Perreaux Radiance R200i, Руководство пользователя

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71
Preamplifier
Specifications
Explained
Preamplifier attenuation....................................................................... –95dB
Preamplifier gain..................................................................................+30dB
Gain resolution............................................................................. 2.0dB steps
(linear throughout the range)
Frequency response..................................................5Hz – 100KHz ±0.25dB
Comments
This is the “standard” specification with which everyone is familiar.
Actually “frequency response” is a misnomer. Technically, the
specification should be called “amplitude response versus frequency” for it
describes how uniform the amplitude or strength of signals of various
frequencies is maintained. It is generally thought that a difference of 1dB
is the least that can be perceived by the ear. The preamplifier section has
been designed to exceed this value by a very comfortable margin.
Input sensitivity...................................................................................205mV
Comments
There are many ways of specifying “sensitivity”. The numbers indicate the
input level required to achieve “rated” output (1.45V
rms
) with the volume
control fully advanced. Since the output is sufficient to drive most power
amps to their maximum output level, the sensitivity figures indicate the
minimum input levels you will need to drive the power amplifier to its full
capability. Dividing rated output voltage by input sensitivity rating gives
the “gain” of the preamplifier.
Input impedance....................................................................................10K Ω
Comments
Input impedance defines the “load” that the preamplifier presents to the
source that is driving it.
Input overload ......................................................................................3.80V
Comments
“Input Overload” specifies the maximum signal level that each input circuit
can handle without clipping.
Rated output..................................................... 1.45V
rms
into 10K Ω or better
Comments
This is the reference output level to which other specifications, such as
sensitivity, are referred. Rated output does not indicate the preamplifier’s
full capability. This is given by the maximum output, as follows.