Audio Quality Subjective To User; Connecting A Headset - Cisco 3951 Administration Manual

Understanding the Cisco Unified IP Phone Components

Audio Quality Subjective to User

Connecting a Headset

Cisco Unified SIP Phone 3951 Administration Guide for Cisco Unified CallManager 5.1
3-6
Cisco Systems recommends the use of good quality external devices, like headsets
that are screened against unwanted radio frequency (RF) and audio frequency
(AF) signals. Depending on the quality of these devices and their proximity to
other devices such as cell phones and two-way radios, some audio noise may still
occur.
The primary reason that support of a headset would be inappropriate for an
installation is the potential for an audible hum. This hum can either be heard by
the remote party or by both the remote party and the Cisco Unified IP Phone user.
Some potential humming or buzzing sounds can be caused by a range of outside
sources, for example, electric lights, being near electric motors, large PC
monitors. In some cases, a hum experienced by a user may be reduced or
eliminated by using the Cisco Unified IP Phone Power Cube 3
(CP-PWR-CUBE-3).
Beyond the physical, mechanical and technical performance, the audio portion of
a headset must sound good to the user and the party on the far end. Sound is
subjective and Cisco cannot guarantee the performance of any headsets or
handsets, but some of the headsets and handsets on the sites listed below have
been reported to perform well on Cisco Unified IP Phones.
Nevertheless, it is ultimately still the customer's responsibility to test this
equipment in their own environment to determine suitable performance.
To connect a headset to the Cisco Unified SIP Phone 3951, plug it into the RJ-9
Handset port on the back of the phone. Depending on headset manufacturer's
recommendations, an external amplifier may be required. Refer to headset
manufacturer's product documentation for details.
You can use the headset with all of the features on the Cisco Unified IP Phone,
including using the Volume button.
Chapter 3 Setting Up the Cisco Unified IP Phone
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