In this article we share 5 tips and tricks that even the most seasoned user of iZotope’s RX software might not know. Think you know RX well enough? Looking for some new technique to amaze and enlighten? Read on!
The Fab 5
I’ve been using iZotope software since someone first showed me the original RX. Over the years, I’ve experimented a lot with the various tools in the standalone software, the heart of RX. This article represents a fun collection of 5 unique functions I’ve found that I think you might just want to know about.
More Reverb Please
Recent iterations of iZotope’s RX software contain the stunning Dialogue De-Reverb Module, crafted atop machine learning and developed using a mountain of real-world test audio files. Before this modern wonder came into being, RX offered the venerable De-Reverb Module, which as I shall explain, actually does at least one thing its successor cannot! I feel it’s likely part of the reason De-Reverb hasn’t been ‘De-Commissioned’.
First, send some reverberant audio from your DAW or drag and drop a file from your desktop onto the RX standalone’s spectrogram. From the modules list on the right side of the spectrogram, open the De-Reverb module. Make a selection and hit ‘Learn’. The module usually does an admirable job of figuring out how to deal with your sound but if not, move the sliders up and down for each band, soloing to fine tune the amount of reduction.
You’ll get a decent result. It doesn’t take long (This is not the interesting bit).
The thing that differentiates De-Reverb from Dialogue De-Reverb is there’s a negative end to the ‘Reduction’ slider. You can actually add reverb as well as take it away! The three audio files below demonstrate the original sound, the reverb-reduced sound and the reverb-increased sound. I recorded myself in a hallway for the purpose of this test. I’m sure you’ll agree, this has wonderful possibilities in terms of matching dialogue or other production audio and even for music samples.
A Clean Sweep?
The Signal Generator is tucked away as a utility in the RX standalone software. What makes this signal generator special is it’ll add silence to timeline selections and the tones it creates can be shaped in a variety of ways.
I’ve used the signal generator to create tone sweeps for recording impulse responses and interesting pitch sweep effects like digital button sounds. The great thing about this generator is that the duration of the sweep is determined by the length of the timeline selection in the RX spectrogram! You can make any duration of sweep with tonal shapes ranging from sine, triangle, sawtooth and square wave. In this example file I did quick 1kHz to 6 kHz sweeps up and down using sine, sawtooth and triangle shapes. As a sound design tool, Signal Generator is found gold!
Rotate This!
Encountering a lopsided waveform for the first time can be unsettling when it’s extreme. Often seen in brass recordings, sometimes encountered in dialogue or even stereo music, asymmetrical audio recordings are viewed as unbalanced between the positive and negative excursions of the waveform. In this example, I have slightly more energy above than below.
My true peak reading in the Waveform Statistics window says 1.01 dB which is close to full scale. I open the Waveform Statistics window (Option+W) before sending anything back to Pro Tools since RX is a 32 bit floating point editor (peaking above 0dBFS is possible) and I usually mix at 48 kHz, 24 bit (peaking above 0dBFS not desirable in a fixed bit depth audio file). If I send any file back to Pro Tools that’s peaking above 0dBFS I will clip the audio.
Sometimes my levels are otherwise where I want them to be but I just need a little more headroom. By rotating the phase to balance the waveform I don’t affect the sound but I can buy myself that extra space below full scale. Even in this modest example, I earned myself .74 of a dB. I’ve had instances when I’ve managed to recover 3-4 dB of headroom using Phase rotation. Lopsided sounds can clip more easily than evenly balanced audio files so this trick, as abstract as it may seem, has practical implications.
Plug It In
Every time I install a copy of RX, I go through the Preferences. In the Plug-ins tab, I enable ‘Audio units’ and ‘VST plug-ins.’. After a few moments, all the AU and VST plugins on my system populate and are available for use inside the RX standalone software. This only needs to be done once per user profile. As you can see in the picture above, not every plugin loads properly but the majority have no issues.
Enabling plugins not only allows me to use my favourite plugins inside RX without leaving the program, it also allows me to use plugins in two formats Pro Tools does not support, AU and VST. With plugins engaged, I can now access and use software offerings not available to me inside my DAW. I can also use AU and VST versions of my favourite tools to help RX dramatically extend its range of processing options.
In this example I used a plugin found in Logic Pro X to apply distortion to a piece of dialogue. The waveform looks a little lopsided (If only I knew a trick to even that out!). RX has now imbued the power of Logic plugins onto a Pro Tools user! Of course, you can access the RX standalone software from most major DAW’s.
And For My Final Trick
I shall make modules disappear!
That module list along the right side of the spectrogram looks pretty crowded to me.
If you click the light gray ‘down’ arrow next to the word ‘All’ near the top right of the spectrogram (under the ‘Repair Assistant’ bubble) you can quickly select a quick filter to reduce the amount of visible modules. For example, ‘Dialogue & Voice’ leaves our module list looking like the second image above.
I created my own filter by clicking on the three little white lines to the right of the filter presets (again, near the top right corner of the spectrogram).
Adding a new filter allows me to customize the name, then the whole module list turns into a load of checkboxes that can be de-selected to reduce screen clutter. This really tailors the list to speed up module selection.
Final Thoughts?
Since the day I started exploring the deeper aspects of RX when I purchased RX2 many years back, I’ve thought the real power of iZotope’s RX software lies in the mastery of the standalone tools. We don’t all have loads of time to poke around inside software so I hope this quick read has added a trick or three to your workflow.
There are plenty of creative ways to use this software which is why it has become the universal toolbox for sound editorial.