Dual VCO

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The Circuit Slices Dual Parallel VCO combines two oscillators in one narrow module for Eurorack-compatible synthesizers. The 12HP width makes it smaller than most single VCOs. It is pre-patched, or normalled with the VCOs controlled in parallel; the FREQ knob controls both VCOs while there are two independent fine-tune controls (FINE 1 and FINE 2). This allows overall pitch adjustment while retaining an interesting interval or modulation effect between the two VCOs. You may also supply separate pitch control voltages to each VCO individually, but the PWM and FM inputs always go to both VCOs. The VCOs are high quality, matched-transistor, temperature-compensated type with triangle, sawtooth and pulse outputs. It makes cool thick sounds for just one narrow module. 

Specifications for the Dual Parallel VCO, part number CS023

• Eurorack format
• Standard one-volt-per-octave pitch control
• Over 10V control range
• Frequency range for VCO 1 and VCO 2: less than 10Hz to over 15KHz
• Typical pitch tracking errors for 10 octaves: · 0% error for first 4 octaves· Less than 1% error for next 4 octaves · Less than 2% error up to the 10th octave
• Outputs: Sawtooth, Triangle, Pulse 
• Output levels: 10Vp-p (+/- 5V)
• Power: +12VDC @ 52mA, -12DC @ 52mA
• 12 HP, Depth from front panel: 1.55”

• Features for the Dual Parallel VCO, part number CS023
• Narrow width
• Incredibly fat sounds for one small module
• Modern SMT design for small footprint and decreased cost
• High quality VCOs
• Matched-transistor pair oscillator design (triangular-type core)
• VCO cores use high-performance, low noise, zero drift, op-amps (OPA series or similar)
• Each VCO is temperature-compensated (TEMPCO) for frequency stability
• Oscillators track up to 10 octaves
  
   

Six inputs: 

· 1V / octave 1 for VCO 1

· 1V / octave 2 for VCO 2*

· FM 1, 2 frequency modulation for both VCOs

· PWM 1, 2 pulse with modulation for both VCOs

· Sync 1

· Sync 2

*Note that a signal or CV patched to VCO 2 is “Normalled” with VCO 1

CV patched into “1V / oct 2” only, controls both VCOs

CV patched into “1V / oct 1” separates the two VCOs into independently controllable oscillators

Six outputs: 

· 2 Triangle, 

· 2 Sawtooth, 

· 2 Pulse

(Outputs can be passively summed using “stackable” cables or a passive “multiple”)

Controls:

· FREQ knob controls course pitch for both VCOs 

· FINE 1 and TUNE 2 knobs fine-tune the VCO pitch separation over two octaves

(Adjust FINE controls for a given interval and it tracks as the FREQ control is adjusted)

· PULSE WIDTH knob controls the initial pulse width of the pulse output

· PWM knob controls the amount of pulse width modulation applied to both VCOs

· FM knob controls the amount of modulation (lin or exp) to both VCOs

· VCO 2 RANGE switch lowers the range of VCO 2 for greater separation between the two oscillators

· FM MODE switch selects between Linear and Exponential frequency modulation

List price $152