A drumkit by the British company Cheetah.
The drumkit was able to play 8bit sound samples.
Quality of the playback was nice, considering the time and price.
The samples was read from the suplied tapes.
There was serveral tapes with different themes!.
Along with the Amdrum came a sequencing program.
It was possible to copy the samples to disc, but the sequencing program had to be patched!
Amdrum was probably Cheetahs version of the SpecDrum (As revealed on the PCB "AMSTRAD SPECDRUM")
No CPC emulator supports the Amdrum. To hear 'Amdrum' in action the Spectrum emulator Spectaculator emulates the SpecDrum.
No other software than Cheetahs own sequencer is know to use the Amdrum.
Technical Specifications
The PCB(oneside) contains five chips:
74LS30N | Single 8-input NAND | Port decoding, /ADDR_MATCH=LOW when A8..A15 all HIGH |
74LS32N | Quad 2-input OR | Port decoding, /DAC_WRITE when /ADDR_MATCH, /IORQ, /WR all LOW |
SN74LS04N | Hex Inverters | purpose unknown? (used in the analog part, not for Port decoding) |
TL064CDP | Quad Amplifier | no info how the 4 amplifier stages are used? |
Ferranti ZN428E-8 | 8bit DAC | mono one-channel 8bit D/A converter (unsigned samples) |
The Amdrum probably uses port #FF50 I/O, needs to be confirmed though.
- ZN428 Datasheet - 8bit D/A Converter
- TL064 Datasheet - Quad Amplifier
Kits
Afro Kit Covertape
Electro Kit Covertape
Latin Kit Covertape
Tapes
Amdrum Tape
Afro Kit Tape
Electro Kit Tape
Latin Kit Tape
Pictures
Manual
- Amdrum Manual (pdf)
Reviews / Commercials
Review of the Amdrum in Amstrad Computer User
Weblinks
Other playback devices
- Digiblaster (DIY) (8bit DAC on printer port)
- Music Machine
Videos
A presentation(from around 1985) of the ZX Spectrum version of the Amdrum(Specdrum), also mention of the upcomming Amstrad CPC version
{{#ev:youtube|m6R_W9CZWGU|200}}
Download
- Amdrum.zip (CDT for Emulators)
- Amdrum Afro Kit.zip (CDT for Emulators)
- Amdrum Electro Kit.zip (CDT for Emulators)
- Amdrum Latin Kit.zip (CDT for Emulators)