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Old 5th July 2013 | Show parent
  #18
ValhallaDSP
 
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Quote:
Originally Posted by The Famous Yard ➡️
I think Soundtoys Microshift is based on the Roland and is free. It's great sounding either way.
Microshift has two parallel pitch shifters. The left channel is shifted up by a certain amount, and the right channel is shifted down by the same amount. This causes a "static" chorus, and creates a wide stereo image.

The Dimension D doesn't use pitch shifting. Instead, it has two bucket brigade delays, modulated by a triangle LFO. The triangle LFO modulation causes an up/down pitch trill. The LFO is inverted before modulating one of the delay lines, so the pitch shift trill in one channel is opposite of the other channel. In other words, one delay has an up-down-up-down pattern, while the other delay has a down-up-down-up pattern. If you mix these two together, the result is a "detuned" chorus: up+down, down+up, up+down, down+up...

The Dimension D has stereo outputs, arranged in a way kinda similar to this:

outLeft = delayLeft - delayRight
outRight = delayRight - delayLeft

There is also a cool EQ trick, where the "antiphase" component (i.e. the part subtracted from each channel) is highpass filtered, and the dry signal has its low frequencies boosted in a way that is complementary to the highpass filtering. This keeps the bass frequencies from cancelling out.

I'm sure that there are other quirks going on, but this is the basic topology of the Dimension D.