X68000

The YM2608 was made by Yamaha and got used inside lots of Soundcards for several different (mostly japanese) Homecomputers aswell as a few Arcade Games. It is also known as the OPNA (FM Operator Type N-A).

Technical Specifications

• Channels: 16
• Channels 1-6: FM Sound Synthesis with 4 Operators. Also comes with a build-in envelope Generator (ADSR)
• Channels: 7-9: Squarewave & Noise Synthesis (compatible to the YM2149)
• Channels 10-15: Rhythm Channels. Each of the 6 channels plays a predefined ADPCM Sample. Available were the following instruments: A Bass Drum, Snare Drum, Cymbal, Closed Hi-Hat, Tom Tom & Rimshot.
• Channel 16: 4-bit ADPCM Sample Playback (with up to 256kb Sample DRAM), Sample Rate 2 – 16 kHz. The difference to the channels above is that you can actually upload one or more samples yourself.
• Stereo: Only the FM Channels feature Stereo. The Squarewave, Noise and Rhythm Channels are Mono
• DAC: External, the 2 Channel YM3016 Stereo DAC
• Has an LFO
• Datasheet is available here (Link)

Used in

Home Computers

• NEC PC-8801 FA (with the Sound Board II)
• NEC PC-8801 MA (with the Sound Board II)
• NEC PC-88 VA2 (with the Sound Board II)
• NEC PC-88 VA3 (with the Sound Board II)
• it was also optionally available in other PC-88 Computers.

Soundcards

• NEC PC-8801-23 (for PC-88 computers, its actually the Sound Board II)
• NEC PC-9801-76 (for PC-98 computers)
• NEC PC-9801-86 (for PC-98 computers)
• Mad Factory Otomichan (音美ちゃん) (for PC-98 computers)
• MSI (Idol Japan / Alpha Data) Speakboard (for PC-98 computers)
• Q-Vision Wave Master (for PC-98 computers)
• SIS Planning Amusement Soundboard ASB-01 (for PC-98 computers)
• Yamaha Sound Edge SW20-98 (for PC-98 computers)
• Yamaha Sound Edge SW20-PC (for IBM-PC computers)

Arcade Games

• Hatris
• Mechanized Attack
• Tecmo World Cup ‘90
• and a few others…

Special Applications

• Mad Factory Otomichan | This PC-98 Soundboard uses the YM2608 together with an YM3428, expanding the sound with 6 extra FM Channels.
• Q-Vision Wave Master | Additionally features a CS4231 and a WD33C93BJM
• SIS Planning Amusement Soundboard ASB-01 | This comes without the 256 KB ADPCM DRAM, which, I think, makes channel 16 not usable anymore. I’ve seen hacks though where people added the missing DRAM to the Card.
• Yamaha Sound Edge | The two soundcards feature a lot of additional chips, namely the YMF278B, an AD1848KP and a YSS205.

Variants

• YM2608B | This is the name that is actually printed on the chip.

Emulation

PC-88 & PC-98

• Hoot | Emulates both the PC-88 aswell as the PC-98 just fine. You can read more about Hoot over Here.
• S98 | a fileformat which actually contains logged music data which was recorded using an emulator. It’s playable in Winamp using th e S98amp Plugin from here.
• OVI | a fileformat which stores OPNA Music. You can play it with inFMPMD (Winamp Plugin) from here or with FMPMD2000 from here.

Arcade

• The Music of the Arcade Systems can be emulated with M1. M1 is a music player which is based on MAME and thus supports a lot of Arcade Games, although the Sega Mega-Play and Mega-Tech seem to be missing from it. More about M1 can be found here.