Phase Shifter VSTi
In the late 60′s composer Steve Reich stumbled across a technique he called phasing, which was to have two identical tape loops that run at slightly different speeds, the result is that every possible combination of sound is cycled through until they arrive back in sync. The result with a melodic piece of music is that it moves through moments of chaos and moments of melody. Brian Eno also used this technique extensively on some of his Ambient albums. After becoming interested in this in 2008, I decided to build myself a simple plugin to emulate the process as it was surprisingly difficult to emulate with any software I had at that time. I have now expanded it to emulate four tape decks and many moreÂ features such as time stretching, filters & FX so that it has become a much more capable synthesizer.
Phase Shifter is designed more for playing live, though full VST automation is supported and having an external controller makes the process a much more rewarding experience. It also has a built in recorder so that the output can be recorded directly to disk. It works by loading up to 2 WAVs, and is triggered via a midi keyboard. MiddleÂ C will play the WAV at it’s original speed. It has a lot of potential for producing interesting sounds, I would be pleased to hear of the different ways people use it.
Here are some basic possible uses, and a quick guide to how it is achieved:
Load up the default patch, Reich Piano Phase, which uses the base riff of one of Steve Reich’s more famous phasing pieces. Hold down the middle C key and keep it held. You will hear that the loops slowly go out of sync and eventually they come back together having shifted through all combinations of sound. This patch is only using the top 2 Phase Shifters, you can see that the pitch knob on number 2 is slightly speeded up, and so is the one shifting forwards. When I use it for basic phasing I find it easier to always leave PS1 set to normal speed. You will also notice that the P1 and P2 buttons are enabled on PS2, this means that the speeding up is timestretched instead of Â the pitch altering. If P1 is switched off, then the pitch will alter with the speed (like a true tape deck). Try loading one of your own loops in this patch and playing with the speed.
Another great use of Phase Shifter is the ability to retune a loop using the P1 pitch shift, and having N (Note Based) pressed. This means that there is no speed change, and so the loops will play in sync. Load the next patch ‘Reich Piano Phase 2′ to hear/see this in action. Playing with the pitch knob on PS2 you will hear that it moves in semitones.
Sticking with the Piano Phase 2 patch, now move the start slider a couple of notches along and retrigger the note (middle C). You will now hopefully hear that WAV in PS2 has begun playback 2 beats in and so there is a delay type effect. This slider will move between 16 equal positions in the WAV.
I hope that gives an idea of some of the basic possibilities, there are also all of these techniques working together, using 2 WAVs and all 4 Phase Shifters some wonderful collages can be created, especially making use of the filters and panning, I hope that the presets will give some ideas of the scope, although I don’t think it is really a preset machine, it is more exploratory. My personal favourite is patch 16 ‘Reverse Guitars’ if you play that lower than middle C and keep the key held down for a long time, it is reminiscent to me of some of the early ambient Eno tracks. Of course it can also be used as a synth and at times has a mellotron type feel. The added SoundScaper also adds another depth to explore.
Hope you all enjoy it!