Doepfer eurorack modular synthesizer fixed filter A-128

via this auction
"You have a choice of knobs. I think the smaller ones feel better, but the original knobs are here if you prefer.....

Module A-128 (Fixed Filter Bank) is a filter bank, made up of 15 parallel band pass filters, all with fixed middle frequencies and bandwidth (50 Hz / 75Hz / 110Hz / 150Hz / 220Hz / 350Hz / 500Hz / 750Hz / 1.1kHz / 1.6kHz / 2.2kHz / 3.6kHz / 5.2kHz / 7.5kHz / 11 kHz).

Each band pass filter has its own amplitude control knob, with which that frequency band can be attenuated. The bandwidth of each of the filters is approximately half an octave.

The signal at the output of the A-128 contains a mix of all the filters, depending on the position of each one's amplitude control knob.

The filter bank's main job is to emphasize individual sections of the whole audio frequency range.

This module has a maximum current draw of 20mA. Requires 20 TE/HP worth of space to fit in a Eurorack frame."