It's been a long time since I ended the practice of stacking processors in the transmission audio chain. So long that when this need arose I found myself waxing nostalgic about boxes like the Texar Audio Prizm with its requisite Orban card 5 hotrod. I've often added boxes on both sides of the core audio processor: Modulation Sciences composite clippers, Orban XT chassis, UREI 1176s, and the Aphex Compellor, to name a few. Always the goal was to attain dial presence and consistent listenable sound. With digital processors, everything changed. Now the stations' sound could be treated, molded, pumped up and sent -- all within one box.

Robert C. Gallagher once mused: "Change is inevitable -- except from a vending machine." Audio processors are no exception. DSP advances give processor designers access to ever-increasing power with no end in sight. Like most radio stations, we change processors within reason to remain competitive and to deliver a cleaner more listenable sound to our audience. This too is the goal among processing manufacturers. The full-blown audio processor has become a very complicated, albeit powerful unit where an engineer can find himself bogged down with literally hundreds of controls and options.

The Omnia One is not such a processor. It is designed to lower cost, guesswork, confusion and space requirements. It also offers itself to a variety of applications. The Omnia One can be used as a radio station's main processor: It includes an excellent stereo generator - the same one used in the Omnia 5EX and 6EX, an SCA/RDS input, a distortion cancelled final clipper, and so says Omnia, "the same processing topology that made the original Omnia FM famous."

Flexibility built in

The One is incredibly versatile. It can be used as a main processor for AM or FM, as an adjunct to a full-feature box, as a studio processor, a multicast processor, or a Web stream processor. It even offers a different firmware load for each such application. Should you decide to repurpose your One, simply download the firmware file for the flavor you now need.

I've chosen to use my processor for yet another task. Arbitron's PPM system offers new challenges to programmers and engineers alike. Of primary concern is the need to present the PPM encoder with an audio signal that is full and consistent. Since my main processors do not have a side-chain I/O where the PPM encoder could be inserted after the AGC, I needed to add something completely separate ahead of the PPM encoder. What I needed was simple audio consistency so I considered many of the old standbys -- the UREI, the Aphex, 8200ST and even the old CBS Volumax 410 crossed my mind. Of course none of those would work in this application because our audio chain is entirely AES digital. Furthermore, to use one of those units, I'd also need to add a D/A-A/D converter. This was indeed the wrong approach. A search of the Internet turned up exactly zero modern studio style audio processors with AES-EBU I/O. What to do?

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