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

Or listen on
New VersionXR1-E side view right
The XR1-E is an analog ring modulator with internal oscillator, preamp and LFO in a nice hand-made casing. It offers a wide variety of sounds, from the typical ring modulation and tremolo-like sounds to glissando and random-like patterns or distortion. An integrated low-noise preamp (with much headroom) allows to adapt any kind of input sources like microphones, e-guitars or electronic instruments. A bicolor LED provides optical control of the oscillator and preamp’s overdrive behaviour. The oscillator frequency is manually adjustable with two knobs for coarse and fine tuning and a has a switch for high and low (tremolo or bass) range. An envelope follower, a LFO and a Sample+Hold is provided for frequency modulation; further, there is a minijack 1V/oct. input for controlling the XR1-E’s frequency by an external CV. The envelope CV also can be optionally replaced by an external signal or a voltage from a foot pedal. The XR1-E has a footswitch input to apply an external footswitch (not included) for switching between the effect and the original (true bypass). The output level of the processed signal can be aligned by a knob on the rear. Due to the ability of battery operation the device is independent from external power supply, but there is a socket for a DC adaptor too (DC adaptor not included). The XR1-E is based on a function generator chip, which warm and smooth sound makes it excellently suitable for ring modulation and electronic music.


  • Low noise preamp
  • Bicolor LED for visual control
  • Frequency modulation with envelope follower, LFO and/or Sample+Hold
  • 1V/oct minijack input and 2nd input for external frequency control
  • Footswitch input – true bypass
  • Adjustable output gain
  • Battery (6x AA) or with external DC supply
  • Unique handmade 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: 6-8Vpp
  • Dimensions
    • 14,2 x 8,3 x11,0 cm

Video (without S+H feature):
YouTube video

  • Input/Output Sockets
    • Audio out
    • External frequency CV in (3pole, with +5V voltage source for e.g. pedal)
    • 1V/oct minijack input
    • 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)
    • AM drive (back side)
  • Switches
    • Power on/off (back side)
    • Oscillator frequency: low/high
    • Oscillator waveform: triangle/sinusoidal
    • Envelope follower: inverse modulation
    • Env./Sample+Hold mode
    • LFO waveform: triangle/square

Zickzack Ornament Sample+Hold Mode (new)

for oscillator frequency modulation:
Switch upper position
Switch ‚S+H‘ in upper position


Envelope Mode (Sample+Hold is not active)
Envelope follower
Switch middle position
Switch ‚S+H‘ in middle position


  • LFO is the Sample+Hold’s clock;
  • Envelope shape is the S+H’s analog input signal
S+H LFO Clock
Switch lower position
Switch ‚S+H‘ in lower position


  • The envelope shape – from a certain threshold – is triggering the Sample+Hold
  • The LFO’s trianglewave is the S+H’s analog input
S+H envelope clock