Recording - November 2011 - 28

B Y PA U L V N U K J R .

Lossy audio is anathema in the pro audio world, and MP3 and AAC files are part of the evil empire where size and convenience come before quality. Unfortunately, for the time being they are part of our audio landscape—and the sooner we get a handle on them, the better.

source, working directly with the Fraunhofer Institute—the inventors of the MP3 and its modern AAC variant made popular on the iTunes Store—to bring us the first plug-in to offer real-time analysis of both lossy and lossless codecs, so we can now make informed decisions when creating said content.

Sonnox Fraunhofer Pro-Codec Plug-In

detail with the Fraunhofer Pro-Codec’s various display options, all in real time. Codecs and settings: The first step is to choose and set up your encoding preferences. Clicking one of the five slots in the codec list brings up a settings window where you choose your codec (see side bar), its bit rate, its mode (both constant and variable bit rates are supported), and its encode quality. Once your choices are made, simply press Play in your DAW and you will be able to monitor your mix through any of

Give your mixes to the world in the clearest possible format

The problem While the process of creating compressed audio files for release is simple, tweaking them for maximum impact is not. Frankly most us of tend to live with the built-in encoding in iTunes, Winamp, Windows Media Player, etc. Occasionally we may use our DAW’s built-in encoder to make us feel more “professional”, but most products use the same algorithms and process developed by the Fraunhofer group back in 1995. Essentially, be it Winamp or Wavelab, the outcome is more or less the same. Aside from size, bit depth and quality choices, there is not much we can tweak. So if we don’t like the outcome, short of re-working the raw file, all we can do is choose a different codec and/or bit depth and repeat as necessary until satisfied... or at least not too upset... or at least we give up and take what the software gives us. Meh. A solution Sonnox has a better solution: the Fraunhofer Pro-Codec plug-in (it’s not available as a stand-alone program). As the name implies, Sonnox went right to the
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Fraunhofer Pro-Codec is a native plugin for Windows XP/Vista/7 and Mac OS X 10.5+ (Intel only). It’s available in RTAS, Audio Unit, and VST formats, and uses an iLok USB key for copy protection. It works in your DAW as a plug-in at the end of your signal chain; it can work in real time on a whole mix, or it can also post-process finished mixed-down files. It works in mono, stereo and surround. Yes, you read that right—you can now audition your MP3 and AAC choices in real time. In other words, you get to hear how your mix will sound as an MP3 etc, and make informed decisions on its final outcome, before you render an entire file! GUI and function The Fraunhofer Pro-Codec plug-in is made up of 3 tabbed windows, one for each of its modes of operation: Online Encode, Offline Encode, and Offline Decode. Online in real time: Online mode is of course the highlight of this plug-in, it is where you choose your encoding formats (up to five), and from there you can audition, compare and analyze them in great

your five codec choices. A green monitor button lets you know which one you are listening through. Displays: At this point you can make codec decisions visually, statistically and aurally. In the center of the plug-in window is a large FFT graph that displays the original input signal in yellow, the difference signal in red, as well as what Sonnox calls the NMR or Noise-to-Mask Ratio in green. Occasionally the NMR line will turn red when codec-induced noise may be audible. This is the clippy-fuzzy sound you typically hear on high frequencies on lower bit rates of 128 and below. Now with this graph you can see exactly which frequencies are being affected. The FFT display also has the ability to show just leftor right-channel information, and the NMR can be bypassed. Just a phase: The display window can also be toggled to Phase Display, where you can view the phase envelopes of the input and output, the output and difference and just the difference at 5x magnification. Overall, these tools let you see, for the first time, exactly what each encoding process does to your sound file.

Recording - November 2011

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