Perreaux Radiance R200i, Руководство пользователя

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Balanced
Interconnects
The use of the high quality Perreaux balanced signal inputs and outputs can
have the effect of cleaning up hums, buzzes, radio frequency interference
(RFI) and general extraneous rubbish that can enter an audio system. A
balanced signal input system operates on the principle of differential
amplification. The positive and negative inputs are contrasted against one
another and the difference between them is amplified. Noise entering the
system is imposed equally on the positive and negative signals and
therefore will not be amplified, as no differential voltage exists.
The term used to describe the quality of the effect is called Common Mode
Rejection Ratio (CMRR). CMRR is an equipment and system
specification, which describes how well unwanted common mode signals
are counteracted when used in conjunction with balanced connections.
CMRR action prevents the egress and build up of extraneous hum; buzzes
and RFI when analogue signals are conveyed down cables and between
equipment powered from different locations and is widely used in
professional audio applications.
The rejection ration achieved is described in minus dB. The CMRR of a
system follows the formula 20Log(V
output
/V
input
). In other words a CMRR
of –40dB means that all garbage entering the unit will be made 100 times
smaller. The piece of equipment with poorest CMRR will effectively
determine the hum and RFI level of the system. Effectively the weakest
link in the chain. Highest quality audio systems should quote a CMRR
figure of –80dB or better.
For optimal listening pleasure, we recommend using balanced signal inputs
Positioning
Ancillary
Equipment
Positioning of your source equipment (tuner, video, disc, tape, record,
decks) is important. To avoid airborne frequency peaks, place them well
away from your loudspeakers and not in the corners of your listening area.
Loudspeaker
Placement
Loudspeaker placement is a controversial issue; suffice to say that room
corners are generally the worst situation. Everything which constitutes
your listening area, including the materials used in its construction, will
affect the sound itself and the sound stage created. Equally, you have to
live with your system and therefore compromises will have to be made in
line with your particular priorities. The best advice we can give
concerning the choice of loudspeakers is, establish clearly in your mind
your requirements; listen to many makes and models, and if at all possible
audition your preferred choice in your own listening area and trust your
own ears.