In case you don't already know, iZotope RX is an audio processing suite that focuses on restoration and repair of damaged audio. You can use it to remove most any type of noise or anomaly via its various processing functions as well as through the use of spectral editing. It's been approximately three years since the release of RX 2 and now the latest incarnation (RX 3) brings a bevy of useful enhancements as well as a number of new features. Both new and improved features include: a revamped user interface, updated Channel Operations, Declip, Declick, Denoise, and Gain functions, new Dialogue Denoiser, Dereverb functions, and the bundled Insight metering software, plus more. As before, RX 3 comes in both Basic and Advanced versions with some of the RX 2 Advanced functions now available in RX 3 Basic, such as Plug-In Hosting, Dither, and Resample.
RX Interface and Workflow
While the structure of the main interface remains familiar, you'll notice the nice, modern color scheme immediately with its subdued grays and blues (with gray/white text) for the main elements, which brings more focus to the data displays. Some specific changes include the addition of a Bypass button on each module for quick, one-click comparisons. A new playhead has been added to the edit window, which provides scrubbing. And most significantly is the addition of a tabbed interface that allows you to open up to 16 audio files simultaneously for track comparisons, easy copying/pasting, etc.
Another significant addition that improves workflow is the RX Document file format. Instead of having to save a finalized version of your file, you can now save the RX editing session. The RX Document format preserves the entire undo history of your session (as well as marker positions) while leaving your original audio file untouched. This means you can apply whatever processing you like and come back to make changes any time in the future. Essentially, it makes all editing and processing in RX non-destructive.
The one new feature that you'll probably notice immediately is the Dereverb Module. It does exactly what its name implies and allows you to reduce the amount of reverb in an audio signal. You simply select your audio, click Learn, and RX 3 automatically processes the selection with some suggested settings. From there, you can adjust the amount of reduction or even go in the opposite direction and add more reverberation to the signal. In addition, you can adjust the Tail Length, as well as the reverb amounts in the Low, Low-mid, High-mid, and High bands for more accurate processing. An Enhance Dry Signal option provides some automatic processing to try and bring more focus to the source audio. Depending on the material, the results can be very good, although you usually can't remove all reverb without adding artifacts.
Another brand new feature that many film and video production people will find useful is the Dialogue tab in the Denoise module. This is a simplified version of the Spectral tab, although when I say simplified, I really mean more focused towards processing speech. The Dialogue function provides 64 band-pass filters that are specifically tuned to work with spoken voice. You simply select a noise-only portion of your audio and click Learn to define a noise print. From there you can manually tweak the noise print or Threshold, as well as adjust the amount of Reduction. Additionally, because the Dialogue function requires less processing power, it can be run in real-time. This means you can apply the plug-in to the dialogue tracks in your video editing software and use the Auto mode to automatically adjust the noise print in real-time. Auto mode is also useful when you don't have a clearly defined noise print available.
Added to the Time & Pitch module, the Pitch Contour function allows you to adjust the pitch of audio over time, which also affects the length of the audio. You select your audio, and then create a pitch curve (envelope) by adding and adjusting points. You can also adjust the transition between points to be abrupt or smooth using the Smoothing parameter.
More often than not, you'll find that any clipping in your audio will be different at the top and bottom of the waveform. To compensate for this problem, the Declip module in RX 3 now allows you to do asymmetrical declipping by adjusting the Threshold separately for each boundary of the waveform. This results in a much more accurate and cleaner result. You can begin by clicking Suggest to have RX 3 automatically set the Threshold and then manually adjust from there.
Audio Restoration At Its Finest
Aside from what I've already covered, iZotope says there are a large number of other fixes, improvements, and tweaks that have gone into the development of RX 3. Depending on your needs, you can choose between the Basic and Advanced editions, which are separated by both features and price, although I think many users will find Basic to be very functional for many audio restoration situations. However, if you have the means and you want the best software in this category, then RX 3 Advanced is the answer.
For more information, visit iZotope.com.