Cambridge Audio 340A Stereo Amplifier User Manual


 
2 azur integrated amplifier
Thank
you
for
purchasing
this
Cambridge
Audio
azur
series
amplifier.
It
is
the
result
of
our
most
extensive
ever
research
and
development
program
in
over
three
decades
of
produci
ng
high
quality
audio
products.
We
hope
that
you
will
appreciate
the
results
and
enjoy
many
years
of
listening
pleasure.
About
this
amplifier
The design of a high quality but cost-effective audio amplifier presents
a major challenge. Providing first-class performance on an unlimited
budget is one matter; achieving the same performance within tight price
limits is quite another, and requires the expertise and experience that
Cambridge Audio brings to its product design process. We believe we
have succeeded in our aim of creating a first-class affordable amplifier.
The wide bandwidth of this amplifier is ideal for the new "better than CD"
high bandwidth sources such as DVD-audio and Super Audio CD.
The power amplifier stages follow the same basic architecture that
Cambridge Audio have used in previous award-winning amplifiers, with
refinements to match it to its exact application in the Azur 340A. The
power amplifier input circuitry uses dual differential pairs, linearly
buffered from the input to establish optimal operating conditions. A
carefully controlled amount of local negative feedback is used in this
stage to define the stability margins so that any reactive load may be
driven effortlessly.
The output stage uses large-area silicon devices, with exceptionally
rapid thermal compensation to maintain correct output stage conditions
and so prevent crossover distortion, even under widely varying drive
conditions.
The power amplifiers incorporate an electronic muting system that
reacts extremely quickly and allows the complete suppression of
switching clicks, such as may occur when changing inputs or turning the
amplifier on and off.
The power supply is a vital part of a power amplifier. The Azur 340A
power amplifiers are fed from a power supply of elegant simplicity that
avoids the complications and uncertainties of regulated supplies. A
toroidal transformer selected for low external magnetic field, is used in
conjunction with generously specified reservoir capacitors and optimally
placed decoupling components.
Close attention has been paid to the performance and quality of the
passive components used, both in the signal paths and for decoupling
purposes.
The Cambridge Audio Azur 340A incorporates tone controls that give
vernier control of the frequency response, allowing the correction of
dubious source material, and compensation for loudspeaker
inadequacies or problems with room acoustics. These tone controls can
be switched completely out of the audio path by use of the DIRECT
switch, to give the shortest possible audio path. Other features include
24-carat gold-plated phono sockets, a tape send/return loop, a
headphone socket, and a second set of switchable loudspeaker
outputs.
The Cambridge Audio Azur 340A has full protection against misuse and
possible faults. The overload and short-circuit protection systems
continuously monitor the voltage, current and temperature of the output
devices, allowing the protection to act positively in case of genuine need,
but never triggering spuriously.
INTRODUCTION