This is a demo of a prototype of a patchable analog synthesizer. It is based on a single voice card I have designed over the last months. Please subscribe and like and get notified about upcoming videos on my channel!

I've been so happy with the outcome of the voice card for a polyphonic synth that I've build an interface for a single card. It holds jacks for control voltages and signals, pots for all parameters, switches for filter responses, utility circuits and a power supply. It is the first time I used SMD components for all major parts.

There is a small batch of Voice Card PCBs on Tindie for sale in case you are interested and would like to support my channel: https://www.tindie.com/products/polykit/full-voice-card-for-a-polyphonic-synthesizer-pcb

GitHub: https://github.com/polykit Mastodon: https://chaos.social/@polykit

Interface Specs: • LFO with triangle/square signal • Utilities: attenuator, buffered multiple, mixer with attenuator • Power supply • Inputs/Outputs: ◦ Pitch CV 1V/oct ◦ Gate/trigger ◦ FM ◦ External input ◦ PWM CV ◦ Hard/soft sync ◦ Panning CV ◦ VCA CV ◦ Filter frequency/resonance CV ◦ ADSR output ◦ LFO output • Control pots: ◦ Mixer level ◦ Fine tuning ◦ PWM ◦ Filter frequency/resonance ◦ Panning left/right ◦ Attenuator ◦ Level input 1 ◦ Level input 2 ◦ LFO waveform ◦ LFO rate ◦ ADSR parameters • Switches: ◦ Saw/triangle signal ◦ External input ◦ Filter frequency and resonance modulation by ADSR (also inverted) ◦ Pole mixing filter mode

Voice Card Specs: • A single oscillator with saw, triangle and pulse output • Multiple VCAs to blend between different input signals, a main VCA for the envelope and a panning VCA for stereo output • An additional external input that can be mixed in, eg. a noise signal • One envelope generator for the VCA. It can also modulate filter frequency and resonance, also with an inverted signal • A pole mixing multimode filter with 8 filter responses: ◦ 4P LP ◦ 2P LP ◦ 4P HP ◦ 2P HP ◦ 4P BP ◦ 2P BP ◦ 3P AP + 1P LP ◦ 4P N • There are multiple options two switch and blend between different signals and filter responses • PWM, FM and synchronization inputs

#synthesizer #diy #analog