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Streaming
A technique for transferring data such that it
can be processed as a steady and continuous
stream. Streaming technologies are often used
on the Internet because many users do not
have fast enough access to download large
multimedia files quickly, so the client browser or
plug-in can start displaying the data before the
entire file has been transmitted.
Subwoofer
The extra-low frequency drive-unit
(loudspeaker) that can be used to augment
both stereo and surround system.
T
Treble
High frequencies at the top end of the audio
band i.e. above 3kHz.
Tweeter
The drive unit (loudspeaker) that reproduces
high frequency sounds.
U
UPnP (Universal Plug and Play)
Universal Plug and Play is a networking
architecture developed by a consortium of
companies to ensure easy connectivity between
products from different vendors. UPnP devices
should be able to connect to a network
automatically, handling identification and other
processes on the fly. The standards developed
by the UPnP Forum are media-, platform-, and
device-independent.
USB (universal serial bus)
A hardware interface used to connect devices
such as computer audio players, digital cameras,
and more. USB is UPnP enabled (also called
hot-swappable), meaning that a computer does
not need to be turned off when new devices
are plugged in and the devices do not need to
be configured. USB supports data transfer rates
of up to 60MB per second (in USB 2.0).
S
S/PDIF (SPDIF) (Sony/Philips Digital Interface)
A standard audio-file transfer-format that was
developed jointly by Sony and Philips. S/PDIF
allows the transfer of digital audio signals from
one device to another, without the need to
convert first to analog. This prevents the quality
of the digital signal degrading during transfer to
analog.
Sampling rate
The precision with which a digital file describes
the analog sound it represents. Basically, a lower
rate produces files that sound worse and take
up less drive space than those with a higher
rate. CDs have a sampling rate of 44.1kHz,
and DAT machines have a sampling rate of
48kHz. MiniDisc player/recorders with a built-in
sampling rate converter can handle both rates.
Sensitivity
Volume that a speaker offers for a specific
voltage input, expressed in decibels per watt
(dB/W).
Shuffle
A feature that plays audio files (tracks) in
random order.
Signal to noise ratio
Represents the difference between the level of
the audio signal, and any interference. The larger
the figure, the purer the sound.
SPL (sound pressure level)
An acoustic measurement of sound energy.
1 dB SPL is the smallest increment in sound
level to which the average human is sensitive.
Theoretically, 0 dB SPL is the threshold of
human hearing while approximately 120 dB is
the threshold of pain.
Stereo
Literally means solid. Usually taken to refer to
two channel stereo, though developments in
digital audio facilitate multichannel stereo.
EN