HOW WE CHECK
Accuracy, chip by chip.
Every chip here is checked against real hardware or a cycle-accurate reference emulator, not just listened to and approved. Most people only need the status badge on each chip below - the rest of this page is the evidence, for anyone who wants to check our work themselves.
Every number below comes from the conformance harness that runs before each release, never typed by hand. Four levels per chip: how closely the digital output matches a reference emulator, which community test ROMs pass, how closely the analog stage after the chip's DACs matches a real unit, and how much of the chip the shipped driver reaches. The method behind every section is in CONFORMANCE.md, and each chip's own sheet has the full detail.
The Commodore 64 and three extra boards found only in the library - the Konami VRC6, the AY-3-8910 and the Yamaha YM2151 - are checked here too, even though none of them is one of the four pickable consoles.
Famicom Ricoh 2A03
Digital parity
Compared with Nes_Snd_Emu 0.1.7 (blargg): 3.9 % identical (3,577,340 of 92,173,307 cycles), 13 of 13 logs with any divergence.
First divergence: script-dmc, cycle 0, tri - ours 15, the oracle's 0.
Compared with Mesen 2 (b9fa69d, 2026-06-04): 65.8 % identical (60,662,173 of 92,173,307 cycles), 13 of 13 logs with any divergence.
First divergence: script-dmc, cycle 0, tri - ours 15, the oracle's 0.
Test ROMs
29 of 29 test ROMs pass.
- apu_test/1-len_ctr: pass
- apu_test/2-len_table: pass
- apu_test/3-irq_flag: pass
- apu_test/4-jitter: pass
- apu_test/5-len_timing: pass
- apu_test/6-irq_flag_timing: pass
- apu_test/7-dmc_basics: pass
- apu_test/8-dmc_rates: pass
- apu_reset/4015_cleared: pass
- apu_reset/4017_timing: pass
- apu_reset/4017_written: pass
- apu_reset/irq_flag_cleared: pass
- apu_reset/len_ctrs_enabled: pass
- apu_reset/works_immediately: pass
- dmc_tests/buffer_retained: pass
- dmc_tests/latency: pass
- dmc_tests/status: pass
- dmc_tests/status_irq: pass
- apu_2005/01.len_ctr: pass
- apu_2005/02.len_table: pass
- apu_2005/03.irq_flag: pass
- apu_2005/04.clock_jitter: pass
- apu_2005/05.len_timing_mode0: pass
- apu_2005/06.len_timing_mode1: pass
- apu_2005/07.irq_flag_timing: pass
- apu_2005/08.irq_timing: pass
- apu_2005/09.reset_timing: pass
- apu_2005/10.len_halt_timing: pass
- apu_2005/11.len_reload_timing: pass
Analog stage
The mixer is measured against a real console's own recordings; the output filters are not measured yet.
- square: -32.7 dB (console -32.2 dB)
- triangle: -33.0 dB (console -30.9 dB)
- noise: -13.8 dB (console -16.2 dB)
- dmc: -31.0 dB (console -27.2 dB)
Driver coverage
The shipped driver reaches 4 of the chip's 5 voices.
Game Boy DMG APU
Digital parity
Compared with Gb_Snd_Emu 0.1.4 (blargg): 57.3 % identical (83,100,392 of 145,122,916 cycles), 7 of 7 logs with any divergence.
First divergence: script-envelopes, cycle 419432, ch1 - ours 0, the oracle's 15.
Compared with SameBoy (DMG-B): 94.8 % identical (137,606,353 of 145,122,916 cycles), 6 of 7 logs with any divergence.
First divergence: script-envelopes, cycle 427391, ch1 - ours 15, the oracle's 0.
Test ROMs
12 of 12 test ROMs pass.
- dmg_sound/01-registers: pass
- dmg_sound/02-len_ctr: pass
- dmg_sound/03-trigger: pass
- dmg_sound/04-sweep: pass
- dmg_sound/05-sweep_details: pass
- dmg_sound/06-overflow_on_trigger: pass
- dmg_sound/07-len_sweep_period_sync: pass
- dmg_sound/08-len_ctr_during_power: pass
- dmg_sound/09-wave_read_while_on: pass
- dmg_sound/10-wave_trigger_while_on: pass
- dmg_sound/11-regs_after_power: pass
- dmg_sound/12-wave_write_while_on: pass
Analog stage
Not measured yet. This stage is a placeholder, not a result.
Driver coverage
The shipped driver reaches 4 of the chip's 4 voices.
Mega Drive YM2612 + SN76489
Digital parity
Compared with Nuked-OPN2 1.0.12 (Nuke.YKT): 100.0 % identical (2,566,533,768 of 2,566,533,768 cycles), 0 of 10 logs with any divergence.
First divergence: none, every measured cycle is identical.
Compared with MAME sn76496 (Sega VDP PSG, 76c7d197): 90.5 % identical (2,321,902,638 of 2,566,533,768 cycles), 5 of 10 logs with any divergence.
First divergence: script-psg-edges, cycle 8054100, psg1 - ours 15, the oracle's 0.
Test ROMs
No community test ROM suite exists for this chip yet.
Analog stage
Not measured yet. This stage is a placeholder, not a result.
Driver coverage
The shipped driver reaches 4 of the chip's 10 voices.
Super Famicom S-DSP
Digital parity
Compared with snes_spc 0.9.0 (blargg): 100.0 % identical (29,081,600 of 29,081,600 cycles), 0 of 6 logs with any divergence.
First divergence: none, every measured cycle is identical.
Test ROMs
No community test ROM suite exists for this chip yet.
Analog stage
Not measured yet. This stage is a placeholder, not a result.
Driver coverage
The shipped driver reaches 4 of the chip's 8 voices.
LIBRARY ONLY
C64 MOS 6581 SID
Digital parity
Compared with reSID-fp (libsidplayfp, drfiemost), as a 6581: 100.0 % identical (50,149,124 of 50,149,124 cycles), 0 of 13 logs with any divergence.
First divergence: none, every measured cycle is identical.
Compared with reSID-fp (libsidplayfp, drfiemost), as an 8580: 99.4 % identical (49,841,861 of 50,149,124 cycles), 2 of 13 logs with any divergence.
First divergence: script-combined, cycle 98781, osc1 - ours 7, the oracle's 3.
Also checked against a real 6581 (6581R4AR_3789_14): the combined-waveform bits before the DAC.
- saw+triangle: 82.0 % of entries exact (3358 of 4096), 1500 of 32768 bits differ.
- pulse+triangle: 83.1 % of entries exact (3404 of 4096), 922 of 32768 bits differ.
- pulse+saw: 75.0 % of entries exact (3072 of 4096), 1623 of 32768 bits differ.
- pulse+saw+triangle: 94.1 % of entries exact (3854 of 4096), 457 of 32768 bits differ.
Test ROMs
14 of 14 test ROMs pass.
- busvalue/busvalue: pass
- envelope/testADSRDelayBug: pass
- osc_topbit/osc_topbit_test_noise_old: pass
- osc_topbit/osc_topbit_test_pulse_old: pass
- osc_topbit/osc_topbit_test_triangle_old: pass
- osc3-wave0/osc3-wave0: pass
- oscinit/allinit: pass
- oscinit/noiseinit: pass
- oscinit/oscinit: pass
- resid-test/envrate: pass
- resid-test/envsustain: pass
- resid-test/envtime: pass
- resid-test/noisetest: pass
- ringmod/ringmodtest: pass
Analog stage
A profile built from public documentation, unmeasured against a real unit.
Driver coverage
The shipped driver reaches 3 of the chip's 3 voices.
LIBRARY ONLY
NES, Famicom (Konami VRC6 cartridges) Konami VRC6
Digital parity
Compared with Game_Music_Emu (Nes_Vrc6_Apu): 38.1 % identical (2,413,336 of 6,339,623 cycles), 7 of 8 logs with any divergence.
First divergence: script-all-three, cycle 17898, vp2 - ours 0, the oracle's 9.
Compared with Mesen 2 (b9fa69d, 2026-06-04), VRC6 audio: 90.4 % identical (5,732,469 of 6,339,623 cycles), 3 of 8 logs with any divergence.
First divergence: script-all-three, cycle 757716, vp1 - ours 75, the oracle's 0.
Test ROMs
No community test ROM suite exists for this chip yet.
Analog stage
Not measured yet. This stage is a placeholder, not a result.
Driver coverage
The shipped driver reaches 0 of the chip's 3 voices.
LIBRARY ONLY
NES, Famicom (Sunsoft 5B mapper: Gimmick!) AY-3-8910 / YM2149, first hosted as the Sunsoft 5B
Digital parity
Compared with Ayumi: 100.0 % identical (104,913 of 104,913 cycles), 0 of 5 logs with any divergence.
First divergence: none, every measured cycle is identical.
Compared with Game_Music_Emu (Ay_Apu): 100.0 % identical (104,913 of 104,913 cycles), 0 of 5 logs with any divergence.
First divergence: none, every measured cycle is identical.
Compared with Ayumi: 100.0 % identical (1,893,115 of 1,893,115 cycles), 0 of 7 logs with any divergence.
First divergence: none, every measured cycle is identical.
Compared with Game_Music_Emu (Ay_Apu): 74.4 % identical (1,407,646 of 1,893,115 cycles), 7 of 7 logs with any divergence.
First divergence: envelope-and-tone, cycle 1264, a - ours 0, the oracle's 32.
Test ROMs
No community test ROM suite exists for this chip yet.
Analog stage
Not measured yet. This stage is a placeholder, not a result.
Driver coverage
The shipped driver reaches 0 of the chip's 3 voices.
LIBRARY ONLY
Arcade and home-computer boards (Sharp X68000, many 1980s Taito/Konami/Sega/Capcom boards) Yamaha YM2151 (OPM)
Digital parity
Compared with Nuked-OPM 1.0 (Nuke.YKT): 100.0 % identical (7,132,062 of 7,132,062 cycles), 0 of 9 logs with any divergence.
First divergence: none, every measured cycle is identical.
Compared with ymfm (Aaron Giles): 20.7 % identical (1,475,224 of 7,132,062 cycles), 9 of 9 logs with any divergence.
First divergence: algorithms, cycle 208000, l - ours 0, the oracle's 774.
Compared with ymfm (Aaron Giles): 33.2 % identical (855,586 of 2,575,891 cycles), 6 of 6 logs with any divergence.
First divergence: dt2-mul-zero, cycle 136000, l - ours 0, the oracle's 798.
Compared with Nuked-OPM 1.0 (Nuke.YKT): 100.0 % identical (2,575,891 of 2,575,891 cycles), 0 of 6 logs with any divergence.
First divergence: none, every measured cycle is identical.
Test ROMs
No community test ROM suite exists for this chip yet.
Analog stage
Not measured yet. This stage is a placeholder, not a result.
Driver coverage
The shipped driver reaches 0 of the chip's 2 voices.
Regenerated on every push from the harness's own numbers: pnpm --filter chipvoice-conform status writes this page's data file alongside the README board and every chip's sheet.