T+A Elektroakustik P 10 - Handbuch (Seite 38)

Glossary
AUX
Universal pre-amplifier input (AUX = auxiliary input) for
connecting high-level signal sources (i.e. signal sources
with an output level between 0.25 V and 4 V).
Balance
The balance control provides infinite adjustment of level
between right and left channels (shift of stereo centre),
e. g. to compensate for asymmetric speaker positioning.
To avoid any adverse effect on the sound, the balance
range is limited to +6 dB. It is never desirable to reduce
the volume of one stereo channel to zero.
dB
The unit of measurement for electrical levels is the deci
Bel (dB).
Loudness
A volume-dependent tone control (Loudness) circuit
which compensates for the frequency-dependent sensi-
tivity of the human ear at very low volume levels. At very
high volumes the loudness circuit has absolutely no
effect, but as volume is reduced the bass and upper
treble are lifted, in order to compensate for the reduction
in sensitivity of the human auditory system at low levels.
MC
Some analogue turntables are fitted with dynamic sound
pick-up systems (MC = Moving Coil). The amplifier can
be fitted with an optional high-quality MC phono pre-
amplifier module whose input impedance and input sen-
sitivity can be adjusted to match all currently available
dynamic pick-up systems.
MM
Some analogue turntables are fitted with magnetic sound
pick-up systems (MM = Moving Magnet). The amplifier
can be fitted with an optional high-quality MM phono pre-
amplifier module whose input impedance and input
sensitivity can be adjusted to match all currently available
magnetic pick-up systems.
R LINK
Control interface for remote control of  source
devices, surround decoders and output stages. The pre-
amplifier receives the remote control signals and passes
them to the currently selected source device via this
interface.
Source device
The term source device refers to those elements of a Hi-
Fi system which provide a sound signal, such as tuners,
CD players, recorders etc. (signal sources). We have to
differentiate between listening sources and recording
sources.
• A listening source is the device to which you are
currently listening. This device can be remote-
controlled.
• A recording source is a source from which a recording
can be made using a recorder (TAPE). A recording
source cannot be remote-controlled.
Surround
Some signal sources (e.g. DVD or digital TV) supply
multi-channel sound using the DOLBY or dts standard.
Your
 stereo amplifier can be expanded with a
supplementary decoder to form a high-quality multi-
channel Hi-Fi surround system. Please ask your specia-
list
 dealer for advice; he will gladly advise you con-
cerning multi-channel technology.
Symmetrical outputs (XLR)
The principle of symmetrical connections has its origins
in studio technology, where the highest possible quality
and best possible interference suppression are required.
The principle is based on the idea of transferring two
mirror-image (inverted) signals instead of a single signal.
The receiving device generates the difference signal
between these two signals, with the effect that all traces
of interference are eliminated, and only the pure, un-
coloured signal remains for further processing. Of course,
symmetrical signal transfer is of particular interest where
large distances are involved, e. g. with active speakers,
or where the audiophile listener wishes to set up the
power amplifiers directly adjacent to the speakers in
order to keep the critical loudspeaker cables as short as
possible.
However, symmetrical amplifier technology offers further
advantages: no currents are transferred via the earth
conductor, which would otherwise result in a decline in
earth voltage, which would in turn offset the vitally im-
portant earth reference potential. Since the amplitude of
the effective signal is doubled by the difference genera-
tion process, the voltage amplitude per unit of time is also
doubled, thereby doubling the slew rate of the signal.
An additional advantage is that distortion and background
noise tend to cancel each other out. The improvement in
noise is around 3 dB, which equates to a reduction in
hiss of around 30 %. Fact: symmetrical signal technology
does require considerably greater complexity, since
some parts of the amplifier have to be duplicated, but in
our opinion the gain in fidelity justifies the effort every
time.
The external sign of the extra investment we have made
in this technology is the presence of indestructible, pro-
fessional studio XLR sockets.
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