Owner’s Manual
HPA-DAC4
Dante
®
Accessory Card
AtlasIED.com
– 9 –
Specifications are subject to change without notice.
1601 Jack McKay Blvd. • Ennis, Texas 75119 U.S.A.
Telephone: 800.876.3333 • Fax: 800.765.3435
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
- In the previous example, the signal output of the BlueBridge
®
DSP
onto the Dante
®
network is 0dBu, so the signal within the BlueBridge
®
DSP can be increased by
20dBu before clipping the Dante
®
network. This defines the relationship of 0dBFS = 20dBu
(0dB “Full Scale”) from the source, which in this case the source is the BlueBridge
®
DSP.
When interfacing Dante
®
networks, it is very important to know the source and receiver OdBFS
specification.
3.
HPA-DAC4, -10dB Setting
- If the setup is identical as described above, but the HPA-DAC4 card is
set to 0dBFS = 10dBu, how would that affect a HPA amplifier? The signal coming into the HPA
amp would be -10dB down and the amp could never reach full output because the HPA amplifier
requires 0dBu to reach full output power. To correct the low input level to the amp, increase the
signal from the source (BlueBridge
®
DSP) by 10dBu. Keep in mind within BlueBridge
®
there is only
10dBu of headroom before digitally clipping the input of the HPA-DAC4. Be careful when adding
EQ boost. If adding 6dB of EQ boost at 100Hz, there is only 4dB of headroom at 100Hz before
clipping. If the HPA-DAC4 was set to 20dBu = 0dFS there would be 14dB of headroom at 100Hz.
This is why it’s so important to know the OdBFS reference points between devices in the Dante
®
network.
4.
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 connectivity between devices but be aware of gain structure matching.
5.
Interfacing Data with Different Manufactures 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 .775V input sensitivity.
