Instruction manual

30 UltraLink 2 DVI Installation and Operation Manual
Sound Control
The Sound Control menu item provides options to control the quality of transmitted audio. As in the case of the
video settings, a trade-off exists between having better sound quality and the network bandwidth required to
transmit the audio.
As previously stated in the Installation section, only the RealVNC Viewer downloaded from the UL2-DVI
provides audio support. Audio support is not present on Viewers downloaded from the RealVNC website.
Figure 42. Sound Control Screen
The options in the Sound Control screen are described below.
Format – uLaw, Linear:
The options in the Format field specify the format of the audio signals being transmitted over the network. The
uLaw format transmits the audio signals as 8-bit compressed data, which aids in faster transmission over the
network. The Linear format sends the audio signals as 16-bit uncompressed or raw data, giving better sound
quality. The uLaw format is recommended for slow networks, since less data is being sent. The Linear format
is preferred for fast networks since better sound quality is to be had.
Sample rate – 8000, 48000:
Sample rate is the number of times the audio is sampled per second. 8000 Hz means the audio is sampled
less frequently, and is preferred for slower networks. 48000 Hz means the audio is sampled more frequently.
This provides better sound quality, but increases network traffic, and is more suitable for fast networks.
Channels – Mono, Stereo:
The Channels option allows selecting between Mono and Stereo audio. Mono is preferred for slower networks.
Stereo gives better sound quality on fast networks.
Window size(ms):
The Window Size(ms) option specifies the length of time in milliseconds that the UL2-DVI will wait after
sending an audio packet to the VNC Viewer for the Viewer to acknowledge receipt of the packet. If no
acknowledgement is received by the UL2-DVI within that length of time, the unit stops transmission of further
audio packets.