
gain
selector knob
input
selector knob
headphone
socket
record
selector knob
volume
knob
remote control
window
mute
LED
power
LED
power
button
3
GAIN
6
9
12
15dB
RECORDINPUTVOLUME
0dB
aux
tuner
cd
tape 1
tape 2
tape 3
cd
tuner
aux
tape 1
tape 2
tape 3
left
right
left
right
out 3 2 1in out in out
right
in
left
right
left
right
ground
transformer
balanced
(option)
transformer
balanced
(option)
3
left
31 aux tuner cd
left
right
SOURCE
serial
number
220-240V
~
50-60Hz
Fuse: T1A L250V
made in United Kingdom
TAPE
OUTPUT
2
output
sockets
tape in/out
sockets
ground
terminal
input
sockets
XLR output
(optional)
XLR output
(optional)
ac supply
socket
fuse
carrier
PA2 1234567
02 welcome
08 key features
10 getting started
12 selecting an input
14 volume control
15 gain control
17 headphones
18 grounding
19 outputs
21 connecting power amplifiers
27 running in and warming up
28 care and maintenance
30 technical data
34 international standards
contents
Specification shown may vary for different countries
GRA00046.1-[CA]PA20R 13/03/01 11:11 Page 1

03
Now,this blend of talent and
expertise has been combined
with the award-winning
experience of Audiolab to create
a company with a technical
advantage and access to
resources second-to-none in the
high end audio industry TAG McLaren Audio.
TAG McLaren Audio has been created with
one aim in mind:to produce the best highfidelity audio and audio-visual systems
available.Now the first fruits of that
alliance are ready – a unique new range of
audio products.
Throughout the F3 Series development
process,quality,performance and
reliability have been paramount,resulting
in unparalleled performance,operational
excellence and sheer listening pleasure.
celebrating a TAG McLaren victory
All TAG companiesperpetually strive
for,and achieve,excellence and highperformance in every area of their
business.
These qualities are demonstrated in the
fastidious standards that make TAG Heuer
watches some of the world’s most
admired;in the teamwork that makes TAG
McLaren’s motor racing team one of the
most successful in Formula One;and in the
advanced electronics technology that
makes TAG Electronic Systems the first
choice for many Formula One constructors
and high-performance car makers.
Derek Scotland (on the left) – Technical Director
Peter Stevens – Chief Industrial Designer
Dr. Zucker – Chief Executive
welcome to a new partnership
..in hi-performance, hi-fidelity
GRA00046.1-[CA]PA20R 13/03/01 11:11 Page 3

We are convinced it will give you many hours of
listening pleasure.
The PA20R is a high-performance preamplifier which acts
as the command centre for your audio system.It has
microprocessor-controlled relays with gold-plated contacts
for its switching functions and,for added convenience,you
can select inputs,adjust the volume or mute the output by
remote control.‘Straight Line Technology’gives the PA20R
exceptional sound quality with an unusually
wide and flat frequency response.
Furthermore, by painstaking attention to
detail,TAG McLaren Audio engineers have
ensured that the versatile control facilities
do not affect the excellent sound quality.
In particular,the ‘Time Constant Switching’
system ensures that the muting period is
short even though the frequency response
reaches as low as 0.1 Hz.
versatile input
and recording selection
The PA20R has six selectable inputs and
three outputs for recording.A separate signal
path is provided for recording,with its own
independent input selector,so you can
record one piece of music while listening
to another.The microprocessor-controlled
relay switching system in the PA20R
welcome
welcome
0504
Thank you for purchasing the TAG McLaren Audio preamplifier PA20R.
includes a lock-out function to prevent
feedback loops when using a tape recorder.
low intermodulation distortion
The theoretically-ideal preamplifier
reproduces sound perfectly over an infinite
range of frequencies – starting from well
below the audible range and extending far
above the capabilities of human hearing.
Although sound outside the human hearing
range of approximately 20 to 20,000 Hz
cannot be heard,it can significantly distort
the quality of music reproduction through
an effect that audio engineers call
‘intermodulation distortion’.This type of
distortion moves imperfections that
originate outside the hearing range back into
the audible frequencies.To minimise this
effect,TAG McLaren Audio preamplifiers
have a frequency response which extends
GRA00046.1-[CA]PA20R 13/03/01 11:11 Page 5

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 lowfrequency 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
0706
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.
GRA00046.1-[CA]PA20R 13/03/01 11:11 Page 7

‘Straight Line Technology’ with direct coupled signal and
feedback paths
High-quality audio components
Independent input selection for listening and tape recording
Six line level inputs for: cd, tuner, auxiliary, and three tape
recorders
Digitally-controlled muting system, with ‘Time Constant Switching’,
operates automatically and by remote control
Motorised volume control and input selector can be operated
manually or by remote control
Remote control also operates selected TAG McLaren Audio F3
Series CD players
Gain selectable in six steps
Three stereo outputs for recording
Two low-impedance stereo outputs to allow long cable runs
An additional transformer-coupled and balanced output, via the
fitted XLR connectors, can be supplied as an option
Headphone output for a wide range of impedances with
automatic muting when headphones are plugged in
Sorbothane
®
sonic isolation feet specially, designed by
TAG McLaren Audio
(1)
•
•
•
•
•
•
•
•
•
•
•
•
•
08
09
key features key features
1. For the very best per formance we recommend that our units are placed on
individual shelves and are not stacked one on top of another
GRA00046.1-[CA]PA20R 13/03/01 11:11 Page 9

We know you are keen to get your PA20R working. This section
will have you listening to your favourite music as quickly as possible.
If you fold out the front cover of this manual, you will locate
diagrams which will help you find your way around your PA20R
(1)
.
Make sure that all the components of your audio system are
disconnected from the AC supply whenever you change any
connections.
You will need a source of audio signals (such as our CD player
CD20R or our tuner T20) to feed into your PA20R. Use a goodquality, screened phono-phono audio cable to connect the phono
output sockets of your sound source to the appropriate pair of
left and right sockets marked SOURCE aux,tuner, cd or TAPE in
1, in 2 orin 3 on the back of your PA20R
(2)
.
Use a good-quality, screened phono-phono audio cable to connect
the phono sockets marked OUTPUT 1 left and right on the back of
your PA20R to the corresponding inputs of your power amplifier.
Check that the power button is out so that power is off when you
plug in
(3)
. Using the cable supplied, connect the socket on the back
of your PA20R to an AC supply outlet. For the best sound quality,
we recommend that you do not use multi-plug adaptors.
before
you start
sound source
connection
amplifier
connection
power
connection
Turn the VOLUME right down (all the way anticlockwise).
Set the INPUT selector to the input to which you connected your
sound source.
Set the GAIN to 9 dB.
Press the power button in. The blue power LED will come on.
Wait for a few seconds until the mute LED on the front panel
goes out
(4)
.
Start playing your sound source.
Turn up the VOLUME, sit back and enjoy the music.
setting controls
switch on
10
11
getting started getting started
1. Throughout this instruction manual (except in titles), bold print indicates the
lettering that you will find on the panels of your PA20R
2. The inputs for cd, tuner, aux, TAPE 1, TAPE 2 and TAPE 3 are all the same
electrically. They are named for your convenience
3. The power button is a latching switch. One press will hold it in, the next will
release it
4. The output is muted when the power is switched on to allow all the voltages to
stabilize. This protects your amplifier and loudspeakers and prevents unpleasant
switching noises from upsetting your listening experience
INPUT
cd
tuner
aux
tape 1
tape 2
tape 3
VOLUME
GRA00046.1-[CA]PA20R 13/03/01 11:12 Page 11