ADDAC 601 VC Filterbank

The ADDAC 601 module is an analog fixed filter bank with eight frequency bands. Each band features voltage control of amplitude and a separate envelope follower. A number of audio outputs and many possibilities make this filter bank a superior unit.

The 601 VC Filterbank has two audio inputs, the first one accepts line level and has an attenuator. The second input has modular synth level and is not controllable.

The audio signal is being divided into eight frequency bands, with center frequencies at 50 Hz / 110Hz / 220Hz / 500Hz / 1.1kHz / 2.2kHz / 5.2kHz / 11 kHz. Each band´s amplitude can be set with a control or can be voltage controlled by high-quality VCAs (bipolar CV, /- 5V) and is displayed with a LED. If a cabls is inserted into the amplitude CV jack then the level control acts as a combined bias control and attenuator. The amplitudes affect all outputs.

Eight switches act as killswitches and remove the corresponding frequency band from the main mix. The odd and even outputs (see below) are not affected by the switches.

Each frequency band has an individual output (post VCA) and an envelope follower output that will display the momentary amplitude as a CV (0-10V). The ODD and EVEN sockets output only the signals of the even frequency bands and the odd frequency bands. Might be pretty interesting when you spread those in the panorama. Furthermore there are two main outputs, one is 100% wet the other has a controllable dry/wet mix.

Cross-patching the envelope follower outputs to the amplitude CV inputs might be funny, as well as feeding the even/odd outs back to the second audio input ^^.