Streaming And Netcasting Applications; Using Optimod 6300 In Streaming Applications; Loudness; Choosing Your Encoder - Orban OPTIMOD 6300 Operating Manual

OPTIMOD 6300 DIGITAL

Streaming and Netcasting Applications

This section was written in mid 2009. As the state of the art in netcasting is changing
with ferocious rapidity, we expect it to become outdated quickly. Please check
Orban's web site, www.orban.com, for newer information.

Using OPTIMOD 6300 in Streaming Applications

You need an audio source connection (either analog, AES3 digital, or SPDIF digital).
The digital input can accept any sample rate from 20 to 96 kHz. You can also use any
stream available within the computer's internal WAVE audio system, such as a digital
playout system. If you use the computer's WAVE audio system, you will need a sound
card with full duplex capability and digital inputs and outputs. Connect the digital
output of the sound card to the 6300's digital input and connect the 6300's digital
output to the input of the sound card.
You will ordinarily connect the signal that the sound card receives to the input of an
encoder application, like Orban's Opticodec-PC, Microsoft Windows Media Encoder,
Apple QuickTime® Broadcaster, or RealNetworks' Real/Helix Producer. You then ap-
ply the encoded output of the encoder to a netcast server application, which may
operate on the same machine as the encoder, or on a different machine on your
network. In the latter case, you will route the encoded audio to the netcast server
application through your network.
See Processing for Low Bit Rate Codecs on page 3-5.

Loudness

You can expect a significant increase in loudness from OPTIMOD 6300 processing by
comparison to most unprocessed audio.
An exception is recently mastered CDs, which may have already been ag-
gressively processed for loudness when they were mastered.
In radio broadcasting, it is generally believed that loudness relative to other stations
attracts an audience that perceives the station as being more powerful than its
competition. We expect that the same subliminal psychology will also hold true in
netcasting.

Choosing your Encoder

The state of the art in encoder technology is rapidly changing. At this writing, the
best audio encoder technology available is MPEG HE-AACv2, also known by its
trademarked name of AAC/aacPlus v2. Orban is the first provider of this technology
for streaming audio applications with Opticodec-PC. Opticodec-PC can provide en-
tertainment-quality stereo streams at 32 kbps. At 48 kbps, many listeners prefer the
sound to that of FM.
Be aware that different encoders are optimized for different bit rates, and you
should match your encoder to your potential audience. An encoder appropriate for
a dial-up rate of 20kb/sec may not be optimum for ISDN, DSL, or E-1/T-1 rates. This
makes it necessary to use more than one algorithm to optimally serve audiences
with these disparate connection speeds.
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INTRODUCTION