RC Filtering for SSM2164 CVs fed from DACs

Posted by & filed under Filters, Synth DIY, VCAs + Amplifiers.

I typically use the 12-bit MCP4822 DAC to produce a CV for the SSM2164 (or CoolAudio V2164, it’s the same thing) . This is a good, cheap combination. However, the 4822 produces an output of 0-4.095V, whereas the 2164 needs 0-3.3V. It is possible to use a simple voltage divider to reduce the voltage to the correct level, and it is also possible to add a capacitor to give an RC 6dB/Oct rolloff whilst we’re doing it. However, it’s not… Read more »

Single VCA crossfader

Posted by & filed under Projects, Synth DIY, VCAs + Amplifiers.

There are a number of situations where it is useful to be able to crossfade between two different signals with a single control. Examples might be a wet/dry control on a delay effect, or a waveform knob on an oscillator that goes from ramp to square continuously. The simple and obvious way to do this is with a dual-gang pot. Each gang controls one signal, and it’s easy to wire so that as one increases in level, the other decreases,… Read more »