Amplifier Recommendations - T+A KS 350 Handbuch

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 6 or 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 accurately 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 the 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.
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