A unison is a setting available on certain instruments that makes the instrument play at 2 different frequencies simultaneously. This setting was previously known as "chorus", and then as "interval".

Unisons are only supported on Chip Wave, Harmonics, Picked String, and Custom Chip, with Pulse Width, Spectrum, and Basic Noise being supported only in Ultrabox and its forks (Abyssbox, Unbox, BariBox, and Slarmoo's Box).

Unison List

Unison Details Code Details Applicable Beepmods
Union (None) No unison effects. Voices: 1, Spread: 0.0, Offset: 0.0, Expression: 1.4, Sign: 1.0 All Beepmods
Shimmer A unison that utilizes a technique where if two frequencies are very close together in pitch, it causes a shimmering sound, hence the name. Voices: 2, Spread: 0.018, Offset: 0.0, Expression: 0.8, Sign: 1.0 All Beepmods
Hum This unison sounds like a bolder Shimmer. Voices: 2, Spread: 0.045, Offset: 0.0, Expression: 1.0, Sign: 1.0 All Beepmods
Honky Tonk This unison spreads the voices enough to where they don't shift but don't sound dissonant. Voices: 2, Spread: 0.09, Offset: 0.0, Expression: 1.0, Sign: 1.0 All Beepmods
Dissonant As the name suggests, Dissonant spreads the voices a bit too far and they clash in pitch. Voices: 2, Spread: 0.25, Offset: 0.0, Expression: 0.9, Sign: 1.0 All Beepmods
Fifth This unison uses the offset and spread to place a voice seven semitones above the primary voice which remains on the base note. Voices: 2, Spread: 3.5, Offset: 3.5, Expression: 0.9, Sign: 1.0 All Beepmods
Octave Akin to Fifth, Octave uses the same technique to place a voice an octave (12 semitones) above the other. Voices: 2, Spread: 6.0, Offset: 6.0, Expression: 0.8, Sign: 1.0 All Beepmods
Bowed Very similar to Shimmer with the one main difference being that the "Sign" is negative, which causes the voices to make an "arch-like" sound since the other voice's wave is flipped. Voices: 2, Spread: 0.02, Offset: 0.0, Expression: 1.0, Sign: -1.0 All Beepmods
Piano This unison puts the voices very close together. The smaller difference in pitch means it'll take longer for a full "shift" to finish. Voices: 2, Spread: 0.01, Offset: 0.00, Expression: 1.0, Sign: 0.7 BeepBox, JummBox, CardboardBox, Dogebox, BluBox, SynthBox, Wackybox, TodBox, WeebBox, NintariBox, GoldBox, MicroBox, PaandorasBox, Thurmbox, Blockbox, FamiliarBox, FoxBox, BluBox Desktop, MultiplayerBox, MarioPaintBox, UltraBox, Midbox, Dogebox2, AbyssBox, Unbox, BariBox, Slarmoo's Box
Warbled It's very similar to Dissonant. Voices: 2, Spread: 0.25, Offset: 0.05, Expression: 0.9, Sign: -0.8 JummBox, WeebBox, SynthBox, CardboardBox, PaandorasBox, GoldBox, MarioPaintBox, NintariBox, UltraBox, Midbox, Dogebox2, AbyssBox, Unbox, BariBox, Slarmoo's Box
Hecking Gosh It sounds like a combination of Octave, Fifth, and Dissonant. Voices: 2, Spread: 6.25, Offset: -6.0, Expression: 0.8, Sign: -0.7 GoldBox, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
this sounds so bad A stranger offset unison with a silent secondary voice. Voices: 2, Spread: -5.0, Offset: -0.5, Expression: 1.0, Sign: -5.0 Wackybox
Error A unison with an odd spread which still manages to deliver a harmonized sound. Voices: 2, Spread: 9.5, Offset: 0.0, Expression: 1.0, Sign: 1.3 TodBox
Spinner A unison similar to Shimmer. Voices: 2, Spread: 0.02, Offset: 0.0, Expression: 1.0, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Detune This unison only uses one voice. Instead, it detunes the pitch of the voice slightly higher so that when combined with surrounding instruments, it fakes the sound of a unison. Voices: 1, Spread: 0.0, Offset: 0.25, Expression: 1.0, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Rising A unison that is very dissonant. Voices: 2, Spread: 1.0, Offset: 0.7, Expression: 0.95, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Vibrate This unison is similar to Fifth but offset a bit higher. Voices: 2, Spread: 3.5, Offset: 7.0, Expression: 0.975, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Fourths A unison that is simultaneously harmonizing and dissonant. Voices: 2, Spread: 4.0, Offset: 4.0, Expression: 0.95, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Bass This unison only uses one voice, which is transposed seven semitones downwards. Voices: 1, Spread: 0.0, Offset: -7.0, Expression: 1.0, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Dirty This unison raises the volume of the instrument and slightly offsets its pitch higher. Voices: 2, Spread: 0.0, Offset: 0.1, Expression: 0.975, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Stationary Similar to Fifth, but with no offset. Voices: 2, Spread: 3.5, Offset: 0.0, Expression: 0.9, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Recurve This unison has an extremely miniscule amount of spread. Voices: 2, Spread: 0.005, Offset: 0.0, Expression: 1.0, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Voiced Same as Error with the only difference being the sign. Voices: 2, Spread: 9.5, Offset: 0.0, Expression: 1.0, Sign: 1.0 ModBox, BruceBox, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Fluctuate This unison splits the voices between two octaves. Voices: 2, Spread: 12.0, Offset: 0.0, Expression: 1.0, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Thin A unison that offsets the instrument's pitch more than four octaves higher. Voices: 1, Spread: 0.0, Offset: 50.0, Expression: 1.0, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Inject A combination of Octave, Stationary, and Detune. Voices: 2, Spread: 6.0, Offset: 0.4, Expression: 1.0, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Askewed Lowers the volume of the main voice and detunes it upwards half a semitone. Voices: 1, Spread: 0.0, Offset: 0.42, Expression: 0.7, Sign: 1.0 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Resonance A combination of Bowed and Recurve. Voices: 2, Spread: 0.0025, Offset: 0.1, Expression: 0.8, Sign: -1.5 Unknown, UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
FART A bold unison with harmonization. Voices: 2, Spread: 13, Offset: -5, Expression: 1.0, Sign: -3 UltraBox, AbyssBox, Unbox, BariBox, Slarmoo's Box
Hyper A unison inspired by Shimmer. Voices: 2, Spread: 0.03, Offset: -0.02, Expression: 0.85, Sign: 0.7 Midbox
Peak Similar to Fluctuate except the voices are offset upwards an octave and have a slight shifting sound. Voices: 2, Spread: 12.038, Offset: 12.01, Expression: 0.85, Sign: 0.9 Midbox
Deep Shift The same as Peak but offset much lower. Voices: 2, Spread: 12.03, Offset: -17.01, Expression: 0.85, Sign: 1.2 Midbox
Broke Similar to Askewed and Detune, but the pitch is offset downwards instead and has a barely-noticable shifting sound. Voices: 2, Spread: 0.000211, Offset: -0.3, Expression: 0.8, Sign: 1.0 Midbox
Vary A unison similar to Piano. Voices: 2, Spread: 0.0018, Offset: 0.0, Expression: 0.85, Sign: 1.6 Midbox
Energetic This unison uses dissonance and tuning for harmonizing. Voices: 2, Spread: 6.15, Offset: 6.435, Expression: 0.85, Sign: 0.9 Midbox
Lone Fifth Transposes the main voice seven semitones upwards. Voices: 1, Spread: 0.0, Offset: 7.0, Expression: 1.4, Sign: 0.9 Midbox
Alternate Fifth The same as Fifth, but it's the fifth note below the placed note. Voices: 2, Spread: 2.5, Offset: -2.5, Expression: 0.9, Sign: 0.9 Midbox
Offtune As the name implies, this unison is dissonant. Voices: 2, Spread: 0.40, Offset: 0.40, Expression: 0.9, Sign: 0.9 Midbox
Hold This unison shifts heavily and slowly. Voices: 2, Spread: 0.003, Offset: 0.0, Expression: 0.8, Sign: -2.5 Midbox
Buried This unison places the voices three octaves lower and shifts slightly. Voices: 2, Spread: 0.03575, Offset: -36.0, Expression: 1.4, Sign: 1.0 Midbox
Corrupt This unison places and spreads the voices very high. Voices: 2, Spread: 18.0, Offset: 48.0, Expression: 0.7, Sign: 0.7 Midbox
Weird Octave Same as Octave but dissonance is utilized to add harmonizing. Voices: 2, Spread: 5.85, Offset: 5.85, Expression: 0.75, Sign: 1.0 Midbox

Custom Unisons

UltraBox, Unbox, AbyssBox, BariBox, and Slarmoo's Box allow you to edit unisons to make your own. Next to the unison selection box, there will be an arrow. Clicking this will let you change the five unison properties.

Explanation

The unison itself can have 5 properties:

Voices: Unisons use "voices" as a way to say "How many duplicates of this instrument will be used in this unison?". Typically, this can only be 1 (Lone Fifth, Askewed) or 2 (most other unisons use this). These unisons are then offset and spread apart in pitch to create various sounds, such as shimmering (Hum, Hold), or harmonization (Fifth, Fourths, Weird Octave).

Spread: The distance between both voices to the placed note in semitones. A small amount of spread causes the voice's waves to shift in and out from each other, causing a shimmering effect (Shimmer, Piano, Recurve). More spread will cause the voices to sound dissonant (Dissonant, Rising, Offtune) up until the voices sound like separate notes (Fifth, Octave, Stationary, Alternate Fifth). This effect only works properly with two voices. However, in some BeepMods, using only one voice can have some unique sound artifacts, as the sound the unison makes when using this setting would sound like the pitch of the voice splitting in two.

Offset: The amount both voices are offset by in semitones (Bass, Thin, Buried). A more obscure but useful use case for this is to use it as an extended pitch shift slider, with the power to detune and set the instrument's pitch very high and low. When using the unison envelope target, this is the setting being affected, and it is changed similar to that of the detune/pitch shift envelope targets.

Expression: The volume of the unison. This setting is called "Volume" on custom unisons for understandability. Can be used to mix the unison in case it causes the instrument to be too loud. Can also be used as a second volume slider to the instrument.

Sign: A volume multiplier only applied to the second voice of the unison. Negative signs make the wave of the second voice invert, meaning both waves will shift through each other and also cause an arc-like shimmering effect (Bowed, Resonance).