21 dB, H6 -53 dB
- THD -22.2 dB at the quietest burst → -20.6 dB at the loudest; intermodulation -7.3 dB
Two-control pairs captured: Delay Time L×Delay Feedback Time, Delay Time L×Delay Mix, Delay Time R×Delay Mix, Delay Time R×Delay Time L, Dist Drive×Delay Mix, Dist Drive×Delay Time L, Dist Drive×Delay Time R (interaction analysis in the main notebook).
Caveats:
- some long settings decay more slowly than the recording allows; their T30 is a lower bound
- at least one setting mutes the output; those captures are excluded from spectral analysis
Plain explanation: The control to reach for first is Dist Drive: THD at full input -77 → -21 dB. After that, Delay Time R, Delay Time L and Delay Mix make the next biggest differences. Dist Output Level and DryWet set how much of the effect you hear and how loud it is. At default the tail takes about 0.6 s to die away. At default it has a moderate stereo spread.
In other words, the main points:
- 10 of 10 tested controls measurably change the sound.
- Biggest lever beyond mix and level: Dist Drive, 18.9× the smallest change that matters (THD at full input -77 → -21 dB).
- At default: stereo width 0.10, decay T30 0.64 s, output -21.7 dBFS RMS.
- Main caveat: some long settings decay more slowly than the recording allows; their T30 is a lower bound.
- Still to measure: T1, T4 (see
TESTS_NEEDED.md).
Show code
show_knobs('Odrv + Delay')
Gap Fill: each control in physical units¶
Every control stepped on a probe matched to what it does (17 steps for time and rate controls, 9 for the rest), read as the physical quantity it sets: how far a delay tap moves, level or treble lost per repeat, LFO rate and pitch swing, gate length, THD, intermodulation, compressor ratio, knee, attack and release, and where a gate opens and closes. Times are read inside one capture (channel against channel) because Gap Fill runs fully wet and file starts wander by about ±50 ms.
Show code
show_gapfill('Odrv + Delay')
How to read these charts. Each chart is one control. Left to right is the control's raw value as sent to the Motif (low to high setting); the height of the line is the physical quantity that control sets, measured from the recording. The title names the control, then the test signal used.
Delay-Feedback-Level · sweepTail. Played: a sweep followed by silence. The line is dB per repeat: how much quieter each repeat is than the one before; closer to 0 means more repeats; here it goes from -0.0724 at raw 0 to -0.074 at raw 127, dipping to -15.9.
Delay-Feedback-Time · sweepTail. Played: a sweep followed by silence. The line is dB per repeat: how much quieter each repeat is than the one before; closer to 0 means more repeats; here it goes from -2.55 at raw 0 to -16.9 at raw 16383.
Delay-Time-L · sweepTail. Played: a sweep followed by silence. The line is ms the tap moves: how far the echo moves in time against the other channel; here it goes from 0 at raw 0 to 0.068 at raw 16383, peaking at 0.0907, dipping to -0.0454.
Delay-Time-R · sweepTail. Played: a sweep followed by silence. The line is ms the tap moves: how far the echo moves in time against the other channel; here it goes from 0 at raw 0 to 0.0907 at raw 16383, peaking at 0.113, dipping to -0.068.
Dist-Drive · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -79.6 at raw 0 to -7.86 at raw 127.
Dist-Drive · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -59.9 at raw 0 to -10.2 at raw 127.
Overdrive¶
Show code
show_card('Overdrive')
Overdrive: what the measurements say¶
Recap. A distortion stage with 10 tested controls, 7 of which measurably change the sound. Beyond mix and level, the biggest lever is Drive: THD at full input -103 → -21 dB. 2 do nothing with the others at default. Measured with 100 captures: 51 on the main sweep + tone probe (one control at a time), 21 on matched probes (harmonicTwoTone ×21), 28 two-control pairs.
Technical explanation. At default settings: output -23.1 dBFS RMS (crest 8.1 dB); stereo width 0.02, L/R correlation +1.00; spectral tilt -0.96 dB/octave; 99% of the impulse response's energy in its first 5 ms; decay T30 0.51 s, EDT 2.87 s; harmonics H2 -47 dB, H3 -9 dB re the linear response.
Structure:
- at full input: H2 -51 dB, H3 -36 dB, H4 -35 dB, H5 -22 dB, H6 -53 dB
- THD -24.2 dB at the quietest burst → -21.5 dB at the loudest; intermodulation -7.2 dB
Two-control pairs captured: Drive×Edge, Drive×LPF Cutoff, Drive×Low Gain, Drive×Mid Gain, Low Gain×LPF Cutoff, Mid Gain×LPF Cutoff, Mid Gain×Low Gain (interaction analysis in the main notebook).
Caveats:
- some long settings decay more slowly than the recording allows; their T30 is a lower bound
- Low Frequency, Mid Width did nothing because the matching gain sits at 0 dB in the one-at-a-time design
- at least one setting mutes the output; those captures are excluded from spectral analysis
Plain explanation: The control to reach for first is Drive: THD at full input -103 → -21 dB. After that, Mid Gain, Low Gain and LPF Cutoff make the next biggest differences. Output Level and DryWet set how much of the effect you hear and how loud it is. Low Frequency and Mid Width made no measurable difference with the other controls at default. At default the tail takes about 0.5 s to die away. At default the output is close to mono.
In other words, the main points:
- 7 of 10 tested controls measurably change the sound; 2 do nothing with the others at default.
- Biggest lever beyond mix and level: Drive, 27.2× the smallest change that matters (THD at full input -103 → -21 dB).
- At default: stereo width 0.02, decay T30 0.51 s, output -23.1 dBFS RMS.
- Main caveat: some long settings decay more slowly than the recording allows; their T30 is a lower bound.
- Still to measure: T1, T13, T3, T4 (see
TESTS_NEEDED.md).
Show code
show_knobs('Overdrive')
Gap Fill: each control in physical units¶
Every control stepped on a probe matched to what it does (17 steps for time and rate controls, 9 for the rest), read as the physical quantity it sets: how far a delay tap moves, level or treble lost per repeat, LFO rate and pitch swing, gate length, THD, intermodulation, compressor ratio, knee, attack and release, and where a gate opens and closes. Times are read inside one capture (channel against channel) because Gap Fill runs fully wet and file starts wander by about ±50 ms.
Show code
show_gapfill('Overdrive')
How to read these charts. Each chart is one control. Left to right is the control's raw value as sent to the Motif (low to high setting); the height of the line is the physical quantity that control sets, measured from the recording. The title names the control, then the test signal used.
Drive · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -84.8 at raw 0 to -7.67 at raw 127.
Drive · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -86 at raw 0 to -10.2 at raw 127.
Edge · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -7.87 at raw 0 to -8.11 at raw 127, peaking at -6.67.
Edge · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -10.6 at raw 0 to -10.2 at raw 127.
LPF-Cutoff · pinkPluck. Played: pink-noise bursts at three levels, then plucked notes. The line is Hz spectral centroid: the spectrum's centre of gravity, a measure of brightness; higher means brighter; here it goes from 407 at raw 0 to 2,125 at raw 60.
V-Distortion¶
Show code
show_card('V-Distortion')
V-Distortion: what the measurements say¶
Recap. A distortion stage with 12 tested controls, 10 of which measurably change the sound. Beyond mix and level, the biggest lever is Over Drive: gain compression across the input range 0.0 → -18.2 dB. 2 do nothing with the others at default. Measured with 115 captures: 62 on the main sweep + tone probe (one control at a time), 25 on matched probes (harmonicTwoTone ×25), 28 two-control pairs.
Technical explanation. At default settings: output -12.6 dBFS RMS (crest 9.3 dB); stereo width 0.33, L/R correlation +0.80; spectral tilt -0.06 dB/octave; 83% of the impulse response's energy in its first 5 ms; harmonics H2 -34 dB, H3 -10 dB re the linear response.
Structure:
- at full input: H2 -68 dB, H3 -20 dB, H4 -49 dB, H5 -30 dB, H6 -47 dB
- THD -26.5 dB at the quietest burst → -19.5 dB at the loudest; intermodulation -6.8 dB
Two-control pairs captured: Delay Time L×Feedback Time, Device×Presence, Over Drive×Device, Over Drive×Presence, Over Drive×Speaker Type, Speaker Type×Device, Speaker Type×Presence (interaction analysis in the main notebook).
Caveats:
- some long settings decay more slowly than the recording allows; their T30 is a lower bound
- at least one setting mutes the output; those captures are excluded from spectral analysis
Plain explanation: The control to reach for first is Over Drive: gain compression across the input range 0.0 → -18.2 dB. After that, Speaker Type, Device and Presence make the next biggest differences. DryWet and Output Level set how much of the effect you hear and how loud it is. Feedback Hi Damp and Feedback Time made no measurable difference with the other controls at default. At default it has a moderate stereo spread.
In other words, the main points:
- 10 of 12 tested controls measurably change the sound; 2 do nothing with the others at default.
- Biggest lever beyond mix and level: Over Drive, 18.2× the smallest change that matters (gain compression across the input range 0.0 → -18.2 dB).
- At default: stereo width 0.33, output -12.6 dBFS RMS.
- Main caveat: some long settings decay more slowly than the recording allows; their T30 is a lower bound.
- Still to measure: T1, T4 (see
TESTS_NEEDED.md).
Show code
show_knobs('V-Distortion')
Gap Fill: each control in physical units¶
Every control stepped on a probe matched to what it does (17 steps for time and rate controls, 9 for the rest), read as the physical quantity it sets: how far a delay tap moves, level or treble lost per repeat, LFO rate and pitch swing, gate length, THD, intermodulation, compressor ratio, knee, attack and release, and where a gate opens and closes. Times are read inside one capture (channel against channel) because Gap Fill runs fully wet and file starts wander by about ±50 ms.
Show code
show_gapfill('V-Distortion')
How to read these charts. Each chart is one control. Left to right is the control's raw value as sent to the Motif (low to high setting); the height of the line is the physical quantity that control sets, measured from the recording. The title names the control, then the test signal used.
Delay-Time-L · sweepTail. Played: a sweep followed by silence. The line is ms the tap moves: how far the echo moves in time against the other channel; here it goes from 0 at raw 0 to 0 at raw 16383, dipping to -457.
Delay-Time-R · sweepTail. Played: a sweep followed by silence. The line is ms the tap moves: how far the echo moves in time against the other channel; here it goes from 0 at raw 0 to 0 at raw 16383, dipping to -427.
Device · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -8.37 at raw 0 to -10.7 at raw 4, dipping to -12.1.
Device · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -11.3 at raw 0 to 2.38 at raw 4, dipping to -15.8.
Feedback-Hi-Damp · pinkPluck. Played: pink-noise bursts at three levels, then plucked notes. The line is Hz spectral centroid: the spectrum's centre of gravity, a measure of brightness; higher means brighter; here it barely moves (about 4,221 throughout).
Feedback-Level · sweepTail. Played: a sweep followed by silence. The line is dB per repeat: how much quieter each repeat is than the one before; closer to 0 means more repeats; here it goes from -0.597 at raw 0 to -0.484 at raw 127, peaking at 2.95, dipping to -5.13.
Feedback-Time · sweepTail. Played: a sweep followed by silence. The line is dB per repeat: how much quieter each repeat is than the one before; closer to 0 means more repeats; here it goes from 2.57 at raw 0 to 5.11 at raw 16383, peaking at 5.66, dipping to -2.56.
Over-Drive · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -80.7 at raw 0 to -8.42 at raw 100.
Over-Drive · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -48.7 at raw 0 to -9.8 at raw 100.
Presence · pinkPluck. Played: pink-noise bursts at three levels, then plucked notes. The line is Hz spectral centroid: the spectrum's centre of gravity, a measure of brightness; higher means brighter; here it goes from 1,707 at raw 0 to 7,040 at raw 20.
Speaker-Type · transferSine. Played: a 100 Hz sine at −6 dBFS. The line is dB THD: total harmonic distortion: how loud the added overtones are against the note itself. −40 dB is clean, 0 dB would be overtones as loud as the note; higher on the chart means more distortion; here it goes from -8.37 at raw 0 to 29.8 at raw 5.
Speaker-Type · twoToneLadder. Played: two notes together (220 and 697 Hz), stepped from very quiet to loud. The line is dB intermodulation: how loud the extra tones created between two notes are against the notes themselves, which is what makes chords sound harsh; higher means harsher; here it goes from -11.3 at raw 0 to -8.83 at raw 5, dipping to -14.
Revision 36 · 2026-10-15
Revision history
- Rev 36 · 2026-10-15: The Distortion drive ladders are re-recorded in the current setup (80 takes) and replace those of 2026-09-28, whose flat-topped waves came from the levels of the setup at the time, not from the effects: with the drive up, each distortion gives a square wave whose tops sag, and its Output Level only scales it.
- Rev 35 · 2026-10-12: The main page folds by topic and each family's detail page folds by effect: every section is closed until opened, with one control to open or close them all.
- Rev 34 · 2026-10-12: Every sheet: a play button steps through each control's settings; every recorded pair of controls drawn, with whether they simply add or one changes the other; EQ frequency and width controls drawn with their band at full boost. New detailed charts on every board: which controls depend on each other; the EQ bands moving; the ring modulator's pitch against its controls.
- Rev 33 · 2026-10-12: Every control on every effect's sheet: all its tested settings overlaid in one cell, and its measured law in physical units where a probe reads one. Misc board: the equalisers' bands at full cut and boost.
- Rev 32 · 2026-10-12: Headline findings set apart with larger titles; a note under the three whose graphic shows less than the headline says (Lo-Fi rate, delay feedback, repeats).
- Rev 31 · 2026-10-12: Main page: a graphic under each of the eight headline findings (the delay feedback one animated), each with a plain-terms line.
- Rev 30 · 2026-10-12: Main page opens with a chart of where every capture went and the central technique in pictures: the sweep, and the spikes the matched filter turns a recording of it into.
- Rev 29 · 2026-10-12: Misc board: the ring modulator's carrier pitch against OSC Freq Coarse and Fine, read from the sine takes.
- Rev 28 · 2026-10-11: Fifth capture batch in: the Reverb board gains the gap before the reverb starts against Initial Delay, the Chorus and Flanger boards gain the delay length against the delay knob.
- Rev 27 · 2026-10-11: Waves: a third page, what the instrument and effect waves measure: the note each one plays, where it starts repeating and how long the loop is, how long it rings, and the harmonics of each pitched wave.
- Rev 26 · 2026-10-11: Waves: the instrument and effect tiles now show the opening of the note (its first 8 cycles) instead of the whole take, so the individual waves can be seen.
- Rev 25 · 2026-10-11: Waves: a second page for the 955 instrument and effect waves, each drawn as the whole take of one note with one cycle of the sound under it where the wave holds a steady pitch.
- Rev 24 · 2026-10-08: Reverb knob pairs recorded (288 takes over the 12 distinct reverbs), so the reverb consoles' rings follow each other too; 799 knob pairs measured in all.
- Rev 23 · 2026-10-08: Every family page now opens with a comparison board (one row per effect, shared scales down each column) and control sheets with all tested settings side by side; each family's detailed charts are folded in beneath and the earlier pages are kept as detail pages.
- Rev 22 · 2026-10-08: Knob consoles: 2,120 new recordings of knob pairs, so within each effect's four strongest controls every knob's ring now follows every other (679 pairs measured, up from 155). A Waves page shows the 904 drum and percussion waves.
- Rev 21 · 2026-10-07: Delay page rebuilt the same way: every delay's echoes side by side, and each control's tested settings next to each other as echo patterns.
- Rev 20 · 2026-10-07: Reverb page rebuilt for comparison: one board with every distinct reverb as a row and every measure as a column on a shared scale, then each reverb's controls with all tested settings side by side. The detailed charts are folded in beneath; the earlier page is kept as the detail page. Knob consoles now use a slider for the selected knob, and controls with nothing measurable are listed, not drawn.
- Rev 19 · 2026-10-07: A knob console on every effect: each ring shows where along the knob's travel the sound changes, and turning a knob shows how the knobs captured together with it respond.
- Rev 18 · 2026-10-07: Reverb taken apart in time: how fast separate reflections merge into a wash; the tail's colour through time; how alike left and right are at each pitch and through the decay; how smooth each tail is against noise of the same tone; the Reverb Time control against Yamaha's table; and the twenty reverb names compared pair by pair.
- Rev 17 · 2026-10-07: Charts that only compared output level or gain are removed from every page except the compressors and gates, where level is what the effect does.
- Rev 16 · 2026-10-07: Capture set finished and audited (14,635 takes; the takes recorded through a reverb are all replaced). Corrections: Celeste 1's control shown as Delay is its Feedback Level, and Symphonic's shown as Feedback is its Delay Offset; two Symphonic controls that do not exist on the effect are removed. New charts in time and wave shape rather than level: Delay, where every echo lands as each time control is turned; Distortion, the wave that comes out as the drive rises; Lo-Fi, the output wave sample by sample at each Sampling Freq setting; Chorus and Flanger, the delay line followed as it sweeps; Phaser and Wah, where each notch or peak sits in Hz from moment to moment; Reverb, the separate early reflections in the first quarter second after one click; Modulation and Tech, each side turned up and down from moment to moment.
- Rev 15 · 2026-10-06: Pitch Change: a click train in, and when each click comes out.
- Rev 14 · 2026-10-06: Distortion: output and distortion against input level on a smooth ramp, harmonics against the pitch of the note, high-note harmonics folding back off 44.1 kHz (no oversampling), a bass note modulating a treble note, input-against-output loops, and the amp and cabinet filters' level and phase.
- Rev 13 · 2026-10-06: Lo-Fi on a smoothly rising tone: Word Length sets a clipping ceiling and adds no quantisation noise; the five Lo-Fi effects compared on the same ramp.
- Rev 12 · 2026-10-06: Lo-Fi: a rising note against everything that comes out with it, at each sampling-rate setting. Pitch Change: the cluster of lines a shifted note returns as, and the splice window read from it (about 35 ms and 28 ms).
- Rev 11 · 2026-10-06: The same routing fault is confirmed for the 1,835 re-takes of 2026-09-30/10-01 (the dry-plus-wet timing takes and the full-rate Lo-Fi takes). No published chart used them; they are withdrawn from the counts and are being re-recorded.
- Rev 10 · 2026-10-06: Correction: the all-effects comparison (section 17 of the main report), added earlier today, is withdrawn. Its 625 recordings were made with the Motif's System Reverb left in the signal path and are being re-recorded. New: compressor timing inside the distortion chains, wah filter sweeps, reverb decay per octave band.
- Rev 9 · 2026-10-06: Follow-up captures analysed: compressor attack and release against step size, MultiBand Comp 2 band by band, Noise Gate opening, hold and closing times, and distortion on level steps (no sag: the clippers act instant by instant). Release times now require the level to stay recovered for 50 ms, which fixes readings fooled by ringing or by a delay's echo. Capture counts include the overnight batches.
- Rev 8 · 2026-10-05: Beyond level curves: gain-reduction speed, release shape, phase-space orbits, harmonic matrices, intermodulation maps, parallel coordinates, a behaviour map and loudness in phon and sone on the Dynamic atlas; harmonic-against-drive matrices (Distortion), stereo LFO orbits (Chorus, Flanger, Phaser, Modulation), an echo map (Delay) and a decay-rate matrix (Reverb).
- Rev 7 · 2026-10-04: All figures vector and stacked one per row; control tables replaced by interactive charts; every section in four parts (recap, professional, plain, main points); capture counts include Gap Fill; six more Gap Fill probes analysed (dynamics timing, band staircase, gate ramp, two-tone ladder, tone triplet, pink pluck).
- Rev 6 · 2026-10-04: Complete 13-category analysis with detail ladders; all notebooks rebuilt with executed cells and interactive charts.
- Rev 5 · 2026-10-01: T28/T29 re-take analysis (dry/wet time references, Lo-Fi full-rate captures); Reverb detail ladders.
- Rev 4 · 2026-09-30: Reverb analysis from full 9,876 Gap Fill run; two-voice explanations added to main page sections 1–15.
- Rev 3 · 2026-09-29: Gap Fill captures: delay and feedback time laws, LFO maps, drive transfer curves, Lo-Fi rate, early reflections; Gate/Reverse Gate relabelled; interactive charts, atlas links, dark theme.
- Rev 2 · 2026-09-28: Gate Reverb time origin fixed; Auto Pan phase and Distortion harmonics computed from data.
- Rev 1 · 2026-09-27: First complete report: main analysis and 13 atlas notebooks.