The Frequency Shifter is a small, innocuous looking device from the standard Ableton Live Library. It's easily overlooked but can be a powerhouse when it comes to sound design.

Frequency Shift vs. Pitch Shift

Often confused, and similar in nature, it's worth knowing the difference between Pitch Shifting and Frequency Shifting.

Pitch Shifting: Shifts the incoming signal by musical intervals. This is done by multiplying or dividing all the frequencies within the signal. To pitch shift a signal by +1 octave, we multiply each frequency by two, thereby preserving the harmonic relationships within the signal. Pitch shifting is the classic sound of speeding up or slowing down a tape, or playing a sample away from its root note in a sampler.

Frequency Shifting: Again, this involves changing the frequency content of a signal, but in a very different way. Frequency Shifting works by moving each frequency in a signal by a set amount. For example +1000 Hz. Every frequency within the signal is shifted by the same amount and this means that the harmonic relationships within the signal are broken, resulting in a very different sound. Some describe the sound as metallic or similar to ring modulation.

The Frequency Shifter is a great sound design tool.

The Frequency Shifter device is super simple. There are Coarse and Fine knobs to set the amount of frequency shift. There's a toggle button to change from pitch shifting to ring modulation and a '˜Wide' button to create a stereo effect by inverting the Spread value in one channel so that one channel is shifted up, whilst the other is shifted down. There is also a Drive button which enables a distortion effect, although this is only available in Ring Modulation mode.

On the left side of the interface are the LFO controls. There are six possible waveform shapes, and the amount of modulation applied to the Frequency shifting is controlled by the Amount knob. Rate controls the LFO speed and it can be synced to host tempo. Finally, stereo effects can be created by using the Phase and Spin controls. Phase changes the phase between the LFOs used for the left and right channels and Spin offsets the LFO speed for each channel.

So what can I do with it?

• Phasing/chorus effects: Used in small amounts, Frequency Shifting can create wonderful phasing/chorus effects. On guitar, electric piano or anything you'd normally use a chorus on, try a shift of a few Hz (just using the fine control) with the Wet/Dry knob set to 50%. Try experimenting with the LFO to create more traditional chorus effects. 
  
• Alien/Robot Voices: Try shifting a vocal by around +/- 500 Hz. Use Wet/Dry to taste. 
  
• Tuning Drums: Used in small amounts, frequency shifting can make a nice alternative to pitch shifting when tuning drums. Use in the range of +/- 100 Hz the results will still sound natural. Leave the Wet/Dry control at 100%.
  
• Frequency Shifting Delays: Make your own frequency shifting delays by placing a Frequency Shifter after a Delay device on a Return Track. Set the Delay's feedback to 0% and use Live's own feedback routing to send the Return Track back to itself. You'll need to enable the Send on the Return track manually as Live disables them to prevent feedback disasters.

In order to allow Live to create a feedback loop by sending a Return Track signal to itself, you must first enable the Send.

The Frequency Shift device is a fantastic part of the Ableton Live library. Whenever I need a chorus or phaser effect, I often reach for the Frequency Shifter first. And for alien, sci-fi and sound design applications, it's invaluable. All hail the Frequency Shift!