Recording - June 2014 - 34

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

iZotope RX 3 Advanced Audio Restoration Suite
by Paul Vnuk Jr.

Formerly impossible audio rescues become commonplace

Now it's time to talk audio cleanup and
restoration, as we take a look at the latest
version of iZotope's RX software. iZotope
is an American software company that
offers complete audio suites optimized for
specific tasks such as mixing (Alloy), mastering (Ozone), vocal processing (Nectar),
and of course audio restoration (RX). A few
months back (February 2014) we took a
look at the latest version of the Nectar
vocal processing suite; and prior to that in
our December 2013 holiday gift guide I
reviewed the full-featured Insight metering
suite.

RECORDING June 2014

In a bit of irony, iZotope has a plug-in
called Trash 2, whose goal is to mangle,
transform and distort your audio... and then
offers a suite of plug-ins to scrub it clean
again! RX is considered one of the best audio
restoration suites in both the recording studio
and the world of forensic audio.
Recording reviewer John Rossi gave us
a detailed runthrough of RX in June 2008,
and then discussed the new features in RX
2 in November 2011. If you really want a
full picture of all that RX has to offer from
stem to stern, it's worth seeking out those
past issues. While we will take a quick
jaunt though RX 3's complete feature set
so new readers can learn about its layout,
it's the changes and new additions that
we will be focusing on this time around.
RX 3: What it is, what it offers
RX 3 runs as a collection of individual
plug-ins for use in your favorite DAW, or
as a comprehensive standalone program
where the plug-ins are referred to as modules. It is available in two packages, the
standard RX 3 version and RX 3
Advanced, which contains a lot of extras
(and which is under review today).
RX 3 contains the following repair-based
plug-ins/modules: Denoise, Declip, Declick,
Decrackle, Spectral Repair, and Hum
Removal. RX 3 Advanced adds Dereverb
and Dialogue Denoiser, as well as more fullfeatured "advanced versions" of each of the
above modules. It also adds the Deconstruct
module in when used in standalone mode.
When run in standalone mode, RX 3
becomes a restoration-focused 2-track editor of sorts. The standalone version includes
a 6-band parametric EQ, channel and
phase control, a spectrum analyzer,
iZotope's 64-bit SRC sample rate conversion and MBIT+ dither modules, third-party
plug-in support and audio recording and
monitoring. RX 3 Advanced, when run in
standalone, also adds iZotope's Insight
metering suite, a Time and Pitch module
with Radius and Pitch Contour, and Center
Channel extraction, as well as Azimuth
Alignment for tape reconstruction.
Most of these, like Denoise, Declick,
Declip and such, should be pretty selfexplanatory, while others are unique.
Deconstruct is something I have never seen
outside of RX; you can separate an audio
source into its separate tonal and noise
components and treat them separately-

such as the breaths and spittle clicks a
singer makes when singing, vs. their sung
notes. Amazing stuff.
The big new(s) in 3
While sporting a new look, RX 3 concentrates its new features in RX 3
Advanced. These include:
Dialogue Denoiser: As its name implies,
Dialogue Denoiser (according to iZotope)
uses a newly designed algorithm specially
"tuned to keep dialogue as pristine as possible". Like the Advanced version of the regular Denoise module, Dialogue Denoiser
offers both a manual fixed noise print setting
as well as an adaptive variant that tracks
and compensates for noise changes.
I do a lot of audio cleanup for podcasts
and videos and have been using this as
my main denoiser for a few months now...
and I am really impressed. I am not sure
exactly what this new algorithm is doing,
but for speech and interviews Dialogue
Denoiser is much less invasive, even at
higher levels of cleanup, than the normal
Denoise-especially with how easy it is to
add points to and manually alter the noise
print curve.
Dereverb: This is the other big news of
RX 3. As its name implies, it lessens the
sound of reverb and/or the environmental
space in location and studio recordings.
While I am aware of other dereverberation plug-ins like Zynaptiq's Unveil, taking
reverb out of existing audio still sounded
to me like a gimmick or snake oil. But you
know what? It works!
Every week I record a Pastor speaking
with an omnidirectional headset mic in a
large, echoey, 1800-seat concrete-walled
sanctuary. After the sermon, I clean up and
place said sermon online as both a podcast
and video excerpts. In the past, I would try
and EQ out the boomiest frequencies in the
audio and gently try and gate others, with
acceptable results after a lot of work. For the
last two months, Dereverb has changed my
workflow entirely.
Like Denoise, Dereverb learns a noise
print (or "reverb print", I guess) of the
recording, analyzing wet and dry ratios
and reverb tails. Then you get four separate frequency sliders (low, low mid, high
mid and high) to minimize and mask out
the offending reverberant tones. There is
also a master fader to control the overall
effect. While I reiterate that it truly does

Recording - June 2014

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