I've previously reviewed RX 3 [Tape Op #100] and RX 4 [#105], and with iZotope's update to RX 6 last year, I think it's time to once again point out what a powerful set of tools this application and plug-in suite is. Of all the software and plug-ins I use, at this point in time, RX 6 is the one that I cannot live without. If a studio I am working in doesn't have it, I will install it (it's easy to authorize), or I will set aside "tasks" to perform with it later on my laptop. I have also employed (and extolled the virtues of) RX in many of my Lynda.com instructional videos over the years. So how do I use it? Quite simply, RX 6 allows me to tailor audio tracks (in the recording or mixing stage) to what I really want to hear. Importing audio into the standalone application (linked to Pro Tools or other DAW sessions via the RX Connect and RX Monitor plug-ins), a spectral view of the audio is presented on-screen, with time, frequency, and amplitude in one view. I can use Mouth De-click (new!) to easily and accurately remove distracting mouth sounds I don't want to hear on vocalists. I can select certain frequencies on a bass guitar, and cut or boost them with Gain — in specific parts of the song — for an evenly leveled signal to mix from. I can erase guitar and amplifier hum with Spectral De-noise. I can sample the unwanted ring of a kick or snare drum and remove the ring from drum tracks by using Spectral De-noise in a way its inventors probably didn't imagine. With Spectral Repair, or Gain, I can eliminate vocal plosives and mic stand rumble without affecting frequencies above it — far better sonically than the old "high-pass EQ" trick. I can use De-ess in the standard way on vocals, or I can use its Tame Harsh Master preset to make a Shure SM57 sound more like a Neumann U 47 on a bedroom vocalist.
In other words, iZotope RX 6 allows me to control my tracking, and prepare mixes, with a power I never had before. Every "compromise" I used to experience, where I could only get a track to sound "good enough," is now a juncture where I can go a step further and pull off the previously impossible. I tell all my recording peers about what this can do for them, and many give a wink and a thumb's up as they already know. But many others think I'm talking about some science fiction fantasy, or an unneeded amount of extra work during sessions. They will wake up one day, as this type of control is the future of audio mixing. Equalization and compression have become simply flavors in my toolkit, and are no longer the corrective necessities they once were.
As I took too long to write about it, RX 6 will undoubtedly be updated to its next version soon. Just like this update, we will once again see some new features and a smarter application. Every update of RX seems capable of identifying and fixing problematic sounds with more finesse and less artifacts. It also becomes easier to use, and as more modules are added, they all seem to fulfill specific needs of users, which I find encouraging. I'm in for life; you should be too.
One tip: Sign up for iZotope's email list. They constantly host special sales on RX and many of their other fine software products.