Q:

How to use unison without voice beating/phasing

I've been learning to make trance and progressive house for the past few years, and have always encountered the same problem when creating sounds with unison, eg. plucked saw chords.
Every few stabs the voices align in a way that causes resonant peaks at certain frequencies, especially in the low end. I can't seem to correct this with EQ, as the frequency of the peaks vary throughout the part.
To give you an idea of what the effect sounds like, see example below (most noticeable at 5 and 15 seconds):
http://www.mediafire.com/listen/q2en6gf7498n3jk/unison_phase_issue.mp3
A workaround I have used is to record the part several times and manually piece together the best bits - but this takes forever, especially in automated sections, and only works for sounds with low polyphony. Is there a synthesis technique I could use to prevent this from happening?
Cheers for any info.

A:

Beating will always be there whenever there are two or more signals close in frequency but there are a few things that may help, depending on the synthesizer. All options will make it sound different but that is a trade off you can't really get away from... The reason these sounds stick out is actually because of the beating. 

More unison voices. The more voices you use the less chance peaks and troughs will match up
Random oscillator start phase (or free running oscillators). This will at least take care of problems in the transient. 
Try different waveforms. Unison with simple sines will have more pronounced beating than saws.
Don't do unison on low frequency sounds. If you're making a monophonic bass sound, play the unison sound an octave up and a non-unison on the original octave. On a chord, like a pad, you may want to similarly let the lowest note or notes be without unison. 
Use a chorus effect instead. For many types of sounds a chorus effect will create a similar timbre. Since chorus is modulated it won't create the same extreme beating.
Stereo spread. This will turn the beating into stereo differences instead. Note that the moment you go mono your beating will be back...
Try a different synthesizer. Implementations of the unison effect may be different and better suited to your needs in others.

Good luck!

