"Do you want it to sound good or do you just want it loud?" is a phrase I often use when mixing a clients project. In the digital domain, the cumulative effect of turning everything up creates a sum of clipped signals that - to say the least - can be unpleasant. However, one product I turn to that can not only provide clean gain, but also maintain dynamic range is the Oxford Limiter. Let's take a look at what it does and how it might help your mixes jump out of the speakers.

Limiters were originally designed to do just that - limit the amount of volume being transmitted over the airwaves in both the radio and television mediums. Eventually, they found their way into the studios and onto countless hit records. While they still have the same general purpose of program loudness control, the Oxford Limiter has a few extra features that make it exceptionally valuable in the production process.

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Think of the Oxford Limiter as having three adjustable sections with four distinct processes that feed into each other. The first is the Input stage, with a threshold set permanently at 0dB as its normal reference level. It provides up 18dB of gain boost, or 18dB of cut if needed.

The Input level is then fed to the Pre-Process section, which uses look-ahead detection to read peaks before they occur. Here is where you control the transients and dynamics of your audio through use of Attack, Release and Soft Knee compression - which is adjustable from 0dB (hard limiting) to 10dB (max soft limiting).

The Output is fed from the Pre-Process section and features the above-mentioned Enhance function, which is a process that uses sample value limiting to create a unique 'punch' in your audio. Enhance adds a certain richness and sheen to my mixes that I previously achieved through use of hi-end analog gear. Not only do I use it on individual tracks, I typically have it as the final insert on the Master Fader.

The Enhance fader can be adjusted from 0% where there is no effect, to 125% where there is max change. Normal process enhancement is from 0%-100%, where anything above that can increase program density, at the expense of possible distortion (which you could also use creatively). Safe mode will run the Enhancer permanently, with the fader controlling loudness boost. I've discovered that different styles of music benefit from varying amounts of Enhance. The softer the material, the less effect I use, but the dense tracks such as rock benefit from slightly higher amounts (typically around 30-60%). Experimentation is key.

The Input, Pre-Process and Enhance effects feed the Output fader, which adjust levels from -20dBr to 0dBr. Note that pressing the RECON METER button switches the metering into a display for showing the level that will occur in the analog domain after the DAC (Digital To Analog Converter) - otherwise it displays the internal process levels. That's very useful for confirming broadcast mixes, which often require final delivery at -10dB with no peaks above -8dB (see sidebar).

The final process is for dither and noise shaping. You can leave it at 24-bit or select 16-bit for CD's, as well as selecting between TPDF and 4 other types of noise shaping with variable depth.

But what might all of this do for your sound? Just like cooking, you add the process of the Oxford Limiter to taste. Not only can it give you an increase in volume, it can add presence to your audio, while simultaneously providing noise shaping, dither and peak level control. Most importantly, when used properly, it sounds great.

I recommend running though the presets and watching (and listening) to how the settings affect your audio. This will help you adjust them to your own need. Here are a few musical examples and screenshots from a piece of television music I'm working on.

Example 1: features no Limiter inline on the Master Fader

Example 2 features the 'Crunchy' preset. Notice the Input has added 6.2 dB's of gain, the Release is faster than the Attack, there's no Soft Knee compression and the Enhance is set at 100%.

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You can clearly hear the increased gain and overall punch, without pumping or unwanted artifacts. However, with the Slammer preset in Example 3, you can hear the effect compressing the drums and mix, as the Input gain has +18dB on it and the Attack and Release are almost equal. I did this just to show you that you can get those effects if you choose to - and to be careful when using any tool such as the Limiter.

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The best thing about the Limiter is you can quickly 'dial in' a preset, or choose to go deeper into it. Its flexibility allows you to easily vary the process based upon the material, and I typically use it in conjunction with several other plug-ins and a good analog EQ on my Master Fader. Whether it's for music, television, film, video games or the Internet, try the Oxford Limiter on your next mix - you wont be sorry.

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