A-171-4 Quad VC Slew Limiter

The A-171-4 Quad Slew Limiter is the youngest member of Doepfer’s family of polyphonic modules. What they all have in common is a four-fold layout of the functionality. All of these are influenced by common controllers and/or common control voltages. In addition, all Poly modules (at least in current production) have the option of internal … Read more

A-129 / 1 Vocoder Analysis & A-129 / 2 Vocoder Synthesis Section

The vocoder modules are no longer manufactured. The Doepfer vocoder consists – sorry, consisted – of several modules. The two basic modules A-129/1 (analysis unit) and A-129/2 (synthesis unit or filter) were only available together. In the A-129 / 1 Analysis Section, the audio input signal is routed in parallel through 13 (steep) bandpass filters, … Read more

A-111-6 Miniature Synthesizer Voice

I often used my A-111-5 as a “stopgap” when I quickly needed another simple synthesizer voice and maybe was just too lazy to patch extra VCO, VCF, VCA, ADSR and LFOs for such a secondary voice . I was often plagued by the “guilty conscience of the modularist” when I ignored the far-reaching possibilities of … Read more

A-101-3 Modular 12 Stage Vactrol Phaser

The module is no longer in production. The A-101-3 phaser has two sub-units, each with 6 phase shifters (stages): The input signal runs through the 6 phase shifters connected in series and at the output, the original and the shifted signal can be mixed as desired using a “Mix” control. The output of the 6th … Read more

A-123-2 6/12/18/24 dB Highpass

After the Curtis chip CEM3320 was no longer available, Doepfer had to stop production of the A-123 24 dB highpass filter. It’s a pity, because there were simply no other 24 dB high-pass filters on the market! In the meantime, however, a replica is available with the AS3320, so that there is now a 24 … Read more

A-123 24dB High Pass

The module is no longer in production. Of all the modules that are no longer in production for one reason or another (most often it was the unavailability of certain Curtis chips, like the CEM3320 here), the A-123 filter was probably the most difficult to replace. There were simply no other 24dB high-pass filters, neither … Read more

A-127 VC Triple Resonance Filter

The concept of the triple resonance filter A-127 reminds me personally of the resonators in the Korg PS3100, which make this polyphonic analogue dinosaur sound so special. Technically, however, the three integrated filters in the A-127 are more comparable to the SEM filter (even if they are preconfigured differently). In terms of sound, just one … Read more