Ringshifter

The Ringshifter effect combines a ring modulator with a frequency shifter effect. Both effects were popular during the 1970s, and are currently experiencing something of a renaissance.

The ring modulator modulates the amplitude of the input signal using either the internal oscillator or a side-chain signal. The frequency spectrum of the resulting effect signal equals the sum and difference of the frequency content in the two original signals. Its sound is often described as metallic or clangorous. The ring modulator was used extensively on jazz rock and fusion records in the early 1970s.

The frequency shifter moves the frequency content of the input signal by a fixed amount and, in doing so, alters the frequency relationship of the original harmonics. The resulting sounds range from sweet and spacious phasing effects to strange robotic timbres.

Note: Frequency shifting should not be confused with pitch shifting. Pitch shifting transposes the original signal, leaving its harmonic frequency relationship intact.

Getting to Know the Ringshifter Interface

The Ringshifter interface consists of six main sections.

Figure. Ringshifter window, showing different interface areas.

Setting the Ringshifter Mode

The four mode buttons determine whether the Ringshifter operates as a frequency shifter or as a ring modulator.

Figure. Mode buttons.
  • Single (Frequency Shifter) button: The frequency shifter generates a single, shifted effect signal. The oscillator Frequency control determines whether the signal is shifted up (positive value) or down (negative value).
  • Dual (Frequency Shifter) button: The frequency shifting process produces one shifted effect signal for each stereo channel—one is shifted up, the other is shifted down. The oscillator Frequency control determines the shift direction in the left versus the right channel.
  • OSC (Ring Modulator) button: The ring modulator uses the internal sine wave oscillator to modulate the input signal.
  • Side Chain (Ring Modulator) button: The ring modulator modulates the amplitude of the input signal with the audio signal assigned via the side-chain input. The sine wave oscillator is switched off, and the Frequency controls are not accessible when Side Chain mode is active.

Using the Ringshifter’s Oscillator

In both frequency shifter modes and the ring modulator OSC mode, the internal sine wave oscillator is used to modulate the amplitude of the input signal.

  • In the frequency shifter modes, the Frequency parameter controls the amount of frequency shifting (up and/or down) applied to the input signal.

  • In the ring modulator OSC mode, the Frequency parameter controls the frequency content (timbre) of the resulting effect. This timbre can range from subtle tremolo effects to clangorous metallic sounds.

    Figure. Oscillator parameters.

Following is a list of controls for the ringshifter oscillator:

  • Frequency control: Sets the frequency of the sine oscillator.
  • Lin(ear) and Exp(onential) buttons: Switch the scaling of the Frequency control:
    • Exp(onential): Exponential scaling offers extremely small increments around the 0 point, which is useful for programming slow-moving phasing and tremolo effects.
    • Lin(ear): Linear scaling resolution is even across the entire control range.
  • Env Follow slider and field: Determines the impact of incoming signal levels on the oscillator modulation depth.
  • LFO slider and field: Determines the amount of oscillator modulation by the LFO.

Using the Ringshifter’s Delay

The effect signal is routed through a delay, following the oscillator.

Figure. Delay parameters.
  • Time knob and field: Sets the delay time.
  • Sync button: Synchronizes the delay to the project tempo, in musical note values.
  • Level knob and field: Sets the level of the delay added to the ring-modulated or frequency-shifted signal. A Level value of 0 passes the effect signal directly to the output (bypass).

Modulating the Ringshifter with the Envelope Follower

The oscillator Frequency and Dry/Wet parameters can be modulated with the internal envelope follower—and the LFO (see Modulating the Ringshifter with the LFO). The oscillator frequency even allows modulation through the 0 Hz point, thus changing the oscillation direction.

The envelope follower analyzes the amplitude (volume) of the input signal and uses this to create a continuously changing control signal—a dynamic volume envelope of the input signal. This control signal can be used for modulation purposes.

Figure. Envelope Follower.
  • Power button: Turns the envelope follower on or off and enables the following parameters.
  • Sens(itivity) slider and field: Determines how responsive the envelope follower is to the input signal. At lower settings, the envelope follower reacts only to the most dominant signal peaks. At higher settings, the envelope follower tracks the signal more closely, but may react less dynamically.
  • Attack slider and field: Sets the response time of the envelope follower.
  • Decay slider and field: Controls the time it takes the envelope follower to return from a higher to a lower value.

Modulating the Ringshifter with the LFO

The oscillator Frequency and Dry/Wet parameters can be modulated with the LFO—and the envelope follower (see Modulating the Ringshifter with the Envelope Follower). The oscillator frequency even allows modulation through the 0 Hz point, thus changing the oscillation direction. The LFO produces continuous, cycled control signals.

Figure. LFO parameters.
  • Power button: Turns the LFO on or off and enables the following parameters.
  • Symmetry and Smooth sliders and fields: These controls, on either side of the waveform display, change the shape of the LFO waveform.
  • Waveform display: The LFO waveform display provides visual feedback about the waveform shape.
  • Rate knob and field: Sets the (waveform cycle) speed of the LFO.
  • Sync button: Synchronizes the LFO cycles (LFO rate) with the project tempo, using musical note values.

Controlling the Ringshifter Output Parameters

The output parameters are used to set the balance between the effect and input signals and also to set the width and feedback of the Ringshifter.

Figure. Output parameters.
  • Dry/Wet knob and field: Set the mix ratio of the dry input signal and the wet effect signal.
  • Feedback knob and field: Sets the amount of the signal that is routed back to the effect input. Feedback adds an edge to the Ringshifter sound and is useful for a variety of special effects. It produces a rich phasing sound when used in combination with a slow oscillator sweep. Comb filtering effects are created by using high Feedback settings with a short delay time (less than 10 ms). Use of longer delay times, in conjunction with high Feedback settings, creates continuously rising and falling frequency shift effects.
  • Stereo Width knob and field: Determines the breadth of the effect signal in the stereo field. Stereo Width affects only the effect signal of the Ringshifter, not the dry input signal.
  • Env Follower slider and field: Determines the amount of Dry/Wet parameter modulation by the input signal level.
  • LFO slider and field: Sets the LFO modulation depth of the Dry/Wet parameter.