Ryder's MPC Tools

Build Akai MPC60 hard-disk images from folders of WAVs — and take apart the ones you already have.

Tested on hardware

What this is

A small Python toolchain for the Akai MPC60 / MPC60-II running from a ZuluSCSI or similar SCSI emulator. Point it at folders of samples and it produces a bootable multi-partition drive image with drum programs already built.

A 26-partition, 753 MB image built by these tools loads on an MPC60 and plays. The formats were reverse engineered from a working CompactFlash card and a real PROGRAM_.pgm, then verified against the machine.

Requires Python 3 and numpy. Nothing else.

The tools

tools/mpc60build.py

Folders of WAVs to a finished drive image. Converts to 40 kHz / 12-bit, builds and splits programs automatically, lays out FAT12 partitions, and budgets everything against the machine's sound memory rather than disk space.

tools/mpc60drive.py

Inspect and edit a drive. List what is on every partition, pull one out as a mountable image, drag files around in Finder, and write it back. Refuses a wrong-sized image rather than corrupting the partition next door.

tools/mpc60decompile.py

Take programs and samples apart field by field, with every undecoded field labelled UNKNOWN. Includes a diff that compares two programs — the fastest way to work out what is still not understood.

tools/mpc60conv.py

Samples on their own. WAV to SND and back, header inspection, and a verify that proves the codec round-trips a file byte-for-byte.

Quick start

One folder per partition. Subfolders inside a kit are just grouping — every WAV underneath gets used.

STAGING/
  Roland R-70/        -> becomes drive A
  AcidLab Miami/      -> drive B
  LSDJ/               -> drive C

python3 tools/mpc60build.py STAGING -o HD0_512.hda \
  --boot reference/boot.bin \
  --pgm-donor reference/donor.PGM \
  --snd-header reference/header.SND \
  --memory-kb 1400

python3 tools/mpc60drive.py list HD0_512.hda

Then copy HD0_512.hda to the root of the SD card. The filename matters — ZuluSCSI parses the SCSI ID and block size out of it. HD0_512.hda through HD6_512.hda; never HD7, that is the MPC's own controller.

The limits that actually bite

Budget against memory, not disk. This is the thing that wastes people's time on this machine — a 29 MB partition holds far more than the MPC can load at once.

Limit	Value	Why
Sound memory	750 KB / 1500 KB	12.8 or 25.6 seconds of audio. Stock or expanded.
Partition load	whole partition	The MPC appears to load every sound on a partition, not just a program's.
Partition size	~29 MB	FAT12 caps at 4084 clusters, at 8 KB each.
Root directory	224 entries	Every `.SND` and `.PGM` costs one.
Partitions	26 (A–Z)	Partitions, not SCSI IDs — SCSI only has 8.
Sounds per program	16	Slots the program format exposes.
Filenames	DOS 8.3	The disk is FAT12.

Formats

.SND is a 39-byte header followed by 12-bit linear audio at 40 kHz mono, packed two samples per three bytes. There is no sample-rate field — the machine is fixed at 40 kHz.

A = (b0 << 4) | (b1 & 0x0F)
B = (b1 >> 4) | (b2 << 4)

.PGM is 4608 bytes. Three things are easy to get wrong:

The name table starts at 0x02, not 0x24. What looks like the program's name is slot 0 — a sample like any other.
The length table at 0x0882 is not optional. Names without matching lengths leave the donor's sizes, and the MPC loads samples of the wrong length.
Unused slots must be cleared and their pads set to 0xFF, or a pad references a nameless, zero-length sample.

Full field tables, including everything still undecoded, are in the README.

Still unknown

Three u24 and two u8 fields in the SND header.
The u16 at PGM offset 0, and the block at 0x0A82.
Bytes 1–23 of each pad record — level, tuning, decay, mute group. Pads inherit the donor's settings and cannot yet be set per sample. This is the most useful thing left to decode.
Whether the MPC loads a whole partition or only a program's samples. Evidence favours the whole partition; not proven.

To work on any of these: save a program from your MPC and diff it against a generated one. A small program of four to six sounds tells you most, because a full 16-slot donor never shows what the machine does with fewer.

Download

Python 3 and numpy. Each script is standalone — save it and run it.

File	What it does
mpc60build.py	folders of WAVs → a bootable drive image
mpc60conv.py	WAV ↔ SND, 12-bit packed
mpc60drive.py	list, extract, replace and format partitions
mpc60decompile.py	take an existing image apart and label the fields
boot.bin	boot sector from a working card
donor.PGM	real program file, used as the template
header.SND	SND header layout
README.md	full field tables and the traps