Tracking with the Mutronics Mutator

The Mutator is a dual mono/stereo rack effects unit, boasting an amplitude follower with external key input, LFO and a VCF/VCA courtesy of an SSM 2045 on each channel. You can hear one squeaking and screeching over Johnny Greenwood's guitar at the end of Radiohead's "Paranoid Android." The filter is of the four pole, 24 db/octave lowpass flavor made famous by Dr. Robert Moog, but the 2045 also has a two pole, 12 db/octave lowpass that Mutronics elected not to use. We asked Tony Allgood of Oakley Sound Systems in the UK to tap the IC's two pole output and include a two/four pole toggle switch for each channel, and recently tracked a few sources through it at the Bridge.

First, we tracked a drum loop from Reason:

• Dry loop
• 12 db/octave, slow LFO sweeps
• 24 db/octave, slow LFO sweeps

Then, we tracked sustained chords from Reason's "Maelstrom" synth, with its filters bypassed.

• Maelstrom chords, dry
• Maelstrom chords, 12 db/octave, slow LFO sweeps
• Maelstrom chords, 24 db/octave, slow LFO sweeps

Finally, we convinced Owen to bust out his beautiful old bass and lay some stank down. The bass was tracked into Pro Tools through a Universal Audio 2-610 DI/pre. The first passes used the Mutator's amplitude follower to create an auto-wah/envelope filter effect:

• Electric bass, 12 db/octave autowah
• Electric bass, 24 db/octave autowah

The second passes used the Mutator's key input to trigger the envelope. We reused the dry drums and offset them by a quarter note for this effect:

• Electric bass, 12 db/octave keyed
• Electric bass, 24 db/octave keyed

This isn't Gearslutz, so we weren't especially concerned about matching volumes for comparison. The bright, fizzy character of the two pole filter, made famous by ARP and Oberheim in the 1970s, is apparent at any level. It can be a subtle difference, depending on the program material and filter settings, but it's a euphonic one, and both modes will likely see use at the Bridge.