The new Tremolo from MXR has stereo capability for stage-filling swampiness. Review by Huw Price
The M-159 Tremolo is basically a Dunlop TS-1 in a smaller, pedalboard-friendly chassis. The power supply arrangements aren’t quite so friendly: you’ll need two 9v batteries or an 18v supply. Like the Carbon Copy it’s finished with metallic enamel, plus classy metal T-type knobs.
Controls include the usual Depth and Speed, plus a Shape control. Counterclockwise, the waveform that modulates the volume is a sine wave; this transforms into a trapezoid wave in the centre, and a square wave fully clockwise. It won’t change the sound, particularly at high Speed settings, but it does change the feel.
Stereo in/stereo out tremolo pedals are rare. Stereo out might be useful for running two amps, but it’s hard to see the full benefit of a stereo input. Maybe it could be placed after a stereo effect on your pedalboard (or maybe your keyboard player will like the idea, and steal it). Conveniently you can use TRS cables for the stereo input and output, but this pedal works in mono too.
There’s a second footswitch labelled Pan. In default mode the modulation from both outputs is in sync, but when you activate Pan the modulation ping-pongs between the outputs with an LED that flashes alternately red and green.
There are no nasty noises and everything works smoothly. The Speed control is well designed, taking you from lazy undulating swells to a rapid blurry stutter. It’s hard to imagine needing anything faster or slower, so top marks. Similarly the Depth control genuinely goes from off to on, and you can really hone in on the perfect balance.
The Shape control is really about feel more than sound, and for a Fender amp-style trem I’d probably keep it at or near the centre position. Some Vox amp trems have more of a square wave feel, but this box can handle all that too. There’s no right or wrong with tremolo – just use your ears and understand that you might need to alter the waveform shape depending on your speed setting.
Splitting the stereo output into two amps creates a glorious, room-filling effect that’ll keep you playing for hours. There’s nothing gimmicky about it, and it would be superb for recording (but be warned: the outputs aren’t isolated from each other, so you’ll get the usual two amp earth loop problems. Since we’d never, ever recommend lifting the earth on one amp to cure it, a safer solution will have to be found if you want to record with this setup). Our other issue with the M-159 is the way it slightly drops the volume of your guitar signal and thins it out, but this is a common problem with tremolo pedals.
With the Carbon Copy, MXR has managed to add versatility and minimise noise without sacrificing the ever-popular tonal qualities of BBDs. As with the vintage echo devices it seeks to emulate, your opinion of it will depend on whether you like the way it colours your sound. The Tremolo is also versatile but the volume drop and the lack of provision for earth loops might bother you. As a mono trem it's impossible to say that it sounds better than cheaper alternatives like the Demeter Tremulator or the Carl Martin Surf Trem - but if you need stereo, then there aren't that many alternatives.