Yealink T27P Administrator's Guide

Configuring Audio Features
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Background noise suppression (BNS) is designed primarily for hands-free operation and
reduces background noise to enhance communication in noisy environments.
Automatic Gain Control (AGC) is applicable to hands-free operation and is used to
keep audio output at nearly a constant level by adjusting the gain of signals in certain
circumstances. This increases the effective user-phone radius and helps with the
intelligibility of talkers.
Voice Activity Detection (VAD) is used in speech processing to detect the presence or
absence of human speech. When detecting period of “silence”, VAD replaces that
silence efficiently with special packets that indicate silence is occurring. It can facilitate
speech processing, and deactivate some processes during non-speech section of an
audio session. VAD can avoid unnecessary coding or transmission of silence packets in
VoIP applications, saving on computation and network bandwidth.
Procedure
VAD can be configured using the configuration files or locally.
Configuration File
<y0000000000xx>.cfg
Configure VAD.
Parameter:
voice.vad
Local
Web User Interface
Configure VAD.
Navigate to:
http://<phoneIPAddress>/
servlet?p=settings-voice&
q=load
Details of the Configuration Parameter:
Parameter
Permitted Values
Default
voice.vad
0 or 1
0
Description:
Enables or disables VAD (Voice Activity Detection) feature on the IP phone.

Yealink T27P Specifications

General

Wall Mountable	Yes
Local Phonebook	1000 entries
Bluetooth	No
Wi-Fi	No
Gigabit Ethernet	No
Display	3.66" 240x120 pixel graphical LCD with backlight
Audio Features	HD voice, Full-duplex speakerphone
Network	Dual-port 10/100 Ethernet switch
Protocols	SIP v1 (RFC2543), v2 (RFC3261)
Power	IEEE 802.3af PoE
Connectivity	2 x RJ45 10/100M Ethernet ports
Voice Codecs	G.711(A/μ), G.722, G.723, G.729AB, G.726
EHS	Supports EHS with Plantronics headsets
Headset Port	Yes
Power Adapter	5V DC (optional)