Set Up Wideband Codec - Cisco 7821 Administration Manual

</CiscoIPPhoneRingList>
The PCM files for the rings must meet the following requirements for proper playback on Cisco IP Phones:
• Raw PCM (no header)
• 8000 samples per second
• 8 bits per sample
• Mu-law compression
• Maximum ring size = 16080 samples
• Minimum ring size = 240 samples
• Number of samples in the ring = multiple of 240.
• Ring start and end at zero crossing.
To create PCM files for custom phone rings, use any standard audio editing package that supports these file
format requirements.

Set Up Wideband Codec

By default, the G.722 codec is enabled for the Cisco IP Phone 7821, 7841, and 7861. If Cisco Unified
Communications Manager is configured to use G.722 and if the far endpoint supports G.722, the call connects
using the G.722 codec in place of G.711.
This situation occurs regardless of whether the user has enabled a wideband headset or wideband handset,
but if either the headset or handset is enabled, the user may notice greater audio sensitivity during the call.
Greater sensitivity means improved audio clarity but also means that the far endpoint can hear more background
noise: noise such as rustling papers or nearby conversations. Even without a wideband headset or handset,
some users may prefer the additional sensitivity of G.722 distracting. Other users may prefer the additional
sensitivity of G.722.
The Advertise G.722 Codec service parameter affects whether wideband support exists for all devices that
register with this Cisco Unified Communications Manager server or for a specific phone, depending on the
Cisco Unified Communications Manager Administration window where the parameter is configured:
Procedure
Step 1
Step 2
<Ring>
<DisplayName>Analog Synth 2</DisplayName>
<FileName>Analog2.raw</FileName>
</Ring>
Command or Action
To enable wideband support for all phones, perform the following steps:
To enable wideband support for a specific phone, perform the following
steps:
Cisco IP Phone 7821, 7841, and 7861 Administration Guide for Cisco Unified Communications Manager 10.0 (SIP)
Set Up Wideband Codec
Purpose
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