Recording - November 2011 - 58

...where we bring you follow-up articles with application hints and upgrade news about gear already reviewed in Recording

iZotope RX 2
A brand-new prescription for healthier audio

by John Rossi III

t’s hard to believe that it has been three years (June 2008) since I had the chance to review iZotope’s initial release of the stellar audio restoration suite RX. Being of the belief that RX represented about the best it could possibly get, I was very surprised to find that iZotope had released a completely new version of the suite, with a name that suggested the new package was somewhat more than just a major revision of the original RX. Well, they did, and, it is! Two versions Like the original RX, RX 2 is available in two versions, RX 2 and RX 2 Advanced. RX 2 will probably be suffi- Fig. 1 cient for more than 90% of the people likely to read this article. RX 2 Advanced adds some operational features to several of the modules that will be of greatest use to audio professionals who spend significant time cleaning up audio projects. RX 2 Advanced also contains several of iZotope’s standout audio processing applications, including 64-bit SRCTM sample rate conversion, MBIT+TM dithering, and Radius time stretch algorithms. In addition, RX 2 Advanced allows external VST plug-ins to be used from within the spectral display for processing only selected regions, and Advanced also provides a completely new class of processing called De-Construct. This latter module allows the tonal and noise components of an audio file to be separated so they can be independently manipulated. These and other differences between RX 2 and RX 2 Advanced will be more specifically delineated in following sections that more completely describe the action of the modules.

While RX allowed interacting with the spectral display editor using only time, time/frequency, and frequency ‘rectangular’ box selections, RX 2 now sports buttons that additionally allow elements of the spectrogram to be selected using a paintbrush (a round “brush” with diameter variable between 4 and 100 pixels), a lasso (that allows arbitrarily defined lassoed portions of the spectral display to be selected), and a magic wand (that selects individual tonal events as well as their harmonic overtones). If you are familiar with the function of these selection tools in your favorite photo editor, you will be comfortable using them in the context of spectral editing in RX 2. RX 2 makes removing audio artifacts from audio as straightforward as removing unwanted content from digital photos. Inside RX 2: tests and examples iZotope RX was comprehensively reviewed in the June 2008 edition of this magazine. As indicated above, several modules have been added, and others have been given additional functionality or a reworking of their processing algorithms. The following is a summary of the modules, with a look at what’s new and what’s improved. For several of these module tests, I have provided screenshots in this article, and generated some short audio examples of Before and After. If you’d like to hear what I did, check out the Audio Examples for this review in Recording’s online Resource Library. Look under Magazine Extras > Audio And Music and look up this month’s issue and article. Declip: The standard single-band mode of RX’s Declipper remains cosmetically unchanged in RX 2. RX Advanced, however, added a second multi-band mode that I have used on occasion to process difficult digital clipping artifacts. This multi-band mode is no longer offered in RX 2 Advanced. That’s right, something was removed from version 1 to version

New user interface Upon initial execution, besides being almost three times faster in opening audio files than RX, the most notable change in RX 2 is in the overall update to the user interface (UI). RX 2 vertically aligns the task-selection hot buttons on the far right side of the UI, and presents the user with more choices than its predecessor. In the standard version, buttons are available for the Declip, Declick & Decrackle, Remove Hum, Denoise, and Spectral Repair modules, as well as for direct access to Gain (for processing gain and fades), EQ (which is similar to the eq available in iZotope Alloy, reviewed September 2010), Channel Operations (for channel mixing and phase rotation), and Spectrum Analyzer functions. The Advanced version adds buttons for direct access to 64-bit SRCTM, MBIT+TM, Radius, as well as to Plug-In call, and De-Construct. New editing tools Did you ever wish that you could edit nuances in your audio files the way you use a photo editor to edit nuances in your digital photos? Well, thanks to the new editing tools provided in RX 2, you can.
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RECORDING NOVEMBER 2011

Recording - November 2011

Table of Contents for the Digital Edition of Recording - November 2011