Omnia Audio Omnia A/XE - Manual (Page 7)

1
Introduction
The audio industry employs dynamics signal processing for many aspects within a broadcast
station, recording studio, mastering facility, and numerous other requirements. From simple
compression of a microphone channel, to special desired effects in the production studio,
and on through the creation of dial-dominance in the transmission path, processing has al-
ways been hardware-based. Even with the evolution of digital signal processing (DSP), most
processors are still physical boxes that engineers, producers, and program directors tweak as
they desire to achieve that signature sound. But where is it all headed as technology moves
into more of a software-based world? The personal computer has revolutionized our culture,
and it now can provide us with the required machine cycles of power to accomplish many of
the tasks we ask DSP chips to perform.
We introduce to you to Omnia A/XE a versatile audio processing and encoding platform
that is available as a pure software utility! Our Omnia processors dominate the airwaves the
world over. The products that have helped us achieve this success are based upon innovative
ideas in the area of dynamics audio processing and Omnia A/XE brings these ideas to your
PC.
Omnia A/XE offers what other rack mountable, or PC based hard-card products do, but it
doesn’t require the overhead of these other products. It makes use of the increased process-
ing power available inside today’s faster PC’s. Off the shelf PC’s now contain more than
enough power to perform audio dynamics processing and encoding, serving up multiple
processed and encoded streams from within a single computer or web-server.
Motivation
There are thousands of Internet radio-station-like audio webcasters. Like their over-the-air
counterparts, these can all benefit from dynamics processing. Every radio station uses audio
processing and there is no reason to believe that webcasters wouldn’t want it, too. Television
stations also employ processing, just as Internet video services will, as they grow in sophisti-
cation.
The growing power of PCs makes it possible to have multiple audio processors and encoders
on one PC. As network bandwidth increases, there will likely be more webcasters entering
the fray – and more concern about audio quality as these services become more mainstream.
Effective processing divides audio into multiple frequency bands and dynamically adjusts
levels to be optimum for the following transmission medium. On the surface, this is a
simple function. But to get the sound appropriately optimized without adding or ag-
gravating undesirable codec “artifacts” is a tricky blend of art and science involving many
trade-offs. Expert ears coupled with audio design expertise are required to get this work
accomplished – and these are rare combined skills.
Transmitting audio on the Internet requires bitrate compression (data reduction). Uncom-
pressed stereo audio would require 25x more capacity than possible over a 56kbps modem
connection. Even broadband connections require compression so that the audio doesn’t take