CG Products
design — construction — sound


Ring Modulation Oscillator



Input: Metallophone


Input: E-Guitar


Input: Microphone (Trumpet)


Input: E-Piano


Input: Rhythm machine; with different settings of the switch ‚Sample+Hold‘ and LFO


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XR1-E side view right

The XR1-E is a ring modulator with fixed internal modulation oscillator. The included low-noise preamp makes it specially suitable for instrument pickups or microphones; sensitivity of the preamp is adjustable from line-out to microphone levels.
The oscillator’s working frequency is contollable by two knobs for coarse and fine tuning. In addition, there are two special options to modulate the oscillator’s frequency: Once by the internal LFO and second by an envelope follower, which varies the frequency dependent from the instrument input’s signal amplitude. The socket „Frequency CV in“ on the back side provides the ability to modulate the frequency by an external control voltage or by e.g. a foot pedal.
The XR1-E is battery operative and independent from external power supply; but if required, there is a DC jack on the back for using an external DC power adaptor.
On the input jack „Footswitch“ an external footwitch may be connected to switch between ‚dry‘ and ‚wet‘. In the ‚dry‘ mode, the XR1-E offers true bypass functionality.
Heart of the XR1-E is an ancient function generator chip with amplitude modulation input. Its warm and brillant sound makes it excellently suitable for electronic music. Amplitude modulation results, with lower oscillator frequencies, in tremolo-like sounds; if the oscillator frequency is higher or almost the same as the input signal, the results are strange harmonies and disharmonies due to the fact that a ring modulator generates additional frequencies like summation and difference tones.


  • For instrument or microphone
  • Low noise preamp
  • Coarse and fine frequency tuning
  • Envelope follower and LFO for frequency modulation
  • External frequency control by pedal or CV (1V/oct adjustable)
  • Footswitch input (true bypass)
  • Battery operative (battery lifetime ≈7-10h)
  • Handmade steel casing

PDF documentation


XR1-E front view XR1-E side view left XR1-E top view XR1-E side view right XR1-E back side view XR1-E bottom view

Zickzack Ornament

  • Power Supply
    • 6x AA Mignon cells or
    • External power adaptor 6-15V, 100mA (not included)
  • Oscillator Frequency
    • Hi: ≈ 8Hz – 18oooHz
    • Lo: ≈ 0,2 Hz – 60Hz
  • Instrument Input
    • Impedance: ≈380kΩ
    • Max. input voltage: 3,5Vpp
  • Dimensions
    • 14,2 x 8,3 x11,0 cm

YouTube video
  • Input/Output Sockets
    • Audio out
    • External frequency CV in (3pole, with +5V voltage source for e.g. pedal)
    • External DC in – 2,1mm DC jack
    • Instrument signal in
    • Footswitch in
  • Potentiometers
    • Oscillator frequency
    • Oscillator frequency fine tuning
    • Preamp gain
    • Carrier (oscillator tone) surpression
    • Bypass (signal to effect ratio)
    • Envelope follower/ext. CV modulation depth
    • LFO frequency
    • LFO modulation depth
    • Output gain (back side)
  • Switches
    • Power on/off (back side)
    • Oscillator frequency: low/high
    • Oscillator waveform: triangle/sinusoidal
    • Envelope follower: inverse modulation
    • LFO waveform: triangle/square