The Yamaha YM2151, also known as the OPM Chip (Operator Type M), is a sound chip that uses FM synthesis for sound generation. It was notably used in a number of arcade system boards as well as the Sharp X68000 home computer.

It features 8 FM channels, with 4 operators each. Very similar to the YM2612 used in the Sega Genesis, but lacking SSG-EG. It also gains a coarser detune setting (DT2), a wider variety of options for LFO (broader speed range, and with a varying number of waveforms), and an AY/YM PSG style noise generator, usable on Channel 8's 4th operator.

'[#[Tools]
'[[DefleMask Tracker] (set to Arcade system, but do not use SP channels for legal entries)
'[[Furnace Tracker] (can set to YM2151 only)
'[[XPMCK] (the CPS1 system supports both the YM2151 and the OKIM6295, but please use the YM2151 only!)

'[#[Restrictions on submit]
Your submission should only use '[b]one'[/b] YM2151 chip. Not two, and certainly no other soundchips whatsoever. If you want to add more, consider submitting to the  '[[wildchip (format)[wildchip] or '[[VGM (format)[VGM] format.

Open questions:
'[ul['[li[Should formats other than .vgm be allowed (e.g. .mdx/.pdx for Sharp X68000)]'[li[Do we cap the chip clock rate between 3 MHz and 4 MHz? 3.58MHz seemed to be common for a lot of arcade titles, and 4MHz is what the X68000 uses. Furnace allows the user to toggle between these two settings.]]

'[#[Playback (for voting)]
Use vgmplay or the latest in_vgm plugin Winamp for .vgm files. You should make sure to set the emulation core to NukedOPM, if possible.

'[#[See also]
'[[Format]