Ultra VCO

The MOTM-300 Ultra VCO represents a milestone in analog synthesizer design. Using only the finest available circuitry, the Ultra VCO has unmatched performance where it's needed most: stability and tracking. Using 4 separate temperature compensation servo loops, the average drift over 12 hours is typically 0.01% or about thirty times better than a Moog 921B VCO! Why do we call it the Ultra VCO? Because the tracking circuitry uses an ultra-matched differential pair transistor array that will hold over a minimum of 15 octaves. That's twice the range of a piano!

Although we put the focus of the design on stability, the MOTM-300 is a full-featured VCO. Sine, saw, triangle, and pulse waveforms are all available simultaneously. PWM (Pulse Width Modulation) with initial pulse width and depth creates complex spectra. Other features include:

  • Dedicated 1V/Oct input with military-spec 25ppm 0.1% summing resistor
  • 2 separate Frequency Modulation (FM) inputs, each with it's own attenuator
  • Linear FM with switchable AC or DC coupling
  • PWM (Pulse Width Modulation) from DC to over 15Khz
  • Hard and Soft sync option with Master Sync I/O jack
  • Low power consumption, only requires +/-15VDC @ 60ma
  • All audio signals wired with coaxial cable for lowest noise and crosstalk
  • Low-drift op amps and precision resistors used throughout
  • 10 volts peak-peak audio outputs
  • Frequency range from 0.2Hz to over 38Khz

The cornerstone of any synthesizer is the VCO. We feel the MOTM-300 Ultra VCO has "raised the bar" and is, quite simply, the most accurate and best-sounding analog VCO ever offered.