Vocorder

Analog Spectral Vocoder/Looper

The Flame “Vocorder” module is a compact combination of an analog vocoder and a digital CV recorder (looper). The centerpiece is an 8-channel analog vocoder with a total of 16 analog bandpass filters for analysis and synthesis.

The analog generated analysis envelope CVs are digitized and output via the DA converter to the analog VCAs of the synthesis tapes. With the help of the record function, the envelope CVs of the analysis channels can also be recorded digitally and played back in the loop. You can manipulate the playback in different ways: swap filter channels on the fly (rerouting), change speed and playback direction etc.

The module can also be a “normal classic vocoder”: the envelopes are then always looped through via AD / DA conversion (direct vocoding) and can of course also be recorded. The analysis unit is ineffective during playback because the envelopes are played back from the memory. The current version is very compact, the module is only 12HP wide – see photo.

There are two audio inputs for analysis (voices, drum etc) and synthesis (instruments). A monophonic digital oscillator with three waveforms and an analog noise generator are available for internal synthesis. There is also an unvoiced / voiced switch (controls the highpass with noise when there is sibilance). A respective mix controller is responsible for both synthesis sources. The VCO has a 1V / oct input and an additional direct audio output. The synthesis filters have audio outputs for odd / mono and even (mix of even / odd channels).

The looper recorder has the following functions: buttons for record, start, stop. A triple toggle switch for the playback direction forwards, backwards, ping-pong, another for the type of triggering: Loop, OneShot, Gated. You can record about up to three minutes. The playback speed is adjustable (also via CV). The sampled loop is retained in the battery-backed memory even after switching off.

In addition, there is a controller for rerouting the filter channel assignments from the analysis (or recorded channel) to the synthesis filters, also accessible via CV. A freeze function is also available.

The filter / cutoff control regulates the synthesis bands manually with a combined lowpass-bandpass-highpass algorithm, so the synthesis filters can also be used as simple audio filters.