HP Barney Oliver, Руководство пользователя

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The Barney Oliver Audio Amplifier
EC ION I
E CRI TION
A. GENERAL
The Oliver Amplifier is a high
quality all solid state audio amplifier designed for
two channel stereo sound
in the
in and in small to medium sized
auditoriums. It is intended for use with full fre­
quency range 8 to 16 ohm and
with signal sources (phonograph pickups,
AM and FM tunners) that are themselves
flat enough to little or no In
addition to the power the unit includes
phono designed to operate from any
of several phono cartridges. These pre-
the necessary equalization for
characteristic. Additional
boards, install and wire printed
connectors in the deck, front or rear
required, and
switch
Hum and distortion are inaudible. As a
result of attention to and to lead
routing on circuit the residual
hum is well below thermal noise (which itself has
been minimized by
input
The output of the amplifiers are operated
class-B to reduce standby power drain and are
biased and
degenerated to reduce crossover
distortion.
A
amount of overall feed-
from over
100
dB gain at de and
low frequencies to over
50
dB at the of the
audio range further reduces any har-
monic and inter-modulation distortion. Since the
are direct coupled, overload
no long time constant the are
simply clipped and the original waveform resumes
at its proper value immediately afterward. Be-
cause of the
amount of feedback,
only a fraction of a dB below actual overload
typically show a total distortion over
75
dB below
the fundamental.
networks in the fi-circuits of the
amplifiers, and active filters in the and
control board, enable the low-end response to be
maintained down to
20
Hz and to fall off very
rapidly below the audible range. This prevents the
and
from being driven
their linear excursions by low frequency
transients from such sources as
records or breath blasts into
The
end response is reduced at 18 dB per octave above
20
kc another pair of active filters to protect
the amplifiers overload or
of, strong r-f signals.
The power are protected
from accidental short-circuits at their out­
puts. Momentary shorts will have no
sustained shorts may blow one or more of the pro­
tective fuses. In addition, all power
are either current limited or fused so that shorts
from test
will in cause no
considerable effort was devoted to
transients. A balanced
and decay of power
of function
transients in the
low voltage
and careful
minimizes the tum-on
A slow tum-on in the
further reduces the
turn-on transient from the
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