HD audio for background music distribution

Distribution of HD Audio to ENA Amplifiers

Background music is distributed by using the Audio Program feature of the ICX-AlphaCom. By default this feature is using the HD Voice codec G.722.

In installations where an even better audio quality for background music distribution over the PA system is required, it is possible to use the HD Audio codec PCM L16/48kHz.

The following devices support audio input feed using the PCM L16/48kHz codec:

• ENA Amplifier
• TKIE-2 kit

The following devices can play (listen to) audio in PCM L16/48kHz format:

• ENA Amplifiers (ENA2200, ENA2400-AC, ENA2400-DC and ENA-2100)
• Turbine kits (TKIE-1, TKIE-2 and TKIS-2)
• IP Speakers (ELSII-10H and ELSIR-10C)

The HD Audio stream is not going via the ICX-AlphaCom, the ICX-AlphaCom does not support this format. Only the signalling protocol is controlled by the ICX-AlphaCom. Stations that don't support HD Audio will resample to the supported sample rate. Although the "HD Audio" option is available in all Turbine devices ("Voice Engine Mode"), the echo cancelling is disabled when enabling "HD Audio". Hence the station will not be suitable for two-way communication. The "HD Audio" option is intended for Turbine kits used as PA Interfaces.

Requirements

Software
HD Audio is supported from:

• ICX-AlphaCom: 1.0.3.0
• AlphaCom XE: 12.5.3.1
• Intercom device: 4.9.3.0

License:

• HD Audio for background music distribution requires a High bandwidth audio license. It is sufficient with one HD Audio license per ICX-AlphaCom server.
• If the Audio Input source is the Line Input of the ENA Amplifier, one ENA Amplifier Channel License is required
• To install the license, log on to the web interface of the ICX-AlphaCom server, and select System Configuration > Licensing.

Audio Source Configuration

TKIE-2 as Audio Source

Log in to the web interface of the TKIE kit, and enable Advanced Configuration in the top right corner of the web interface.

Enable Line In:
To use the TKIE-kit as Audio Program source, enable Line In. A reboot of the TKIE kit is required for the change to take effect:

Enable Line In on the TKIE kit

Disable AGC (Automatic Gain Control):

Disable AGC

Set Audio Engine Mode = HD-Audio:

Enable HD-Audio

ENA Amplifier as Audio Source

The Line In on an ENA amplifier can be used as Audio Program Source.

• Log In to the amplifier
• In Main > Main Settings enter a directory number to use for the Line Input:

Enter a directory number to use for the Line Input

Configuration of ICX-AlphaCom server

The "HD Audio" is transmitted from the Audio Source as Multicast data in the network. The ICX-AlphaCom must be configured to use Multicast for group audio.

In AlphaPro, Exchange & System > System > VoIP tab, enable Multicast:

Enable Multicast in ICX-AlphaCom

The Line Input channel of the ENA Amplifier (or the TKIE-2 kit) must register to a directory number in the ICX-AlphaCom server.

In AlphaPro, Users & Stations, enter a directory number for the Line Input and set the Noise Reduction to 0:

Define a Directory Number for the Audio Program Source

Create a feature code to become an Audio Source. From AlphaPro Directory & Features, press Insert and create a new directory number:

• Feature 118 - Program Source
• ID (Parameter 1) = Program channel 1-70
• Parameter 2 = Group index 1- 255. Chooose a group which is not in use. Important: At least one station must be included in this "dummy" group.
• Parameter 3 = 10 (PCM L16/48kHz codec)

The example below shows how to add directory number 6801 as the code to become the source of Audio Program #1.

A device dialing 6801 will become the source for Audio Program 1 (ID = Program channel). A station must be included in group 100.

The station added to the group doesn't have to be a real station, simply pick any unused station. Do not add an IP Dummy to the group, as it will prohibit the HD Audio setup.

A station/device dialing feature 118 becomes the program feeder. Add an event that sets the Audio Program Source as source for program feed. Use the event 13 (Faulty Station), When Change To = OFF, and action: $DD L%1.dir L6801.

The Audio Program Source dials 6801 after registration, and becomes the source for program #1

The Audio Program Source must be allowed access to feature 118. To avoid any other station/device dialing the directory number for the feature, it is advisable to define a separate COS for this feature. Add feature 118 to this Class of Service (CoS #2 in the example below).

Make feature 118 "valid" in Class of Service 2

Assign the Audio Program Source to the Class of Service:

Setting Class of Service 2 for the Audio Program Source

The Directory numbers used to listen to program are the default numbers 801 - 806. The directory number for feature 118 (e.g. 6801) is NOT for listening, but used to set the source for the program channel. In AlphaCom XE20/26, do not use feature 118 for Audio Program channel 1-6, as these channels are reserved. In AlphaCom XE7, do not use feature 118 for Audio Program channel 5 and 6, as these channels are reserved.

Using Audio Programs

• Audio Program selection
• Remote setup to other stations or groups/zones