T+A Elektroakustik Criterion TL 500, Руководство пользователя

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Amplifier recommendations
Your  loudspeakers can be driven by
any amplifier designed to handle a load
impedance of 4 Ohms. If the speakers are
to be connected to an amplifier rated at
8 Ohms output impedance please check
with the amplifier manufacturer that the
output stage can handle 4 Ohm speakers
without problems.
An amplifier and speakers inter-act in a
complex manner, and they must be
matched accurate-ly if you are aiming at a
really top-class sound experience. If you
want the best, the simple question
' how
many Watts does the amplifier supply? ' is
not enough. We suggest that you check he
following points when you are selecting an
amplifier.
Output power
There are two aspects to an amplifier's
output power: continuous sine-wave power
and peak power. When considering output
stages you should be sure that the power
figures you are comparing refer to the
same type of power.
You should also check that the
manufacturer of the amplifiers states the
output power with both channels running
simultaneously, since it is only this figure
which corresponds to the actual use of the
equipment under normal circumstances.
 loudspeakers are very efficient and
therefore do not require an extremely high
continuous power output. A value of
around 50 W per channel into 4 Ohms is
quite enough for normal listening volumes
in a small room when you are using small
speakers. For bigger speakers and rooms
with a floor area greater than 30 sq m we
recommend an amplifier capable of 100 W
per channel. Extra power has a positive
effect on the overall dynamics of the
system, and greater reserves are available
for rendering fine detail in the reproduced
music and resolving highly detailed and
complex music signals.
However, the stability of the output stage
is much more important than the sheer
quantity of watts of output power.
Stability is crucial in deciding how well the
amplifier copes with phase fluctuations
which occur with all types of loudspeaker.
An amplifier's current supply capability is a
crucial factor in determining its stability.
A good criterion for asses-sing cur-rent
capacity is the amplifier's out-put power
into 2 Ohms, which should not be less
than the value into 4 Ohms.
An amplifier's mains power supply is also
a fair indication of the stability you can
expect from the unit. Here the size (weight
of the mains transformer) and the value of
the supply reservoir capacity are decisive.
Basically it is also true that a mains power
supply
whose reservoir capacity is
distributed amongst many smaller
capacitors responds more quickly than a
conventional mains section, and is
therefore able to supply higher currents
even at high frequencies.