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HPA-DAC8
Owner’s Manual
AtlasIED.com
TELEPHONE: (800) 876-3333
1601 JACK MCKAY BLVD.
ENNIS, TEXAS 75119 U.S.A.
Dante
®
Items to Know or Think About
1. Fixed Levels - Signal level cannot be added or reduced within Dante
®
Controller. It is
strictly a signal router.
2. What Does 0dBFS Mean - 0dBFS is defined as decibels relative to full scale. It is the
maximum amplitude levels in digital systems before clipping. Each digital product has
there own specific maximum amplitude levels. When interfacing Dante networks, it is
very important to know the source and receiver 0dBFS specification to prevent system
clipping.
3. Industry Standard - At the time of this information, there is no industry standard
between companies for scaling 0dBFS gain levels in equipment. In a digital studio
this is usually not an issue because most of the same brand is used or a limited
number of products are interfaced. However, with live sound or commercial audio
there can be multiple brands used in one job. Dante
®
can be great for reliable
connectivity between devices but be aware of gain structure
4. Interfacing Data with Different Manufacturers’ Equipment - To help understand scaling
here are some examples:
• Source device 0dBFS = 20dBu, transmits to a receiver with a 0dBFS = 20dBu
reference, the output is 0dBu. This scenario is ideal when using the HPA amplifiers.
• Source device 0dBFS = 20dBu, transmits to a receiver with a 0dBFS = 10dBu
reference, the output is -10dBu. To get full output of the HPA amplifiers you have to
increase the network output levels by 10dBu to get 0dBu into the HPA amplifiers
input.
• Source device 0dBFS = 10dBu, transmits to a receiver with a 0dBFS = 20dBu
reference, the output is +10dBu. This combination will give too much signal into the
HPA amplifier. Reduce the signal from the DSP network output.
• Source device 0dBFS = 10dBu, transmits to a receiver with a 0dBFS = 10dBu
reference, the output is 0dBu. This scenario is ideal when using amplifiers with
0.775V input sensitivity.
5. Understanding Digital Noise vs Headroom - If headroom before clipping is a concern,
the higher the ratio between 0dBFS and output level, the less likely clipping will be an
issue. If the application is paging and background music, then a lower ratio is ok
because the headroom is not as critical. In live sound reinforcement applications
such as a church band or a concert, more headroom and gain is needed for dynamics.
It’s important to note that the higher the gain the higher the noise output. To combat
high gain output noise, use a Dante
®
transmitter product with good signal to noise
ratio specification, such as 100dB or better. For instance, AtlasIED BlueBridge
®
DSP
has a signal to noise ratio of 110dB. The noise is very low before it is amplified,
assuring low noise out of the HPA amplifier. Look at the input and output 0dBFs
reference points and the noise floor specification. If they are not listed call the
manufacturer.
