ButterCompDemo was a technical experiment that turned out interestingly. The plugin itself ended up getting rolled into CStrip, with its users crossgraded to CStrip. Here’s how it worked.
If you have one compressor, you adjust the overall volume of the sound according to how loud it is. This can produce odd harmonics depending on how it affects the waveform, but not so much even harmonics because it doesn’t affect the waveform on one side only. (Compressors that kick in on only one polarity will make even harmonics, but have to kick in harder when they engage)
If you have two compressors on opposite polarities of each other, you can do separate compressions for each half of the waveform. This requires blending between the two sides, but it means most asymmetrical signals will get compressed differently on each side.
That’s not what ButterComp does.
If you have two compressors, alternating each sample, you get an unusual response which behaves differently to high treble frequencies than an ordinary compressor would. It can catch treble sounds and attenuate them on one compressor while the other doesn’t kick in, because high frequencies can peak out on alternating samples. This isn’t a neatly calculated effect, it produces a particular sort of artifact but that gives it a sound.
That’s not what ButterComp does either.
If you have FOUR COMPRESSORS, alternating each sample and also handling opposite halves of the waveform (still on a single mono channel, remember)… that’s what ButterComp does.
The result was a compressor that turned out… almost inaudible. It’s not an aggressive compressor at all. ButterComp had just one slider (the CStrip implementation added a speed control) and a limited amount of compression on tap. Its strength was in the transparency and inaudibility of the ‘squish’. A few people went nuts over it, while most everybody else didn’t get the point of a compressor you couldn’t hear working.
If you’d like ButterComp, buy CStrip and ask me for it in email. I’ll send it.