Technical information

connected to the shaft. These appear in some very high quality turntables and
offer particular advantages of high acceleration to speed, plus electronic speed
control and stability.
Tweak A subtle change to home audio or A/V intended to improve the sound.
This could range from merely adjusting the system's controls, through replacing
cables and experimenting with speaker positions, to all kinds of damping and
isolating procedures.
Tweeter A small speaker driver designed to produce high frequency (or treble)
sounds. This typically operates from 2,000 to 6,000 hertz, depending on the
other drivers, up to and sometimes beyond the limits of human hearing at 20,000
hertz. The deeper notes are routed by a crossover network to the midrange
driver (if any) and woofer.
Two-way loudspeakers A loudspeaker which divides the incoming signal into two
different frequency bands for distribution to drivers. It sends high frequencies to
the tweeter and low frequencies to one or more woofers.
U, V
Ultrasonic Audio tones of frequencies higher than capable of being detected by
the human ear, generally above 20,000 hertz.
VBR Variable bit rate as opposed to CBR or constant bit rate. The flow of digital
data increases or slows over time, according to the complexity of the encoded
signal. Has the advantage of allocating more of the scarce data space to those
moments of video or audio that most need it, while economizing on sections that
can get by with less data.
VCD Video CD. A movie format popular in Asia in which highly compressed
movies can be placed on an optical disc adhering to CD conventions. MPEG-1
compression is used, which is less effective than the MPEG-2 used on DVDs.
Because of the data size limitations of CDs, VCD movies are of much lower
resolution than DVDs and are usually spread over at least two VCDs.
VCR Video Cassette Recorder. The analogue video recording system using tapes
in a robust plastic housing. Superseded by the DVD.
VHS Video Home System. A consumer-level video recording system developed by
JVC in the late 1970s. Despite urban legends to the contrary, it was not
noticably inferior to Sony's Beta system (although the latter offered a slightly