It?s an effect that?s heard on many recordings, often subtly ? like when a rock rhythm guitar is sidechained with the kick drum, so every time the kick drum hits, the guitar volume dips slightly for that instant ? giving a really powerful overall effect? The guitar sounds pumping, or spring-loaded! Or it?s sometimes used strongly, to make the signal completely disappear with each kick drum, as in big 4-on-the-floor club tunes. All we?re talking about is change in volume ? the Deep Space Pulsar doesn?t affect your tone in any way, and sounds great with bass guitar!