A-129-1/2

Vocoder Analysis+Synthesis

Note: Per Doepfer's A-129 Vocoder-Subsystem page, the A-129 series is no longer available.

The A-129 series of modules forms a modular vocoder. The basic components are an analysis section (A-129 /1) and a synthesis section (A-129 /2). As mentioned above the vocoder needs two input signals: a voice element which serves as the raw material for the tonal shaping, and is patched into the analysis section; and a carrier signal, which is patched via the instrument input into the synthesis section.

The speech signal is chopped up and analysed in the A-129/1 module, and then combined with the carrier signal in the A-129/2 synthesis section. As a result of this procedure, the carrier signal assumes the tonal character of the speech signal, but with its own pitch maintained.

Since the A-129 is a modular vocoder, and the connections between the analysis and synthesis section are external, using patch-leads, you can use this interface to patch in your choice of modules (eg. attenuator, slew limiter, CV-to-MIDI / MIDI-to-CV interfaces,, inverter, etc.). There's also the possibility of connecting the frequency bands of the analysis and synthesis sections arbitrarily, so that, for instance, a low frequency band in the speech signal can control a high frequency band in the carrier signal.

The A-129/2 synthesis section can also be used as a stand-alone voltage-controlled filter bank - or in combination with a MIDI-to-CV interface as a MIDI-controlled filter bank.

The A-129/1+2 both use 15 high quality narrow filters: 13 band pass filters, 1 low pass and 1 high pass filter.

http://www.doepfer.de/a129e.htm