Overview
The A-112 is a 10HP module in Doepfer’s A-100 system that combines a voltage-controlled 8-bit sampler with a wavetable oscillator. Doepfer pitches it as a source of the grungy sound of early 8-bit samplers, not a rival to modern samplers. It has 128 KB of memory in two banks, S1 and S2, of 64 KB each, which is about 2 seconds per bank at a 32 kHz sampling rate. Sampling time ranges from about 1 second at 60 kHz to 30 seconds at 2 kHz. Memory is kept after power-off by a rechargeable battery, which Doepfer says should be checked at least every two years.
Three switches set the mode: sample playback, recording, looping, MIDI dumps, and effects like delay, reverse delay and pitch shifting with freeze. The Tune control and a 1 V/oct CV input set the sampling rate, which is also the pitch on playback. Doepfer lists the A-112 as no longer a standard product.
Wavetables on the A-112 Sampler / Wavetable Oscillator
In wavetable mode, a 64 KB bank is read as 256 pages of 256 bytes, so each page is one 256-sample, 8-bit wave. The audio input turns into a second CV input that picks the page, and moving it sweeps through the tables. Any sample can be scanned this way, but for a classic wavetable sound the memory has to hold proper single-cycle tables. Doepfer suggests its A-183-2 offset and attenuator module to set the starting table and the sweep depth, driven by an LFO, an envelope, random voltage or a controller such as a ribbon or joystick.
Doepfer says those tables are normally made on a computer and sent to the A-112 by MIDI dump: a SysEx transfer of a whole bank, or of a single 256-byte page in wave dump mode. The module can also record into one page at a time from its audio input: in wave record mode, a high gate samples the input into the selected 256-byte page, looping over it until the gate goes low. Doepfer offered a DOS program, SAMPLEDUMPLOADER, to move A-112 samples to and from WAV files over MIDI SysEx, noted as running under DOS 5.0 and later and only partly under Windows 95.
WaveStack can’t write any of this. It has no MIDI dump export, and its Other tools target writes 16, 24 or 32-bit WAVs, not 8-bit. You could export a 256-frame table of 256-sample frames with Other tools, convert it to 8-bit in an audio editor, and try Doepfer’s loader on an old machine, but Doepfer doesn’t document which WAV formats the loader accepts, and we haven’t tested it.
A more practical route uses the module’s own wave record mode: play a table into the audio input and record it, page by page, at a sampling rate that fits one cycle into 256 samples.
Specifications
| Resolution | 8-bit |
|---|---|
| Memory | 2 banks (S1, S2) of 64 KB |
| Wavetables per bank | 256 pages |
| Samples per wave | 256 (one byte each) |
| Transfer | MIDI SysEx dump (bank or single wave) |
| Width | 10HP |
Frequently asked questions
How do I load wavetables into the Doepfer A-112?
By MIDI dump. Doepfer’s manual says wavetables are normally made on a computer and transferred as a SysEx dump into bank S1 or S2, either a whole 64 KB bank or a single 256-byte wave in wave dump mode. Doepfer also offered a DOS program, SAMPLEDUMPLOADER, to convert between A-112 dumps and WAV files. The module can also record waves itself through its audio input in wave record mode.
Can WaveStack export for the A-112?
Not directly. The A-112 takes 8-bit data over MIDI SysEx, and WaveStack has no MIDI dump export or 8-bit output. Its Other tools target can write a 256-frame table of 256-sample frames at 16-bit, which you’d then need to convert to 8-bit and send with Doepfer’s DOS-era loader. Doepfer doesn’t document what that loader accepts, so treat it as an experiment.
How is A-112 memory organized for wavetables?
Each bank is 64 KB. In wavetable mode that becomes 256 pages of 256 bytes, and each page is one wave of 256 eight-bit samples. A CV at the audio/Wave CV input chooses the page, so sweeping that voltage steps through the tables. Doepfer’s manual notes that at a 32 kHz sampling rate each page lasts 8 milliseconds, which limits how fast you can sweep without skipping pages.
Will the A-112 lose its wavetables when powered off?
Not right away. The memory is non-volatile, kept alive by a rechargeable battery. Doepfer says batteries have a limited lifespan and should be inspected at least every two years, so an older module with a tired battery can lose its contents. Keeping a MIDI dump of each bank on a computer is the backup the module was built around, and Doepfer’s FAQ has details on battery lifespan.