control of volume and gain
Volume control on the PA20R is via a
motorised potentiometer.This gives you the
convenience of remote control without the
disadvantage of stepped volume changing, as
you might find in a digital electronic system.
The PA20R also has gain control to allow
you to select the right amount of
preamplification for your system to keep the
volume control near the middle of its range.
The gain switching facility is also used to
provide the correct volume range for a
wide variety of headphones.
high-quality circuitry
The circuits in the PA20R are ‘no-
compromise’ designs using high-quality,
high-stability components to send a smooth,
clean signal to your power amplifier for
excellent sound quality. As a further
both above and below the range of normal
human hearing.
straight line technology
To prevent intermodulation distortion,
a preamplifier must respond to very low
frequencies but block any Direct Current
(DC).This is traditionally achieved using
capacitors, which also block some of the low-
frequency signal. In the PA20R, a feedback
circuit eliminates DC offset voltage and
allows the signal path to be direct coupled
without any capacitors.This arrangement,
which we at TAG McLaren Audio call
‘Straight Line Technology’, is easy to describe
but not easy to realise.The design has taken
our expert engineers years to perfect.
time constant switching
The PA20R has a sophisticated muting
system which protects your hi-fi and
prevents annoying, loud switching noises
from reaching the output. A preamplifier
that responds to low frequencies will ‘ring’
for a long time in response to the sudden
voltage changes that happen, for example,
when you select a different input. A muting
system that simply waited for the switching
transients to die down naturally would take
far too long to settle.To overcome this
problem, the PA20R incorporates a
technique developed by TAG McLaren Audio
called ‘Time Constant Switching’.
This changes the characteristics of the
preamplifier during input switching to
reduce the settling time, so that the mute
period can be as short as possible.
welcome
welcome
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refinement, the power supplies for the
right and left stereo channels have separate
regulators to prevent any interaction
between channels.
versatile analogue output
Two low-impedance outputs are provided
for connection to power amplifiers. As an
option, the PA20R can be fitted with an
additional transformer-coupled, balanced
XLR output for improved resistance to
electromagnetic interference and mains
frequency hum.
The PA20R, at the heart of your system,
keeps everything at the highest level of
hi-performance, hi-fidelity.
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