I'll typically only use it when I have a problematic vocal, like a vocal recorded in to reverberant a space. It’s a fun and effective way of controlling dynamics and adding harmonics. Backing vocals should be thought of more as instruments than vocals. If you’re going for a modern, in-your-face vocal, it’s common to use parallel compression. The interlude from Knights of Cydonia by Muse is a great example of terribly overcompressed backing vocals (even though it kind of works for this context). I like parallel for other things like drums (acoustic drums) and love it on the 2bus. Parallel compression’s a great way to keep a sound natural while putting it “in the pocket.” Another great use for compression on vocals is to make the vocal sound thicker – particularly in rap. Parallel Compression A commonly used technique to make the vocals to pop out in the mix is to send it in to a bus or duplicate the track, and applying heavy compression to the duplicated one. Can't comment on the CL1B, but I rarely use parallel for vocals. Rap isn’t really supposed to be “pretty”, so I don’t worry if the compression becomes a bit audible. In situations like that I find it can be helpful. Parallel compression is helpful for changing the tone of an instrument, rather than leveling out its performance. Subtle parallel compression doesn’t only work well on vocals or drums. Simply send the vocal to an aux channel with an aggressive compressor (like the CLA-76 or dbx 160), and smash it to smithereens. Don’t be afraid to use high ratios, fast attack and release times, and low thresholds. Thicker Vocals. A general rule is to apply just enough compression to distinguish them from the rest of the mids, but never so much that they overshadow the lead vocal.. Basses, drums, vocals and so on can all benefit from this wonderful powerful technique. 8. Parallel compression is only the tip of the iceberg when it comes to parallel processing. For the meat ‘n ‘taters of parallel processing, refer your good self to the “5 Ways to Use Parallel Processing in Music Production” article. For a rap vocal I’m going for a pretty quick release, and I’m doing 4:1 up to 8:1. You can create some extremely aggressive compression that brings out the saturation and color in the compressor, and then mix it in ever-so-slightly for more "vibe" to your vocal… Another great use for compression on vocals is to make the vocal sound thicker — particularly in rap. Rap isn’t really supposed to be “pretty,” so I don’t worry if the compression becomes a bit audible. For a rap vocal I’m going for a pretty quick release, and I’m doing 4:1 up to 8:1. Thicker Vocals. For rap and hip-hop, I recommend trying parallel compression on vocals, and parallel saturation on bass, kick, and snare. From there, adjust the levels between the parallel compressed track and the original one; Always remember to be subtle when doing this, a little goes a long way. In the Layering Vocals using Parallel Compression video, I show you how to set up for parallel processing and in particular how to use NY Compression. Sometimes, you might want to control an instrument’s volume without making it too obvious. Step 9: Even more (parallel) compression.