Skip to main content

Effects and Mixing

Add depth and character to your music with built-in effects.

Filter (CUTOFF + RESONANCE)​

Low-pass filter removes high frequencies. Lower CUTOFF = darker, warmer sound:

INSTRUMENT bass:
    TYPE SYNTH
    WAVE SAW
    CUTOFF 600         # only frequencies below 600 Hz pass through
    RESONANCE 100      # boost around the cutoff point
    ADSR 5 40 300 120
    VOLUME 220

You can override CUTOFF per-note for expressive playing:

SEQUENCE bass_filter:
    PLAY bass C2 1 200 CUTOFF:400    # dark
    PLAY bass C2 1 200 CUTOFF:1200   # bright
    PLAY bass C2 1 200 CUTOFF:600    # back to normal

Reverb​

Adds space and ambience. Value 0–255 (0 = dry, 255 = fully wet):

INSTRUMENT pad:
    TYPE SYNTH
    WAVE SIN
    REVERB 150
    ADSR 200 100 400 300
    VOLUME 160

Delay​

Echo effect with configurable time and feedback:

INSTRUMENT lead:
    TYPE SYNTH
    WAVE TRIANGLE
    DELAY 300 150      # 300ms delay, 150 feedback (0-255)
    ADSR 10 30 200 100
    VOLUME 180

Higher feedback = more echo repeats. Keep below 200 to avoid runaway feedback.

warning

Delay feedback values above 200 can cause audio to build up and clip. Start low and increase gradually.

Panning (PAN)​

Position instruments in the stereo field:

INSTRUMENT bass:
    TYPE SYNTH
    WAVE SAW
    PAN 100            # slightly left
    ...

INSTRUMENT lead:
    TYPE SYNTH
    WAVE TRIANGLE
    PAN 180            # slightly right
    ...

Values: 0 = hard left, 127 = center, 255 = hard right.

note

Stereo panning requires ESP32 with an I2S DAC. Arduino Uno is mono only.

Glide (Portamento)​

Slide between notes instead of jumping:

INSTRUMENT lead:
    TYPE SYNTH
    WAVE SAW
    GLIDE 100          # 100ms slide between notes
    ADSR 10 30 200 100
    VOLUME 180

LFO (Low Frequency Oscillator)​

Add movement with slow modulation:

INSTRUMENT wobble:
    TYPE SYNTH
    WAVE SAW
    CUTOFF 2000
    VOLUME 200
    ADSR 5 40 300 120
    LFO 4.0 120 VOLUME     # tremolo — volume wobbles at 4 Hz
    LFO 2.0 30 PITCH       # vibrato — pitch wobbles at 2 Hz
    LFO 1.5 800 CUTOFF     # wah — filter sweeps at 1.5 Hz
tip

LFO on CUTOFF is the secret weapon for electronic music — it creates the classic "wah-wah" and acid bass sounds. Make sure the instrument has CUTOFF set first.

Each instrument supports up to 4 LFOs (one per target: VOLUME, PITCH, CUTOFF, PAN).

Unison (Fat Sound)​

Stack detuned copies of an oscillator:

INSTRUMENT supersaw:
    TYPE SYNTH
    WAVE SAW
    VOICES 3           # 3 oscillator copies
    DETUNE 20          # spread 20 cents apart
    CHORUS 80          # add chorus width
    ADSR 10 50 200 100
    VOLUME 180
warning

VOICES > 2 uses significant RAM on Arduino Uno (ATmega328 has only 2 KB). Stick to 1–2 voices on AVR targets, or use ESP32.

Volume Dynamics​

VELOCITY_CURVE​

Automatically create crescendo/decrescendo across notes:

SEQUENCE buildup:
    VELOCITY_CURVE CRESCENDO 40 230 6
    PLAY lead C4 0.5
    PLAY lead D4 0.5
    PLAY lead E4 0.5
    PLAY lead F4 0.5
    PLAY lead G4 0.5
    PLAY lead A4 1

FADE_IN / FADE_OUT​

Fade the entire mix:

FADE_IN 4
LOOP 4:
    PLAY_TOGETHER:
        PLAY_SEQUENCE melody
        PLAY_PATTERN drums
FADE_OUT 8
LOOP 2:
    PLAY_SEQUENCE outro

Mixing Tips​

  1. Bass instruments — keep PAN centered (127), CUTOFF low (400–800)
  2. Lead instruments — pan slightly off-center, add REVERB or DELAY for space
  3. Hi-hats — pan slightly (100 or 160), keep VOLUME lower than kick/snare
  4. Use VELOCITY_CURVE for buildups before a chorus
  5. LFO on CUTOFF creates movement in pads and bass lines
info

All effect values are compile-time constants — they get baked into the C++ output with zero runtime overhead on the MCU.