Audio Analogue Verdi Cento Owner's Manual - page 5
AUDIO FUTURA
AUDIO FUTURA
AUDIO FUTURA
AUDIO FUTURA
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Verdi Cento Integrated Amplifier
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Power Amps Power Supply
We
have
dedicated
a
secondary stage for each
power stage channel to
decrease the crosstalk and
increase the “sound stage”
definition.
The
power
amps power supplies take
advantage of the high
power toroidal transformer
and discrete high current
rectifier bridge have been
used to allow high current
peaks. There are four
10000uF capacitors after
the
bridge
for
each
channel (so 40000uF for
each channel!) and a lot of
capacity
has
been
distributed close to the
Power amps to provide the
charge
for
fast
audio
responses. The big capacitors and the discrete bridge we have used allow the power stages to
perform very highly in bass reproduction. The particular solutions adopted in the power
supplies allow the realisation of the high signal to noise ratio expected from the power stage
circuit used.
2.
Vacuum Tube Preamplifier Stage
The vacuum tube preamp section is the first active stage the audio signal meets in the unit and
it is placed after the input selection circuit and the volume control. The Preamp not only has to
amplify the signal and adapt the impedances but must also provide two out of phase signals to
drive the bridge configured power stage. The unit is based on a “classic” and well-known
scheme that we have developed to decrease the output impedance and match the application.
Moreover, the fact that it produces zero feedback is its main outstanding characteristic. This
means we haven’t modified the vacuum tube distortion characteristics in any way and we have
let the vacuum tube play “as it is” (remember the “philosophy”…). Nevertheless, the overall
distortion is kept low with a higher power stage gain that lets the preamp section work with a
low level signal at all times.