Prestige CANTERBURY SE, Руководство пользователя

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Loudspeakers need power signals to produce acoustic energy when reproducing music. The range of electrical currents passing down
the cable from the amplifier to the loudspeaker is very wide. In decibel terms this is called the dynamic range. Modern loudspeakers
are capable of resolving a dynamic range of at least 80dB with a suitable power amplifier.
An 80dB dynamic range corresponds to voltages of between 50 Volt and 0.005 Volt at the loudspeaker terminals or equivalent currents
of between 0.0006 and 6 Amp. This is a truly wide range of electrical signals to pass down one cable without some interactions causing
a loss of resolution in the very small signals.
When electricity passes down a wire or cable, what goes in at one end is unfortunately different from what comes out at the other.
The degree of loss or modification of a signal depends on the physical characteristics of the cable and the nature of the signal. Heavy
electrical currents flowing down thin conductors cause heating effects. Very high frequency signals passing along conductors or cables
of certain lengths cause electromagnetic radiation effects (aerials). Electrical cables are selected for minimum loss and maximum
information resolution considering the type of electrical signals they are designed to carry.
A good solution to the problem is to 'bi-wire' the loudspeakers to the amplifier. This means providing two separate sets of cables from
the power amplifier to each loudspeaker and dividing the electrical signals into high current, 'slow' signals and light current, 'fast' signals.
Of course, the loudspeaker must be fitted with two pairs of terminals to take the two sets of cables; your Tannoy loudspeakers are of
course equipped for just this type of connection.
Bi-Wiring Theory
Bi-wiring releases the full potential of the Tannoy Prestige loudspeakers. Two complete sets of cable are required.
Switch the amplifier off. Deal with each 'side' of the system separately.
Label two of the cables Left LF and Left HF (low frequency and high frequency). Do the same for the right pair. Undo the loudspeaker
terminals, remove and retain the Bi-wiring links so that the same polarity terminals are no longer joined.
It is essential to get the polarity correct. If your amplifier does not have separate output terminals for bass and treble then, at the amplifier
end of the cable, connect the Left LF+ and HF+ cables together. Then wire to the amplifier Left channel positive terminal
(plus) or coloured red.
Connect the Left LF - and HF - cables together to the amplifier negative terminal marked - (minus) or black.
Note the polarity marking on the cable. At the loudspeaker end connect the cables marked Left LF+ and LF- to the appropriate left
speaker LF terminals. Connect the Left HF+ and HF- to the appro and - left speaker HF terminals.
Make the same connections with the Right LF and HF cables.
For optimum performance, the earth connection on the terminal panel should be connected to the amplifier chassis earth or other
ground point. This screening effect can give an improvement in detail clarity, depending on the amplifier used. Optimum results are
achieved using a screened loudspeaker cable designed for such a system, such as the Tannoy TLC.
Switch on the amplifier with the volume turned down. Select a favourite source and carefully turn up the volume. Check that bass and
treble sounds come from both speakers. If not, switch off and remake the connections.
Bi-Wiring
High quality audio signals passing from power amplifier to loudspeaker are unusual in their demands on cable. Frequencies from 20Hz
to 20kHz (10 octaves or a ratio of 10,000:1) and currents of 80dB dynamic range (again a ratio of 10,000:1) have to coexist. The cable
also has to be capable of transmitting peak currents of at least 10 Amp without causing losses greater than 0.001 Amp (10 Amp divided
by the ratio 10,000).
These strict requirements on loudspeaker cables help explain why the sound quality from loudspeakers is so dependant on the physical
properties of the cables connecting them to the power amplifier.
Cables
FIG. 1
TERMINAL PANEL CONNECTIONS
HIGH FREQUENCY
PO) TERMINAL
'EARTH' OR 'GROUND' TERMINAL
LOW FREQUENCY
PO) TERMINAL
HIGH FREQUENCY
NEGATIVE(-) TERMINAL
LOW FREQUENCY
NEGATIVE(-) TERMINAL
HF+
HF
-
LF+
LF-
FIG. 2
SINGLE WIRE MODE AND EARTH (GROUND)
LEAD CONNECTION
TO RIGHT
SPEAKER
LINK WIRES IN PLACE
POWER AMPLIFIER
R
+ - -
L
+
TO 'GROUND' OR
'EARTH' CONNECTION
ON AMPLIFIER (OPTIONAL)
HF+
HF
-
LF+
LF-
FIG. 3
BI-WIRE MODE AND EARTH (GROUND)
LEAD CONNECTION
TO RIGHT
SPEAKER
- +
R
- +
L
POWER AMPLIFIER
LINK WIRES REMOVED
TO 'GROUND' OR
'EARTH' CONNECTION
ON AMPLIFIER (OPTIONAL)
HF+
HF
-
LF+
LF-
FIG. 4
BI-AMPING MODE AND EARTH (GROUND)
LEAD CONNECTION
- + -
R
+
L
R
- + - +
L
HIGH FREQUENCY
POWER AMPLIFIER
LOW FREQUENCY
POWER AMPLIFIER
LINK WIRES REMOVED
TO 'GROUND' OR
'EARTH' CONNECTION
ON HIGH FREQUENCY
AMPLIFIER (OPTIONAL)
TO RIGHT
SPEAKER
TO RIGHT
SPEAKER
HF+
HF
-
LF+
LF-