Flanger — effect atlas¶
9 effects · 1,114 captures. Short modulated delays with feedback, producing a moving comb filter. As with chorus, the comb moves while it is measured; LFO rate, depth and the left/right LFO phase come from the sustained chord.
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 = {'Dynamic Flanger': (8, 6), 'Flanger 1': (9, 0), 'Flanger 2': (10, 0), 'Flanger 3': (13, 0), 'Tempo Flanger': (9, 1), 'V-Flanger': (15, 0), 'Vintage Flanger 1': (11, 0), 'Vintage Flanger 2': (11, 0), 'Vintage Flanger 3': (11, 0)}
show(cards.family_overview(df, 'Flanger', knob_counts, curves))
Show code
iviz.family_fig(df, curves, 'Flanger').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.
Less reliable in detail (repeat captures differ by over 3 dB, usually a running LFO): Flanger 1, Flanger 2, Flanger 3, Tempo Flanger, V-Flanger, Vintage Flanger 1, Vintage Flanger 2, Vintage Flanger 3. These effects move while they are measured, so each curve is one snapshot of a response that sweeps back and forth; read the overall tilt, not individual notches. The LFO maps in the cards and in §14 of the main analysis show the movement itself. Not shown: level (each curve is centred on its own median), anything that changes over time.
Plain explanation: this is the effect's tone — which parts of the sound it makes louder or quieter. V-Flanger, Vintage Flanger 1, Vintage Flanger 2 and Vintage Flanger 3 roll off the top end early, so they sound darker. Because these effects sweep constantly, think of each line as a single frame of a moving picture.
In other words, the main points:
- Most shaping: V-Flanger, 33 dB from peak to deepest cut.
- Darkest (top end rolled off early): V-Flanger, Vintage Flanger 1, Vintage Flanger 2, Vintage Flanger 3.
- Least repeatable in detail (usually a running LFO): Flanger 1, Flanger 2, Flanger 3, Tempo Flanger, V-Flanger, Vintage Flanger 1, Vintage Flanger 2, Vintage Flanger 3.
Show code
iviz.tone_bands(df, curves, 'Flanger')
The stereo LFO as an orbit¶
A chorus, flanger or phaser is defined as much by how its left and right channels move against each other as by its rate and depth. This chart draws that relationship directly.
Show code
import kinetics, kviz, wviz, rviz
show_parts(wviz.sweep_parts(g, 'Flanger') + kviz.orbit_parts(df, curves, 'Flanger'))
What it shows. A click every 40 ms through each effect at its default settings with the dry sound mixed in. For every click, the time between the click and its echo is the length of the effect's delay line at that moment.
How to read it. Time runs left to right; height is how long the delay is. The shape of the line is the shape of the effect's modulator: straight ramps up and down are a triangle wave, a rounded line is a sine. Cyan is the left side, amber the right; where the two lines mirror each other, the two sides are sweeping in opposite directions, which is what makes the sound wide. Use the slider to change effect.
What it found.
- Flanger 1: 6.5 to 15.1 ms, 2.69 times a second, moving 47 ms per second in mid-sweep; left and right are together.
- Flanger 2: 6.4 to 15.2 ms, 2.69 times a second, moving 47 ms per second in mid-sweep; left and right are together.
- Flanger 3: 6.4 to 15.2 ms, 2.69 times a second, moving 47 ms per second in mid-sweep; left and right are together.
- Tempo Flanger: 6.4 to 15.2 ms, 2.65 times a second, moving 46 ms per second in mid-sweep; left and right are together.
- Vintage Flanger 1: 1.3 to 7.5 ms, 0.78 times a second, moving 9 ms per second in mid-sweep; left and right are together.
- Vintage Flanger 2: 1.3 to 7.5 ms, 0.78 times a second, moving 9 ms per second in mid-sweep; left and right are together.
- Vintage Flanger 3: 1.3 to 7.5 ms, 0.78 times a second, moving 9 ms per second in mid-sweep; left and right are together.
- Not drawn: Dynamic Flanger, V-Flanger.
- They have more than one moving voice (or none), and the strongest echo hops between voices, so a single line cannot be followed.
What it shows. The pitch of the left channel plotted against the pitch of the right, traced over ten seconds of a held chord (a different note in each channel, so each can be followed separately) at default settings. Time is not an axis: the LFO draws the same figure once per cycle.
How to read it. A line along the rising diagonal means both channels go sharp and flat together (one LFO for both). A line along the falling diagonal means they move in opposite directions. A loop that encloses area means one channel leads the other; a circle or square is a quarter cycle apart, which is what makes a chorus seem to rotate. Corners mean a triangle-wave LFO, rounded figures a sine. Use the slider to step through the effects.
What it found.
- Left and right move together: Flanger 1 (−0°), Flanger 2 (−0°), Flanger 3 (−0°), Vintage Flanger 1 (−3°), Vintage Flanger 2 (−3°), Vintage Flanger 3 (−3°).
- Left and right move without a fixed relation: V Flanger (+3°).
- The angle is the lead of the left channel over the right, averaged over the recording.
- The tracker follows one partial in a ±100 cent band, so swings beyond about ±60 cents are flattened and multi-voice effects, whose voices beat against each other, draw a tangle rather than a clean figure.
Dynamic Flanger¶
Show code
show_card('Dynamic Flanger')
Dynamic Flanger: what the measurements say¶
Recap. A modulation effect with 14 tested controls, 8 of which measurably change the sound. Beyond mix and level, the biggest lever is Feedback: LFO rate 30.20 → 1.24 Hz. 6 do nothing with the others at default. Measured with 133 captures: 68 on the main sweep + tone probe (one control at a time), 29 on matched probes (steppedTransients ×29), 36 two-control pairs.
Technical explanation. At default settings: output -30.6 dBFS RMS (crest 10.2 dB); stereo width 0.34, L/R correlation +0.77; spectral tilt -0.21 dB/octave; 100% of the impulse response's energy in its first 5 ms; harmonics H2 -75 dB, H3 -52 dB re the linear response.
Two-control pairs captured: Attack Time×Release Time, Delay Time Offset×Feedback, Feedback×High Gain, Feedback×Low Gain, Feedback×Sensitivity, High Gain×Low Gain, High Gain×Sensitivity, Low Gain×Sensitivity, Sensitivity×Dyna Threshold (interaction analysis in the main notebook).
Caveats:
- the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response
- High Frequency, Low Frequency did nothing because the matching gain sits at 0 dB in the one-at-a-time design
Plain explanation: The control to reach for first is Feedback: LFO rate 30.20 → 1.24 Hz. After that, High Gain, Low Gain and Sensitivity make the next biggest differences. DryWet sets how much of the effect you hear and how loud it is. Attack Time, Delay Time Offset, High Frequency, Low Frequency, Release Curve and Release 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:
- 8 of 14 tested controls measurably change the sound; 6 do nothing with the others at default.
- Biggest lever beyond mix and level: Feedback, 33.5× the smallest change that matters (LFO rate 30.20 → 1.24 Hz).
- At default: stereo width 0.34, output -30.6 dBFS RMS.
- Main caveat: the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response.
- Still to measure: T1, T13, T6, T7 (see
TESTS_NEEDED.md).
Show code
show_knobs('Dynamic Flanger')
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('Dynamic Flanger')
Flanger 1¶
Show code
show_card('Flanger 1')
Flanger 1: what the measurements say¶
Recap. A modulation effect with 13 tested controls, 9 of which measurably change the sound. Beyond mix and level, the biggest lever is LFO Depth: pitch wobble 0 → 290 cents. Measured with 131 captures: 66 on the main sweep + tone probe (one control at a time), 29 on matched probes (spectralSweep ×17, sustainedStereo ×7, impulseTail ×5), 36 two-control pairs.
Technical explanation. At default settings: output -28.6 dBFS RMS (crest 10.3 dB); stereo width 0.34, L/R correlation +0.77; spectral tilt +0.32 dB/octave; 39% of the impulse response's energy in its first 5 ms.
Structure:
- pitch LFO 2.68 Hz, 224 cents peak-to-peak, L/R phase +0°
- amplitude LFO — Hz, depth 0.00
- crosstalk L→R — dB, R→L — dB
Two-control pairs captured: Delay Offset×Feedback, Feedback×LFO Phase Diff, Feedback×Low Gain, LFO Depth×Feedback, LFO Depth×LFO Phase Diff, LFO Depth×Low Gain, LFO Phase Diff×Low Gain, LFO Speed×LFO Depth, Mid Width×LFO Depth (interaction analysis in the main notebook).
Caveats:
- the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response
Plain explanation: The control to reach for first is LFO Depth: pitch wobble 0 → 290 cents. After that, Feedback, LFO Phase Diff and Low Gain make the next biggest differences. DryWet sets how much of the effect you hear and how loud it is. At default it has a moderate stereo spread.
In other words, the main points:
- 9 of 13 tested controls measurably change the sound.
- Biggest lever beyond mix and level: LFO Depth, 58.0× the smallest change that matters (pitch wobble 0 → 290 cents).
- At default: stereo width 0.34, output -28.6 dBFS RMS.
- Main caveat: the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response.
- Still to measure: T1, T6, T7 (see
TESTS_NEEDED.md).
Show code
show_knobs('Flanger 1')
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('Flanger 1')
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.
LFO-Depth · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 0.00253 at raw 0 to 290 at raw 127.
LFO-Phase-Diff · sustainedStereo. Played: a held chord, one note per channel. The line is ° L/R LFO phase: how far the right channel's modulation runs ahead of or behind the left's; here it goes from 179 at raw 0 to -179 at raw 124.
LFO-Speed · longSine. Played: a steady 440 Hz sine. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.299 at raw 7 to 1.3 at raw 31.
LFO-Speed · sustainedStereo. Played: a held chord, one note per channel. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.282 at raw 7 to 8.08 at raw 95.
Flanger 2¶
Show code
show_card('Flanger 2')
Flanger 2: what the measurements say¶
Recap. A modulation effect with 13 tested controls, 10 of which measurably change the sound. Beyond mix and level, the biggest lever is LFO Depth: pitch wobble 0 → 290 cents. Measured with 131 captures: 66 on the main sweep + tone probe (one control at a time), 29 on matched probes (spectralSweep ×17, sustainedStereo ×7, impulseTail ×5), 36 two-control pairs.
Technical explanation. At default settings: output -28.4 dBFS RMS (crest 10.1 dB); stereo width 0.34, L/R correlation +0.77; spectral tilt +0.26 dB/octave; 43% of the impulse response's energy in its first 5 ms.
Structure:
- pitch LFO 2.68 Hz, 224 cents peak-to-peak, L/R phase +0°
- amplitude LFO — Hz, depth 0.00
- crosstalk L→R — dB, R→L — dB
Two-control pairs captured: Delay Offset×Feedback, Feedback×High Gain, LFO Depth×Feedback, LFO Depth×High Gain, LFO Depth×LFO Phase Diff, LFO Phase Diff×Feedback, LFO Phase Diff×High Gain, LFO Speed×LFO Depth, Mid Width×LFO Depth (interaction analysis in the main notebook).
Caveats:
- the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response
Plain explanation: The control to reach for first is LFO Depth: pitch wobble 0 → 290 cents. After that, LFO Phase Diff, Feedback and High Gain make the next biggest differences. DryWet sets how much of the effect you hear and how loud it is. At default it has a moderate stereo spread.
In other words, the main points:
- 10 of 13 tested controls measurably change the sound.
- Biggest lever beyond mix and level: LFO Depth, 58.0× the smallest change that matters (pitch wobble 0 → 290 cents).
- At default: stereo width 0.34, output -28.4 dBFS RMS.
- Main caveat: the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response.
- Still to measure: T1, T6, T7 (see
TESTS_NEEDED.md).
Show code
show_knobs('Flanger 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('Flanger 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.
LFO-Depth · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 0.00255 at raw 0 to 290 at raw 127.
LFO-Phase-Diff · sustainedStereo. Played: a held chord, one note per channel. The line is ° L/R LFO phase: how far the right channel's modulation runs ahead of or behind the left's; here it goes from -179 at raw 0 to -179 at raw 124, peaking at 134.
LFO-Speed · longSine. Played: a steady 440 Hz sine. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.299 at raw 7 to 1.3 at raw 31.
LFO-Speed · sustainedStereo. Played: a held chord, one note per channel. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.282 at raw 7 to 8.08 at raw 95.
Flanger 3¶
Show code
show_card('Flanger 3')
Flanger 3: what the measurements say¶
Recap. A modulation effect with 13 tested controls, 13 of which measurably change the sound. Beyond mix and level, the biggest lever is LFO Depth: pitch wobble 0 → 290 cents. Measured with 131 captures: 66 on the main sweep + tone probe (one control at a time), 29 on matched probes (spectralSweep ×17, sustainedStereo ×7, impulseTail ×5), 36 two-control pairs.
Technical explanation. At default settings: output -28.6 dBFS RMS (crest 10.3 dB); stereo width 0.34, L/R correlation +0.77; spectral tilt +0.27 dB/octave; 42% of the impulse response's energy in its first 5 ms.
Structure:
- pitch LFO 2.68 Hz, 224 cents peak-to-peak, L/R phase +0°
- amplitude LFO — Hz, depth 0.00
- crosstalk L→R — dB, R→L — dB
Two-control pairs captured: Delay Offset×Feedback, Feedback×Low Gain, LFO Depth×Feedback, LFO Depth×LFO Phase Diff, LFO Depth×Low Gain, LFO Phase Diff×Feedback, LFO Phase Diff×Low Gain, LFO Speed×LFO Depth, Mid Width×LFO Depth (interaction analysis in the main notebook).
Caveats:
- the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response
Plain explanation: The control to reach for first is LFO Depth: pitch wobble 0 → 290 cents. After that, LFO Phase Diff, Feedback and Low Gain make the next biggest differences. DryWet sets how much of the effect you hear and how loud it is. At default it has a moderate stereo spread.
In other words, the main points:
- 13 of 13 tested controls measurably change the sound.
- Biggest lever beyond mix and level: LFO Depth, 58.0× the smallest change that matters (pitch wobble 0 → 290 cents).
- At default: stereo width 0.34, output -28.6 dBFS RMS.
- Main caveat: the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response.
- Still to measure: T1, T6, T7 (see
TESTS_NEEDED.md).
Show code
show_knobs('Flanger 3')
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('Flanger 3')
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.
LFO-Depth · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 0.00248 at raw 0 to 290 at raw 127.
LFO-Phase-Diff · sustainedStereo. Played: a held chord, one note per channel. The line is ° L/R LFO phase: how far the right channel's modulation runs ahead of or behind the left's; here it goes from -179 at raw 0 to 179 at raw 124.
LFO-Speed · longSine. Played: a steady 440 Hz sine. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.299 at raw 7 to 1.3 at raw 31.
LFO-Speed · sustainedStereo. Played: a held chord, one note per channel. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.282 at raw 7 to 8.08 at raw 95.
Tempo Flanger¶
Show code
show_card('Tempo Flanger')
Tempo Flanger: what the measurements say¶
Recap. A modulation effect with 14 tested controls, 9 of which measurably change the sound. Beyond mix and level, the biggest lever is Feedback: lowers a band around 55 Hz by up to 16 dB (~0.1 octaves wide). 1 does nothing with the others at default. Measured with 130 captures: 69 on the main sweep + tone probe (one control at a time), 29 on matched probes (rhythmicGrid ×29), 32 two-control pairs.
Technical explanation. At default settings: output -28.6 dBFS RMS (crest 11.5 dB); stereo width 0.34, L/R correlation +0.77; spectral tilt -0.05 dB/octave; 41% of the impulse response's energy in its first 5 ms.
Two-control pairs captured: Delay×Feedback, Feedback×High Gain, Feedback×Low Gain, Feedback×Phase Diff, High Gain×Phase Diff, Low Gain×High Gain, Low Gain×Phase Diff, Mid Width×Depth (interaction analysis in the main notebook).
Caveats:
- the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response
Plain explanation: The control to reach for first is Feedback: lowers a band around 55 Hz by up to 16 dB (~0.1 octaves wide). After that, Low Gain, High Gain and Phase Diff make the next biggest differences. DryWet sets how much of the effect you hear and how loud it is. Re Trig made no measurable difference with the other controls at default. At default it has a moderate stereo spread.
In other words, the main points:
- 9 of 14 tested controls measurably change the sound; 1 does nothing with the others at default.
- Biggest lever beyond mix and level: Feedback, 14.6× the smallest change that matters (lowers a band around 55 Hz by up to 16 dB (~0.1 octaves wide)).
- At default: stereo width 0.34, output -28.6 dBFS RMS.
- Main caveat: the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response.
- Still to measure: T1, T6, T7 (see
TESTS_NEEDED.md).
Show code
show_knobs('Tempo Flanger')
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('Tempo Flanger')
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.
Depth · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 0.00256 at raw 0 to 288 at raw 127.
Phase-Diff · sustainedStereo. Played: a held chord, one note per channel. The line is ° L/R LFO phase: how far the right channel's modulation runs ahead of or behind the left's; here it goes from 180 at raw 0 to -179 at raw 124.
V-Flanger¶
Show code
show_card('V-Flanger')
V-Flanger: what the measurements say¶
Recap. A modulation effect with 16 tested controls, 15 of which measurably change the sound. Beyond mix and level, the biggest lever is Feedback: decay time 0.32 → 0.03 s. Measured with 146 captures: 79 on the main sweep + tone probe (one control at a time), 35 on matched probes (spectralSweep ×19, sustainedStereo ×9, impulseTail ×7), 32 two-control pairs.
Technical explanation. At default settings: output -32.0 dBFS RMS (crest 11.0 dB); stereo width 0.38, L/R correlation +0.72; spectral tilt -0.24 dB/octave; 9% of the impulse response's energy in its first 5 ms.
Structure:
- pitch LFO — Hz (faster than this probe can track — test T12), 50 cents peak-to-peak, L/R phase —°
- amplitude LFO 2.70 Hz, depth 0.04
- crosstalk L→R 10 dB, R→L -4 dB
Two-control pairs captured: Delay Offset×Feedback, Feedback×LFO Depth, Feedback×LFO Speed, Feedback×LFO Wave, LFO Speed×LFO Depth, LFO Wave×LFO Depth, LFO Wave×LFO Speed, Mid Width×LFO Depth (interaction analysis in the main notebook).
Caveats:
- the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response
- some long settings decay more slowly than the recording allows; their T30 is a lower bound
Plain explanation: The control to reach for first is Feedback: decay time 0.32 → 0.03 s. After that, LFO Wave, LFO Speed and LFO Depth make the next biggest differences. DryWet sets how much of the effect you hear and how loud it is. At default it has a moderate stereo spread.
In other words, the main points:
- 15 of 16 tested controls measurably change the sound.
- Biggest lever beyond mix and level: Feedback, 13.3× the smallest change that matters (decay time 0.32 → 0.03 s).
- At default: stereo width 0.38, output -32.0 dBFS RMS.
- Main caveat: the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response.
- Still to measure: T1, T12, T4, T6, T7 (see
TESTS_NEEDED.md).
Show code
show_knobs('V-Flanger')
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-Flanger')
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.
LFO-Depth · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 0.00736 at raw 0 to 39 at raw 127, peaking at 334.
LFO-Speed · longSine. Played: a steady 440 Hz sine. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.299 at raw 7 to 1.3 at raw 31.
LFO-Speed · sustainedStereo. Played: a held chord, one note per channel. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.283 at raw 7 to 3.31 at raw 127, peaking at 8.4.
LFO-Wave · longSine. Played: a steady 440 Hz sine. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 2.69 at raw 0 to 1.03 at raw 2.
Vintage Flanger 1¶
Show code
show_card('Vintage Flanger 1')
Vintage Flanger 1: what the measurements say¶
Recap. A modulation effect with 11 tested controls, 11 of which measurably change the sound. Beyond mix and level, the biggest lever is Speed: amplitude-LFO rate 0.28 → 10.00 Hz. Measured with 104 captures: 54 on the main sweep + tone probe (one control at a time), 26 on matched probes (spectralSweep ×15, sustainedStereo ×5, impulseTail ×3, stereoRouting ×3), 24 two-control pairs.
Technical explanation. At default settings: output -29.3 dBFS RMS (crest 18.2 dB); stereo width 0.63, L/R correlation +0.21; spectral tilt -0.48 dB/octave; 60% of the impulse response's energy in its first 5 ms; harmonics H2 -74 dB, H3 -48 dB re the linear response.
Structure:
- pitch LFO 0.78 Hz, 31 cents peak-to-peak, L/R phase +14°
- amplitude LFO 0.78 Hz, depth 0.27
- crosstalk L→R -39 dB, R→L -33 dB
Two-control pairs captured: Depth×Low Gain, Feedback×Depth, Feedback×Low Gain, Speed×Depth, Speed×Feedback, Speed×Low Gain (interaction analysis in the main notebook).
Caveats:
- the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response
Plain explanation: The control to reach for first is Speed: amplitude-LFO rate 0.28 → 10.00 Hz. After that, Feedback, Depth and Low Gain make the next biggest differences. At default left and right are largely independent, so it sounds wide.
In other words, the main points:
- 11 of 11 tested controls measurably change the sound.
- Biggest lever beyond mix and level: Speed, 37.6× the smallest change that matters (amplitude-LFO rate 0.28 → 10.00 Hz).
- At default: stereo width 0.63, output -29.3 dBFS RMS.
- Main caveat: the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response.
- Still to measure: T1, T6, T7 (see
TESTS_NEEDED.md).
Show code
show_knobs('Vintage Flanger 1')
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('Vintage Flanger 1')
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.
Depth · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 0.0102 at raw 0 to 43.1 at raw 127.
Speed · longSine. Played: a steady 440 Hz sine. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.117 at raw 29 to 0.221 at raw 58.
Speed · sustainedStereo. Played: a held chord, one note per channel. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.353 at raw 29 to 5.22 at raw 205.
Spread · stereoRouting. Played: bursts sent left only, right only, both in phase and both out of phase. The line is dB L/R isolation: how well left and right are kept apart; higher means less bleed; here it barely moves (about -64.4 throughout).
Type · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 32 at raw 0 to 36.5 at raw 2, peaking at 43.3.
Vintage Flanger 2¶
Show code
show_card('Vintage Flanger 2')
Vintage Flanger 2: what the measurements say¶
Recap. A modulation effect with 11 tested controls, 11 of which measurably change the sound. Beyond mix and level, the biggest lever is Speed: amplitude-LFO rate 0.28 → 10.02 Hz. Measured with 104 captures: 54 on the main sweep + tone probe (one control at a time), 26 on matched probes (spectralSweep ×15, sustainedStereo ×5, impulseTail ×3, stereoRouting ×3), 24 two-control pairs.
Technical explanation. At default settings: output -29.5 dBFS RMS (crest 18.5 dB); stereo width 0.64, L/R correlation +0.17; spectral tilt -0.77 dB/octave; 50% of the impulse response's energy in its first 5 ms.
Structure:
- pitch LFO 0.78 Hz, 31 cents peak-to-peak, L/R phase +13°
- amplitude LFO 0.78 Hz, depth 0.27
- crosstalk L→R -39 dB, R→L -33 dB
Two-control pairs captured: Depth×Low Gain, Feedback×Depth, Feedback×Low Gain, Speed×Depth, Speed×Feedback, Speed×Low Gain (interaction analysis in the main notebook).
Caveats:
- the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response
Plain explanation: The control to reach for first is Speed: amplitude-LFO rate 0.28 → 10.02 Hz. After that, Feedback, Depth and Low Gain make the next biggest differences. At default left and right are largely independent, so it sounds wide.
In other words, the main points:
- 11 of 11 tested controls measurably change the sound.
- Biggest lever beyond mix and level: Speed, 37.6× the smallest change that matters (amplitude-LFO rate 0.28 → 10.02 Hz).
- At default: stereo width 0.64, output -29.5 dBFS RMS.
- Main caveat: the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response.
- Still to measure: T1, T6, T7 (see
TESTS_NEEDED.md).
Show code
show_knobs('Vintage Flanger 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('Vintage Flanger 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.
Depth · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 0.0102 at raw 0 to 43.1 at raw 127.
Speed · longSine. Played: a steady 440 Hz sine. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.117 at raw 29 to 0.221 at raw 58.
Speed · sustainedStereo. Played: a held chord, one note per channel. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.353 at raw 29 to 1.08 at raw 132, dipping to 0.235.
Spread · stereoRouting. Played: bursts sent left only, right only, both in phase and both out of phase. The line is dB L/R isolation: how well left and right are kept apart; higher means less bleed; here it barely moves (about -64.4 throughout).
Type · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 31.9 at raw 0 to 36.4 at raw 2, peaking at 43.7.
Vintage Flanger 3¶
Show code
show_card('Vintage Flanger 3')
Vintage Flanger 3: what the measurements say¶
Recap. A modulation effect with 11 tested controls, 11 of which measurably change the sound. Beyond mix and level, the biggest lever is Speed: amplitude-LFO rate 0.28 → 10.01 Hz. Measured with 104 captures: 54 on the main sweep + tone probe (one control at a time), 26 on matched probes (spectralSweep ×15, sustainedStereo ×5, impulseTail ×3, stereoRouting ×3), 24 two-control pairs.
Technical explanation. At default settings: output -29.1 dBFS RMS (crest 17.9 dB); stereo width 0.61, L/R correlation +0.27; spectral tilt -0.38 dB/octave; 73% of the impulse response's energy in its first 5 ms; harmonics H2 -78 dB, H3 -53 dB re the linear response.
Structure:
- pitch LFO 0.78 Hz, 31 cents peak-to-peak, L/R phase +14°
- amplitude LFO 0.78 Hz, depth 0.27
- crosstalk L→R -39 dB, R→L -33 dB
Two-control pairs captured: Depth×Low Gain, Feedback×Depth, Feedback×Low Gain, Speed×Depth, Speed×Feedback, Speed×Low Gain (interaction analysis in the main notebook).
Caveats:
- the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response
Plain explanation: The control to reach for first is Speed: amplitude-LFO rate 0.28 → 10.01 Hz. After that, Feedback, Depth and Low Gain make the next biggest differences. At default left and right are largely independent, so it sounds wide.
In other words, the main points:
- 11 of 11 tested controls measurably change the sound.
- Biggest lever beyond mix and level: Speed, 37.6× the smallest change that matters (amplitude-LFO rate 0.28 → 10.01 Hz).
- At default: stereo width 0.61, output -29.1 dBFS RMS.
- Main caveat: the LFO runs during the sweep, so the frequency-response features are averages over LFO phase, not a fixed response.
- Still to measure: T1, T6, T7 (see
TESTS_NEEDED.md).
Show code
show_knobs('Vintage Flanger 3')
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('Vintage Flanger 3')
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.
Depth · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 0.0102 at raw 0 to 42.8 at raw 127.
Speed · longSine. Played: a steady 440 Hz sine. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.117 at raw 29 to 0.221 at raw 58.
Speed · sustainedStereo. Played: a held chord, one note per channel. The line is Hz LFO rate: how many times a second the modulation cycles; here it goes from 0.353 at raw 29 to 1.08 at raw 132, dipping to 0.235.
Spread · stereoRouting. Played: bursts sent left only, right only, both in phase and both out of phase. The line is dB L/R isolation: how well left and right are kept apart; higher means less bleed; here it barely moves (about -64.4 throughout).
Type · sustainedStereo. Played: a held chord, one note per channel. The line is cents pitch swing: how far the pitch bends, peak to peak (100 cents = one semitone); here it goes from 31.8 at raw 0 to 36.4 at raw 2, peaking at 43.1.
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.