I'm quite surprised there aren't more reviews of this yet; I'm a little honoured to be the first, as I feel this is arguably one of the best software compressors available right now.

I have to say I was pleasantly surprised when FabFilter announced they had released a compressor. Now at this point I already had my fair share of compressors, but I was curious to see what a company with a reputation for ultra-high quality plug-ins would put out, so I downloaded the demo and got to it.

First, the GUI is striking both in its beauty and simplicity (much like their other offerings!): the colour choices complement each other and provide plenty of contrast, and the over-sized dials beckon to be tweaked. But what is really interesting here is the variety of ways the user can witness realtime feedback of the compression transfer curve, peak reduction and sidechaining. While we've all seen the transfer curve before, and I can think of one or two older plugins that attempt to show the effect on the peaks via a waveform display, I had never seen a display that shows the compressor "dipping down" over the peaks, showing you when and how it's compressing; you will see little dips on the top flatline when gain reduction occurs, and if you increase the attack, you can see how the GR happens more slowly, i.e. the dip indents to the right. This makes it valuable both for experienced tweakers and beginners, who may benefit from the extra visual representation (compression is often one of the hardest concepts to learn!).

Next I noticed an "Expert" button; click this, and amazingly the whole waveform display animates and slides "underneath" the transfer curve, revealing sidechaining options and sliders for the pass filter. Again: clear and clever graphical representation, with plenty of options, which we'll get back to.

The larger knobs above are all familiar paramaters: Attack; Release; Threshold; Ration, etc; plus a soft/hard knee switch, three types of compression characteristics and even a dry/wet knob, which I love. With all these options, I couldn't wait to hear it, so let's go!

Even with the default setting, I notice a pleasing response on my drum loop; the transients are punching through, the decay has been extended a bit and the peaks are under control. The more I experiment with more dramatic ratios and settings, the more I like it; this unit reaks of quality, and I know I'm getting hooked by the second! I try the different characteristics, and I can hear differences between them ("Classic" seems to have a softer attack, for instance), but I can't decide which I like best! Everyone wins!

And with the Dry/Wet knob, you can smash the hell out of the signal, but use the mix knob to dial the dry signal back in, New York-style! I found driving the input wasn't that great for this, relying on the threshold and ratio gave better crushed results. ;)

(Another great note about the interface: when you pause over any element, a rather adorable little word ballon will appear and explain the object in question; again, extremely useful, especially for beginners and people looking for further explanation of the Pro-C ethos.)

I then poked around with the presets, of which there are many - categorized by style (nice!) - and I even noticed "bM" after most of the presets; I wondered: is that our "bManic"!?! Sure enough, it was. He was a beta-tester and preset-maker, and could explain why this plugin felt like it was made for the KVR crowd; I really felt like someone was listening to me (like that time you were at the AC/DC show, and you felt like they were playing for YOU..yeah, you KNOW what I'm talkin' about!), and that's reflected in Pro-C; it's made by a discerning small company for the discerning few (although I think everyone should have one, of course!). My point is: the presets are excellent starting points, and very useful for slobs like me who don't spend a lot of time with things like M/S processing; and the presets help demonstrate the strengths of FabFilter's design.

The Help file is perfectly well-written and laid out, I'm glad they used a cfm-style Help, I prefer that to launching a page. Not that I've had to use the Help File much, if at all; the interface is all there, and having direct access to bManic and the developers makes it almost uncessary. But it's there for those who need it.

Support has been friendly and excellent. I submitted a request for A/B, and not only was it met with enthusiasm, it's there now in the 1.1 release, along with (!) Undo/Redo. Amazing.

Now, this compressor is not cheap. At $199, it's near the top of VST compressors, but I must be clear that it's near the top in terms of sound, quality, GUI & support. This is a full package, the "real deal"; and I did not hesitate to pull out my credit card for this. I would warn anyone who is serious about compressors to check this out immediately; one my proudest purchases. :D