XR1-E Ring Mod Pedal

CG Products XR1-E

The XR1-E from CG Products is a fully featured ring modulation pedal, capable of a huge palette of sounds and a medley of modulation options. Best known for helping to create the distinctive voices of the Daleks on Dr. Who, ring modulation colors, morphs, and imparts the spectral characteristics of one signal on another through voltage multiplication. Voltage multiplication modifies the amplitude of one signal (the Carrier) with another (the Modulator). The Carrier is the signal present at the Instrument input jack, and the XR1-E's internal VCO acts as the Modulator. This wide range VCO includes two frequency modes, running from sub-audio to above the hearing range of most people, creating everything from tremolo to ultra-high frequency sidebands. The fine tune knob offsets the coarse frequency over a smaller range, letting you dial in the perfect frequency relationship between modulator and carrier. The VCO includes two waveforms, triangle and sine. Sine waves are traditionally used for ring modulation and they don't include any harmonics apart from the fundamental frequency. The triangle waveform's additional harmonics increase the timbral complexity of the ring modulation. While the coarse and fine tune knobs provide manual control over the modulator's frequency, the XR1-E also includes a multitude of methods to modulate the modulator. The triangle/square wave LFO features a frequency range that goes from less than one cycle per second into audio rate.

The other primary front panel modulation combines an envelope follower and sample and hold with three modes of operation. This section features an attenuator to adjust the level of modulation, and a polarity switch that sets if the modulation increases or decreases the frequency of the VCO. The top mode bypasses the sample and hold and instead uses the envelope follower or external frequency CV inputs. An envelope follower creates a voltage based on the volume of an input signal. Large volume spikes or abrupt changes in level change the frequency in more extreme ways compared to smaller fluctuations. This mode excels when used with input signals with sharp transients, such as drums. A sample and hold captures the level of a voltage every time it receives a timing signal, creating stepped modulation based on the relationship between the two. While a sample and hold is most frequently used with white noise, the XR1-E utilizes other voltage sources. With the switch in the lower position, the envelope follower acts as a clock signal and the LFO's triangle wave is sampled. In the center, the envelope follower is sampled using the LFO's square wave or the external clock input jack. The Frequency CV in jack overrides the envelope follower, allowing you to use any other signal in place of it. A dedicated 1V/Oct input jack allows you to sequence the pitch of the oscillator, particularly useful when sequenced in conjunction with the audio at the carrier input. The Bypass knob blends from the dry input signal to the pure ring modulated output, while the footswitch jack provides a dedicated on/off bypass control by way of an external pedal. The Carrier Suppression Control reduces the level of the carrier and outputs more of the modulator, providing unusual timbres not found on most ring modulators. It runs either off of six AA batteries or can be used with an external center negative DC power supply with an input voltage range of 6-15V. The XR1-E's collection of features sets it apart in the world of ring modulation, providing a plethora of timbre shaping tools that creates simply out of this world sounds.

XR1-E Features

• Ring modulation pedal
• Internal sine/triangle VCO that goes from sub-audio to ultra-sonic frequencies
• Complex modulation options work in conjunction to provide automated timbral shifts
• Envelope follower changes the VCO pitch based on volume
• Wide range triangle/square wave LFO
• Sample and hold with switchable and patchable input sources
• 1V/oct CV input
• Carrier suppression and bypass knobs blend between the dry input, ring modulated output, and internal VCO
• Low-noise preamp with adjustable gain
• Bypass footswitch jack for true bypass