GLOSSARY
5.1 or AC-3
5.1-multichannel encoding means that 5 audio channels with full frequency response are
present (left, center, right, surround left, surround right) plus a subwoofer channel
(represented by the „.1‖) providing deep humming frequencies you are used to know from
modern cinemas. Both Dolby Digital® and DTS® support 5.1-coding and
–decoding.
Aspect ratio: 4:3 and 16:9
Full Frame refers to programs developed for TV display with an aspect ratio of 4:3.
Widescreen refers to programs developed for screens with an aspect ratio of 16:9.
If a widescreen program is displayed on a 4:3 screen, the picture will have black borders on
top and bottom.
CD
A CD (Compact Disc) is a metal-coated plastic disc. It has a diameter of 12 cm and a
thickness of about 1,2 mm. It was developed by Sony and Philips in 1985. The advantages
are digital storage of music enabling very natural sound reproduction. Beyond this, the data
is stored more compact, the handling is easy. The long lifetime of the media and the fact that
usage does not decrease quality made the CD the ideal storage media.
In the meantime, 12 different storage media have been developed from the first CD. The
mostly used are CD-DA (Compact Disc - Digital Audio) , CD-ROM (Compact Disc - Read
Only Memory), and the DVD (Digital Versatile Disc). One can store about 74 to 80 minutes
of music on a CD (-DA). This is equal to 650 to 700 MB.
Signal transmission is performed touchless with a laser beam. The CD is being read from the
middle to the outer side. The data or music is recorded in a spiral from the middle to the
outer side.
A CD has pits and lands, the distance is about 1,6 mm. The laser light created by a laser diode
passes different mirrors and prisms and then is focused by a lens to a laser beam.
This laser beam scans the data spiral of the CD. On the pits, the laser beam is reflected in
another direction and is detected by a photocell. The photocell transmits the signal to a
microprocessor, which converts the digital data to an audio signal. The rest is done by the
sound system.
Coaxial
Coaxial is a digital transmission standard for audio data transfer. Coaxial can transmit digital
audio tracks from one source to another without having to leave the digital transmission,
which would result in worse quality.
Contrast
Means the range of luminance between the brightest and the darkest pixel, which can be
displayed.
CVBS
Composite Video Interface. The video signal is transmitted via a single signal line. CVBS
should only be used, if your playback device does not offer other interfaces for connection
with you Xoro TV set, as CVBS due to technical reasons delivers worst quality of all
available interfaces (please also refer to YUV, S-Video, SCART and RGB). The CVBS
interface can easily be identified from the yellow colour of the RCA jack.
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