Distortion: every effect side by side

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 Drive 0 and 43% at 127; it is within 1 dB of its ceiling by Drive 47, 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 Drive 0 and 41% at 127; it is within 1 dB of its ceiling by Drive 15, 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 Drive 0 and 43% at 127; it is within 1 dB of its ceiling by Drive 31, 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-Drive 0 and 40% at 127; it is within 1 dB of its ceiling by Dist-Drive 31, 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 Drive 0 and 45% at 127; it is within 1 dB of its ceiling by Drive 31, 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-Drive 0 and 40% at 127; it is within 1 dB of its ceiling by Dist-Drive 15, 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 Drive 0 and 41% at 127; it is within 1 dB of its ceiling by Drive 31, 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-Drive 0 and 38% at 100; it is within 1 dB of its ceiling by Over-Drive 37, 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 Drive 0 there are 45 measurable products at −6 dBFS and 0 at −42 dBFS; at Drive 127 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 Drive 0 there are 10 measurable products at −6 dBFS and 3 at −42 dBFS; at Drive 127 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-Drive 0 there are 8 measurable products at −6 dBFS and 4 at −42 dBFS; at Over-Drive 100 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 Drive 31 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; at Drive 31 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; at Drive 31 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; at Dist-Drive 31 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; at Drive 31 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; at Dist-Drive 31 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; at Drive 31 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; at Over-Drive 25 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 Drive 0 the reading stays at the bypass floor: no interaction between the notes.
• From Drive 31 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.

What it shows. Every pair of controls that was recorded at all four corners, each control at its low and its high test setting, for the Distortion effects. For each pair: what the second control does to the tone with the first one low, what it does with the first one high, and how far apart those two are as a share of the larger.

How to read it. One dot is one pair; hover for which. At the left edge the second control does the same thing wherever the first one is, so the two simply add. At the right edge it does something at one end of the first control and nothing, or the opposite, at the other. The same pairs are drawn as curves on each effect's sheet above, under two controls together.

What it found.

• Of 37 pairs in which the second control changes the tone, 29 are ones where the first control changes what the second does.
• The pair furthest apart is Ratio with Drive on Comp + Dist.
• Tone only is compared, smoothed over about two thirds of an octave, so a change in timing alone does not show here.
• On an effect that moves by itself part of any gap is the movement caught at a different moment.