Commodore Sound Expander

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Commodore Sound Expander
Type:	Cartridge
Producer:	Commodore/Music Sales Limited
Price:	125 US$; 99.99 £; 399 DM (ca. 200 €)
Released:	1985
Discontinued:	1986
Processor:	Yamaha YM3526 OPL
Memory:
OS:
Info:	External Software "F.M. Sound Expander" with C64, SFX or MIDI keyboards

The Commodore Sound Expander or SFX Sound Expander is a sound synthesizer cartridge with 9 voices for the Commodore 64. It was developed by Richard Watts. The synthesizer chip is a Yamaha YM3526 OPL, which can upgraded by a YM3812 OPL2 chip, which is also used by AdLib- and Soundblaster sound cards in PCs. This cartridge was produced by Music Sales Limited in the UK and marketed as "Commodore SFX series" by Commodore world-wide.

Installation

Commodore cartridges: SFX Sound Sampler, Magic Voice (Speech Module) and Sound Expander (FM Sound Module).

The cartridge is plugged in into the expansion port of a powerlesss C64. The audio plug can be plugged in into speakers or devices which have a speaker plug in. Also can added the external SFX keyboard with 61 keays and 5 octaves

Manual

A manual (user's guide) exists, but provides very little technical information. And also the audio lead book "Start Playing Keyboard - The SFX-Tutor" by Peter Lavender.

Programming

TBD.

Construction

• Used Chips:
  • Yamaha YM3526 OPL
• ROM : ?
• RAM : ?
• Dimensions: 53 × 140 × 135 mm
• Weight: 315? g
• Power Supply: 5 V= through C64 expansions port
• Power: ca. ?? W
• Ports:
  • Expansions port for connection other cartridges
  • Cinch for audio out
  • SFX interface for connection a external SFX keyboard.
• Extras:
  • Chinch cable
  • Software "F.M. Sound Expander" (aka "Riff Machine") by Music Sales Ltd. on datasette or disk.
  • Manual in or
  • Songbook by Peter Lavender: "Start Playing Keyboard - The SFX-Tutor" (Music Sales)
  • Keyboard stickers
• Optional extras:
  • Plastic overlay keyboard for using on C64 keyboard
  • Commodore SFX keyboard with 61 keys and 5 octaves
  • MID interface for other MIDI keyboards
  • Software: "FM Composer and Sound Editor" (2 programs with manual)
  • Other songbooks avaiable

Technical Details

Reverse engineered schematic (SVG)

FM-Software

• Original software: "F.M. Sound Expander" (aka amazing "Riff Machine") on tape or floppy disk.
• CSDb - Release No. 119462
• CSDb - Release No. 119462 C64 DRO player by Gábor Lénárt
  • https://github.com/lgblgblgb/c64-sfx-cartridge-player/wiki
• CSDb - Release No. 147615 FM-Sid by "4-Mat"
  • VGM-Player by "4-Mat"
• CSDb - Release No. 157163 Vibrants FM by "Xentax"
• 12 voice demo 2 stereo GoatTracker songs

Clones

Clone without external keyboard connection.

Since 2016 exists a "Sound Expander clone" by Krzysztof Iwanowski, which can bought for 25 Euro.

FM-YAM sound expansion with OPL2

Xentax released FM-YAM in March 2018. FM-YAM is a Sound Expander compatible with ym3812 (OPL2), audio in (to mix SID audio) and audio out (with FM and SID mixed). Over 200 cartridges have been sold to date. See MsMadLemon's review here: https://www.youtube.com/watch?v=Q32I0jk7THE. It also featured in the Zzap!64 Annual 2019.

Links

Wikipedia: Yamaha_YM3526

Wikipedia: Yamaha_YM3812

• Some photographs at 8bit.dk
• Nice article about the SFX series of modules and software at floodgap.com
• Sound Expander schematics at zimmers.net

Videos

• youtube.com Infos
• youtube.com Software "F.M. Sound Expander"
• youtube.com Software "F.M. Sound Editor Composer"