I doubt there is even a single lover of synthesizers and electronic music who never came across Jean Michel Jarre’s “Oxygene” album. And if, like me, you first heard it in a poorly illuminated room in a gloomy evening, you’ll certainly understand the shivers the oxygen sounds can bring. Like many of the 1970’s, Jarre used a lot of audio effects. In fact, and contrary to popular belief, analogue synthesizers were (almost) always recorded with effects back in the 1970’s. And one of the most beloved effects of the 1970’s was the phaser.
Just a little recap about what a phaser is: A phaser is a circuit were the incoming sound is split over a number of all-pass filters (in parallel). Why an all-pass filter, you ask? And how can an all pass filter bear an effect? Well: when the audio signal goes through a filter, it delays a little bit. Moreover, this delay is more noticeable over certain frequencies (the maths of it is quite interesting, but unnecessary here). So when the sound that when through the different filters is mixed together it will have phasing distortion (the crests and valleys of each part od the signal are not in phase with each other anymore). This provides feedback and cancellation to several areas od the spectrum. Using an LFO to modulate the “cutoff” of the all-pass filters allows for this effect to vary over time.
Phasers are a legal requirement if you intent to use a vintage string machine like the Arp Solina or the Eminent. You may face persecution by the Hage courts if you fail to ensure your string machine is properly phased. :P Back in the 1970’s, one of the best phasers around was the Bad Stone by Electro Harmonicx. They are so great, they are still being produced by EHX and you can buy them on amazon or amazon (UK).
This Behringer pedal is a clone of the EHX Bad Stone and Small Stone pedals. It is a very simple 4-stage (4 all pass filters) monophonic phaser, with positive and negative feedback (set by the TONE knob) and variable filter sweep LFO. The LFO rate goes from 6 seconds (0.16 Hz) to about 0.06 seconds (approximately 17Hz), but if you want to sync the LFO to the tempo, you’ll probably have to do it the old way: by ear! This is not a deal breaker for me: there are lots of tempo sync’ed effects to go around. What this pedal excels at is to provide you with that warm phaser tone that is so characteristic of the old days. In fact, I might even buy a second unit for myself in order to explore the world of stereo phasing.
The build quality is pretty decent: it is a large metal case (not very heavy) with a nice stomp switch, and a positive fell on the rate knob. I don’t know if Behringer is still making these pedals, but they can still be found on amazon and amazon (UK) for a very decent price (about 20 to 25 euro, or equivalent). In my opinion, if you want that vintage phaser vibe going on, you should add one to your arsenal (unless, of course, you already own one of the EHX phasers).