GB-Wave, GB-Pulse, and GB-Noise

Choose GB-WAVE, GB-PULSE, or GB-NOISE in the Instrument Type row. These are three independent synth types, not Stack modes. They need no sample files and can occupy any of the 64 instrument slots, with different settings in each slot.

Use GB-Pulse for duty-cycle leads, GB-Wave for a custom 4-bit waveform, and GB-Noise for percussion. Choose Chiptune instead when you want its broader waveform selection, noise burst, and built-in arpeggio-speed control, or Stack for chords and detuned layers.

Try a pulse lead

1. Assign an instrument to a Phrase note and open that instrument.
2. Change Type to GB-PULSE. Keep DUTY at 50%, ENVELOPE at F0, and LENGTH /256S at 00.
3. Return to Phrase and play the note. It holds until replaced or stopped.
4. Add ARP 4700 to cycle the base note, major third, and fifth.
5. Try SIP 0001 on a later step: the sounding voice changes to 25% duty. Triggering a new note restores the instrument's saved 50% duty.

All numeric values below are hexadecimal unless stated otherwise. On digit-editable fields, hold Enter, choose a digit with Left / Right, and adjust it with Up / Down.

Shared controls

Field	Values	Default	Meaning
VOLUME	00–FF	80	Voice output gain, separate from the pulse/noise envelope or wave output level
TRANSPOSE	−24 to +24, decimal	0	Semitone offset; Pulse and Wave only
LENGTH /256S	Pulse/Noise 00–40; Wave 000–100	00 / 000	Countdown in 1/256-second units; zero disables automatic length stopping
TABLE	--, 00–1F	--	Attached instrument Table
AUTOMATION	NO, YES	NO	Uses the instrument-table automation mode

For example, length 40 is 64/256 seconds (one quarter second), not 40 tracker ticks. Envelope, sweep, and length clocks are independent of song tempo. Note Off and GOF stop a GB voice immediately; KIL uses its tracker-tick delay.

GB-Pulse

Pulse keeps duty, envelope, length, sweep, and Table controls in one instrument. This example changes duty from its default 50% to 75%.

Field	Values	Default	Meaning
DUTY	12.5%, 25%, 50%, 75%	50%	Four pulse patterns; SIP addresses them as 00–03
ENVELOPE	00–FF	F0	Initial level, direction, and automatic level-step period
SWEEP	00–7F	00	Pulse frequency-period sweep

The envelope byte is VVVVDPPP in binary: V is the starting level 0–15, D selects increase (1) or decrease (0), and P is the number of 1/64-second intervals between level steps. P = 0 disables automatic steps. F0 holds the maximum envelope level; F2 starts at maximum and decreases every 2/64 seconds. Values 00–07 disable the pulse/noise DAC and produce no sound.

The sweep byte is 0PPPDSSS: P sets the sweep period in 1/128-second units, D chooses subtraction (1) or addition (0) to the frequency period, and S is the right-shift amount used to calculate the change. Zero period disables periodic sweep. A sweep that overflows the supported period stops the voice. Keep 00 while editing a steady lead.

GB-Wave

Each digit under Wave RAM is one sample. Here the fourth point has changed from 3 to 4; scroll down for the remaining wave and Table rows.

Field	Values	Default	Meaning
OUTPUT LEVEL	MUTE, 100%, 50%, 25%	100%	Wave-sample bit shift; separate from VOLUME
00-03 through 1C-1F	Four digits per row, each 0–F	See below	32 waveform samples, four samples per row

The default waveform is:

0123 4567 89AB CDEF FEDC BA98 7654 3210

Each digit is one 4-bit sample, not part of an ordinary 16-bit amplitude. Editing 00-03 from 0123 to 012F changes only sample 03. The eight rows form one repeating waveform. Wave data is saved inside the instrument.

There is no Pulse/Noise-style envelope or sweep field on GB-Wave. Use Table VOL or SIP steps for level changes. OUTPUT LEVEL reduces sample precision by bit shifting; VOLUME controls the subsequent voice gain.

GB-Noise

Noise shape changes the generator's clock and width. This example edits the default shape 35 to 36.

Field	Values	Default	Meaning
SHAPE (NR43)	00–FF	35	Noise clock shift, register width, and divisor code
ENVELOPE	00–FF	F2	Same encoding as GB-Pulse

SHAPE (NR43) is SSSSWDDD in binary: S is the clock shift, W chooses a 7-bit (1) or 15-bit (0) noise register, and D is the divisor code. For example, 35 and 3D use the same shift/divisor with different widths. Clock shifts E and F stop noise-clock advancement; choose a lower shift for changing noise.

Notes trigger the sound but do not set its pitch. Change SHAPE (NR43) or use SIP 00bb to alter the noise clock. There is no transpose control, and ARP, LEG, PFT, PSL, and VIB do not affect GB-Noise.

Native effects

Type	Instrument effects
GB-Pulse / GB-Wave	ARP, GOF, LEG, PAN, PFT, PSL, SIP, VIB, VOL
GB-Noise	GOF, PAN, SIP, VOL

Common Phrase/Table commands such as DLY, KIL, TBL, and IRT remain available in their respective contexts. GB types do not implement CSH, RTG, or Stack chord commands. The command reference lists page restrictions and parameter timing.

On GB types, VOL aabb applies bb immediately and ignores aa; it does not use Chiptune's volume-ramp timing. Pulse/Wave ARP advances on tracker ticks. Native PAN supports intermediate positions, not just hard left/right.

SIP parameter map

SIP aabb changes the sounding voice, not the saved instrument. A new note restores the saved settings. Unlisted indices are ignored.

aa	GB-Pulse	GB-Wave	GB-Noise
00	Duty 00–03	Output level 00–03 (mute/full/half/quarter)	Noise shape byte
01	Transpose, signed byte clamped to −24…+24	Same	Ignored
02	Volume 00–FF	Same	Same
03	Length 00–40	Length 00–FF	Length 00–40
04	Envelope byte	Ignored	Envelope byte
05	Sweep 00–7F	Ignored	Ignored
10–2F	Ignored	Wave sample 00–1F, value 00–0F	Ignored

Wave's saved length can reach 100, but the one-byte SIP value reaches only FF. SIP 100F sets the first waveform point to F; SIP 2F00 sets its last point to 0. SIP 010C transposes Pulse or Wave up 12 semitones.

Voices and compatibility

GB instruments share eight track voices. A preset can play on several tracks; different GB presets can play on different tracks. A new note on the same track replaces its previous voice. The project is not constrained to a Game Boy's two-Pulse / one-Wave / one-Noise arrangement.

These synths implement GB-style period quantization, pulse patterns, wave RAM, noise registers, and frame-sequencer timing. They are not a full CPU/APU bus emulator: wave-RAM corruption, envelope zombie writes, and DIV-write quirks are not emulated. Native tracker effects are not LSDJ commands, and LSDJ-specific sequencing, wave synthesis, and kit playback are not supplied by these types. See LSDJ and other trackers before moving a project from another tracker.