View source for HD audio for background music distribution

{{A}} [[File:ENA HD Audio.png|thumb|right|600px|Distribution of HD Audio to ENA Amplifiers]]
Background music is distributed by using the [[Audio Program|Audio Program feature]] of 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|TKIE-2 kit]]

The following devices can play (listen to) audio in PCM L16/48kHz format:
* ENA Amplifiers ([[ENA2200 Amplifier|ENA2200]], [[ENA2400-AC Amplifier|ENA2400-AC]], [[ENA2400-DC Amplifier|ENA2400-DC]] and [[ENA2100-AC Amplifier|ENA-2100]])
* Turbine kits ([[TKIE-1]], [[TKIE-2]] and [[TKIS-2]])
* IP Speakers ([[ELSII-10H]] and [[ELSIR-10C]])




{{Note|
* ''The HD Audio stream is not going via the AlphaCom, the AlphaCom does not support this format. Only the signalling protocol is controlled by the AlphaCom.'' 
* ''Stations that doesn't support HD Audio will not receive any audio.'' 
* ''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'''<br>
HD Audio is supported from: 
* AMC 12.5.3.1
* Turbine 4.9.3.0

'''License''': 
* '''HD Audio''' for background music distribution requires a [[Licenses#High_bandwidth_audio_license|High bandwidth audio license]]. It is sufficient with one HD Audio license per AlphaCom server.
* If the Audio Input source is the Line Input of the ENA Amplifier, one [[Licenses#Exigo_.28ENA.29_Amplifier_license|ENA Amplifier Channel License]] is required 
* To install the license, [[AlphaWeb#AlphaWeb_Login|log on to the web interface]] of the AlphaCom server, and select '''System Configuration''' > '''Licensing'''.

== Configuration ==
=== Configuration of ENA Amplifier ===
*[[Logging into an IP Station|Log In to the amplifier]]
* In '''Station Main > Main Settings''' enter a directory number to use for the Line Input:

[[File:ENA Audio In.png|thumb|left|500px|Enter a directory number to use for the Line Input]]
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* '''Enable the Line Input''': In [[ENA_Configuration_-_AlphaCom_mode#Line_Control|Amplifier Settings > Line Control > Line In]] section, set '''Line In Type''' = "Line Input", and set Impedance to High or 600 ohms (most common).

=== Configuration of TKIE-2 ===

If a TKIE is used as Audio Program source, '''Audio Input Source''' must be set to "Line In". Disable AGC as well.:

[[File:Line_In.PNG|thumb|left|500px|Set "Audio Input Source" = Line In]]
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=== Configuration of AlphaCom server ===
The "HD Audio" is transmitted from the Audio Source as Multicast data in the network. AlphaCom must be configured to use Multicast for group audio.

In AlphaPro, '''Exchange & System''' > '''System''' > '''VoIP''' tab, enable '''Multicast''':
[[File:AP Enable Multicast.png|thumb|left|500px|Enable Multicast in AlphaCom]]
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The Line Input channel of the ENA Amplifier (or the TKIE-2 kit) must register to a directory number in the AlphaCom server.

In AlphaPro, '''Users & Stations''', enter a directory number for the Line Input and set the Noise Reduction to 0:
[[File:HD Audio1.png|thumb|left|500px|Create a Directory Number for "Line Input"]]
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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|Program Source]]
* ID (Parameter 1) = Program channel 1-70
* Parameter 2 = Group index 1- 255. Chooose a group which is not in use. At least one station must be included in this "dummy" group. It doesn't have to be a "real" station, a non-existent station can be included.
* 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. 

[[File:Feature 118.png|thumb|left|500px|A device dialing 6801 will become the source for Audio Program 1 (ID = Program channel). A "dummy" station must be included in group 100]]
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A station/device dialing feature 118 becomes the program feeder. Add an event that sets the Line Input of the ENA Amplifier (or TKIE-2) as audio program source. Use the event 13 (Faulty Station), When Change To = OFF, and action: ''$DD L%1.dir L6801''.

[[File:ENA LineIn Prog1.PNG|thumb|left|500px|The ENA Line Input dials 6801 after registration, and becomes the source for program #1]]
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The station/device appointed as program feed must be allowed to access feature 118. Add feature 118 to the Class fo Service group the station/device is belonging to. 
[[File:AudioSourceCOS.png|thumb|left|500px|Adding feature 118 to Class of Service 1]]
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To avoid any other station/device dialling the directory number for the feature, it is advisable to define it in a separate COS.
[[File:AudioSourceCOS2.png|thumb|left|500px|Setting Class of Service 2 for the audio source station/device]]
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{{Note|
* ''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.'' }}
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== Using Audio Programs ==
* [[Audio_Program#Audio_Program_selection|Audio Program selection]]
* [[Audio_Program#Remote_set-up_of_Audio_Program|Remote setup to other stations or groups/zones]]


[[Category: Public Address - Features and configuration]]