ATX1 is a classic all analog saw VCO core with 3 switchable modes, ART, 1V/Oct, LFO and is recommended as the basic building block for ART systems. It is designed for patching analog polyphonic synths from discrete modules or multi-mono patches in ART mode. When using ART the ATX1 takes care of the tuning including accounting for temperature changes. In 1V/Oct mode the ATX1 runs as a standard old school modular VCO. LFO mode drops the frequency range and is great for patching vibrato to other ATX1s among other things. The ATX1 outputs variable waveshapes with manual or CV control. Classic FM, PWM and hard sync are provided. A dedicated Gate Out in ART mode manages the voice envelopes or any modulation synced to that voice. We consider the ATX1 the best sounding analog VCO we ever created.