I think the API Vision is the most fun channel strip plugin UAD offers. I’ve never worked on a hardware Vision so I can’t compare the sound or vibe, but I love tweaking on this plugin. And something about the layout attracts me like no other lover. (Or SSL.)

The channel strip is available for Luna (to make a virtual API desk), a version for standard UAD, and a ‘legacy” version.

Each module on the channel strip is pretty cool. The API 212L preamp, the API 550L EQ, the API 515L filters, the API 225L compressor/limiter, and the API 235L gate/expander all add some character individually.

Some of the changes from the legacy plugin are the addition of a line emulation in the preamp module and a more comprehensive EQ in the Luna implementation, along with the whole API desk thing.

They all seem to be pretty much the same as far as their harmonics, although the Preamp is a little less noisy in the low end. What I find most interesting is how the frequency analysis for the “old” legacy channel strip and the “new” preamp are the same with that slight low end bump, whereas the “new” channel strip is different from both. I would think both of the “new” plugins would match(?).

Basically, the tests are the same between the legacy and the new version. This is a departure from all the other “legacy” UAD versions—which don’t model any harmonic distortion or non-linearity. There were DSP limitations when they were first introduced, but as more processing power became available UAD redesigned them into more analog-sounding plugins. This is not the case with the API Vision channel strip, the emulation appears to be very similar, if not the same. It seems like UAD is now going to use the term “legacy” for any “old” plugin that they have updated (for Luna or whatever) even if nothing about how they sound has been improved. (You can decide for yourself if it is worth paying for this!)

Hints:

The gain/preamp is special on this. Just tickle the red* to get distortion on the loudest peaks, a trick that helps vocals (or anything, really) cut through the mix. Plus, it sounds so vintage when you do that, even though the API Vision is a modern device. The hi- and lo-pass filters are super cool too, especially when tracking.
The Preamp plugin is really loud, just saying. You may have to use the pad when you normally wouldn’t think about it.
The Hard setting on the compressor gives a real limiter kind of feel. You can use it to just take off the tops.
Be careful if you make large EQ changes, especially boosts, as the Q gets narrower the bigger you go. (But you wouldn’t be making large boosts anyway, would you?) This is part of the charm of API EQs.
Because of the previous hints, the API is an awesome Unison plugin. You can do subtle limiting and EQ, and add just a bit of flavor to anything you are recording. This is also the philosophy behind the Luna integration.