Kilpatrick Audio K3021 Master VCO Eurorack Module

Built on the success of K3020 Dual VCO, Kilpatrick Audio K3021 Master VCO offers a single-channel oscillator based on this famous design. Completely redesigned to replace now hard-to-find parts, K3021 uses a completely new triangle core design based around discrete transistors for an amazing tone and excellent stability. Useful as both your main pitch oscillator and as a complex low frequency signal source (LFO), K3021 Master VCO is a workhorse module great for any system.

One of the features that makes K3021 extra special is its use of complex waveshapers and pulse width modulation circuits to create unique timbres. You can select among sine, triangle and ramp waveforms for the WAVE section. These waves then feed into the triple pulse width modulator to create very rich pulse waves that have a much more lively character than a simple single-channel PWM. Choose from one of three PULSE output combinations for unique variations.

The BLEND and PULSE outputs can be used independently or can be combined through the use of the ultra-low distortion blend section. Smoothly fade between the WAVE and PULSE waveforms either manually or with voltage control. By using the blend circuit especially with the LFO mode engaged, very complex modulation waveforms can be easily created.

• Features
• Master VCO with onboard precision power regulation
• LED indication of selected switch positions and VCO core activity
• 1V/octave CV input, factory trimmed for 1V/octave response
• Linear FM input with level control
• Fine and coarse tuning controls
• Normal VCO frequency range: 2Hz to 15kHz
• LFO mode switch with period ranging from ±60 seconds to low audio rate
• Temperature-compensated exponential converter with matched transistors
• All-new discrete triangle core and sine wave shaper
• Wave shaper with switch-selectable sine, triangle or ramp waveforms
• Pulse shaper with triple pulse width modulators for complete timbres
• Voltage-controlled mixing between wave and pulse waveforms
• High-end blend VCAs with ultra-low distortion and linear control
• Sync input for hard syncing of VCO core
• PWM input with level and offset controls
• Blend VCA control input with level and offset controls – full deflection with 5Vpk-pk
• Blend output from the blend VCA containing wave and/or pulse waveforms
• Pulse output from the pulse shaper containing pulse waveform
• All inputs and outputs are tolerant of +/-12V
• All outputs drive 10Vp-p with 1K output impedance
• Designed and made in Canada using high quality parts
• Physical specifications
• Size: 18hp
• Power usage: 90mA @ +12V, 50mA @ -12V