PSP Xenon Mastering Limiter/Leveler Plug-In

Traditionally, mastering has been the domain of professionals, and for good reason! Back in the days of vinyl, an improperly mastered record could definitely sound terrible, and could possibly not even by playable on some turntables. Mastering grade consoles, processors, amplifiers, and monitors remain expensive. I don’t think this will be changing any time in the future, but what has changed is the availability of mastering grade software equalizers and compressor/limiters at affordable prices.

That brings us neatly to PSP Audioware’s Xenon mastering plug-in ($249) which includes mastering essentials such as a two-stage limiter, integrated leveling amp, absolute inter-sample peak prevention and word-length reduction (requantization) with three noise-shaping options. Xenon features 64-bit processing and will support up to 192kHz files. Although I ran the VST version on a Dual Xenon workstation under Magix Sequoia 10 and Steinberg Nuendo 4, Xenon is also available for Audio Units and RTAS hosts running on PCs, PPCs or Intel-based Macs.

It’s easy enough to get the hang of Xenon when you realize that its first stage of limiting provides most of the gain reduction that will take place. The input and transient controls will determine the initial threshold of limiting, much in the same way that an analog limiter would. Xenon’s second stage uses look-ahead based brickwall envelope detectors to eliminate the possibility of digital overs. Next in line, is a switchable option to enable the envelope detector to prevent inter-sample peak distortion in the digital to analog processors that will ultimately play back the material. This is accomplished by preventing full scale signals from being included in the output.

Reminiscent of some of the popular analog domain devices in the past, Xenon includes a leveling amplifier which is really nice for adjusting the “macro-dynamics” of the material being mastered. Basically this is a final gain reduction stage with a very slow time-constant that prevents the limiter from “pumping” as it recovers from a loud section.

Mastering engineer Bob Katz has developed the K-System of metering, which is a simultaneous multiformat type of display which shows true RMS and peak levels as well as crest factor. Once you get the hang of it, it really allows you to understand the concept of loudness in a more concrete way. In addition the K-System allows for three metering variants/scales based upon commonly accepted monitoring levels, which are calibrated to broadcast (12 dB), CD production (14 dB) and film production (20 dB). Speaking of calibration, Xenon includes an on-board pink-noise generator which makes setting up levels relatively quick and easy. Xenon uses the ubiquitous iLok system for copy protection. Registering Xenon at PSP Audioware’s site was straightforward and the iLok authorization was ready to download in about two hours.

Although Xenon is mainly targeted towards use in the mastering stage, I also found it very useful in other applications as well. Xenon can do some amazing things to an ambient drum track that would normally require some specialized hardware. I’m a fan of the sound of radical limiting especially when combined with “trashy” sounding sources, and Xenon allowed me to quickly and effectively dial that in. The included leveling stage keeps the sound constant, without the annoying pumping that’s often the hallmark of extreme processing.

I found that Xenon allowed me to easily arrive at a more polished and dynamic sound more quickly than some other mastering-oriented plug-ins that I’ve previously used. I did find that it took a little while to get used to the K-System metering. Once I did, however, I was left feeling that “conventional” metering leaves quite a bit to be desired. Whether due to the 64-bit internal processing, or just the overall software design, Xenon was free from digital sounding artifacts such as the perceived loss of depth and stereo image quality. While it is possible to make sources sound flat and lifeless (but LOUD!) even fairly aggressive processing still can yield a natural sounding result. My kind of plug-in!

Xenon delivers the goods when it comes to mastering-quality limiting at a very low cost compared to other high-quality tools. Superb sonics, a nicely designed interface, excellent value, and groundbreaking metering coalesce to make Xenon an easy product to recommend. Prospective purchasers (who already have an iLok) should take note that PSP Audioware offers a fully functional 14-day demo on their website.