Perreaux SM6 MKII User manual

Prisma
SM6 MkII
Balanced Preamplifier
Owners Manual

2
Perreaux Industries Limited makes no warranty for the use of its products, other than those
expressly contained in the warranty detailed herein. The Company assumes no responsibility for
any errors which may appear in this document, reserves the ri ht to chan e products or
specifications detailed herein at any time without notice, and does not make any commitment to
update the information contained herein. No licenses to patents or other intellectual property of
Perreaux are ranted by the Company in connection with the sale of Perreaux products, expressly or
by implication.
mboob^ru
®
is a re istered trademark of Perreaux Industries Ltd.
Terms and product names in this document may be trademarks of others.

3
i
ii
i Introducing the Perreaux
SM6 MkII Preamplifier
Con ratulations on your Perreaux SM 6 MkII
purchase. To realise the full
potential of your unit you need to appreciate all aspects of its operation.
Before installin the SM6 M kII
into your system, read the entire manual
carefully. Endeavour
to understand every detail by familiarisin yourself with
the controls and features as you read. You will find it easier to install usin the
relevant sections of this manual as a reference.
We have attempted to explain every feature and operation
facet clearly and
concisely. Your Perreaux dealer will be happy to assist if you encounter any
unforeseen problems.
Read this manual, install your unit correctly and realise the sonic si nificance of
your investment in Perreaux.
Perreaux products are desi
ned to provide the utmost in sonic realism and
electronic reliability with a functional yet ele ant appearance that reflects the
care and craftsmanship applied durin all sta es of construction.
Features at a
Glance
 Ru ed build quality
 Truly balanced circuit desi n
 Discrete Class-A amplification throu hout
 Multiple re ulated power supplies
 Infrared (IR) full function remote control
 Precision volume control
 Dual preamplifier outputs
 Home theatre bypass
 Remote tri er outputs
 Advanced PCB desi n and earthin techniques
To maintain the consistently hi h quality that you expect from us, and we expect
from ourselves, Perreaux products are essentially handcrafted.
We maintain the human-
link throu hout, from desi n and construction, throu h
to the ultimate test, your music, your system, your ears.
Because we too listen to our products, we know that with your Perreaux you will
discover many more of the musical secrets we strive to reveal.
From all of us at Perreaux Industries Limited, thank you for choosin th
e
Perreaux Prisma Series SM 6 MkII preamplifier.

4
ii
iiii
ii Important Safety Instructions
Note:
All safety and operation instructions should be read carefully before the
SM6 is operated. Keep the Owners Manual in a safe place for future
reference.
 The SM 6 should not be used near water, for example near a bathtub,
kitchen sink, in a wet basement, near a swimmin pool, etc.
 Mountin to a wall or ceilin should be via a heavy-duty bracket or shelf
desi ned for audio equipment use.
 The SM 6 should be situated away from heat sources such as radiators,
stoves, or other appliances that produce excessive amounts of heat.
 DO NOT place the SM 6 directly onto carpeted surfaces.
 Avoid exposin the SM 6 to extremely hi h or low temperatures.
 The SM 6 should be connected to a mains power supply only of the type
described in the operatin instructions, or as marked on the rear of the
unit.
 DO NOT disconnect the mains earth from the system.
 The mains power supply cord should be routed so that it is not likely to
be walked on or pinched by items placed on or a ainst it.
 The power cord of the SM 6 should be unplu ed from the mains outlet
when the unit is to be left unused for lon periods or when attemptin to
connect or disconnect cables and before cleanin your unit.
 Care should be taken so that objects and/or liquids do not accidentally
fall inside the SM6.
 Please keep electrical equipment out of reach of children.
 Please unplu sensitive electronic equipment durin electrical storms.
 Please replace any fuse with the value and type specified.
 Avoid operatin the SM 6 with the cover removed.
 DO NOT bypass any fuse.
 DO NOT attempt to repair the SM6. In the event of a problem, please
contact your Perreaux dealer.
 DO NOT operate this product in an explosive atmosphere.

5
iii
iiiiii
iii Table of Contents
i
ii
i Introducing the Perreaux SM6 Preamplifier...............................................................3
ii
iiii
ii Important Safety Instructions ........................................................................................4
iii
iiiiii
iii Ta le of Contents ..............................................................................................................5
1
11
1 Unpacking and Placement..............................................................................................6
2
22
2 Instant Install......................................................................................................................7
3
33
3 Front Panel Functions......................................................................................................9
4
44
4 Rear Panel Functions..................................................................................................... 11
5
55
5 Remote Control Functions........................................................................................... 15
6
66
6 Special Design Philosophies ........................................................................................ 18
7
77
7 Special Design Features................................................................................................ 20
8
88
8 Maximising System Potential ...................................................................................... 21
9
99
9 Care and Maintainance................................................................................................ 23
10
1010
10 Warranty Information and O taining Service........................................................ 24
11
1111
11 Extended Warranty Registration Form.................................................................... 25
12
1212
12 Faultfinding Your System............................................................................................. 26
13
1313
13 Specifications................................................................................................................... 31
14
1414
14 Physical Dimensions ...................................................................................................... 35
15
1515
15 Contact Details................................................................................................................ 36

6
1
11
1 Unpacking and Placement
The SM 6 is packa ed for maximum protection. Please carefully read the
instructions below before proceedin to unpack the unit. Be extremely careful.
Unpacking
Procedure
 Inspect both ends of the cardboard box and open at the end without the
central staple by slittin the reinforced tape at either side.
 Fold back the flaps and tip the packa e on end and the inner box will
slide out.
 Lay the inner box down flat and upri ht, open it conventionally by
separatin the top tray from the bottom.
 The product can now be removed from the bottom packa in . This will
be easier if you have someone to help you by holdin the base of the
box.
 Alternately, the bottom tray and preamplifier could be tipped upside
down and the bottom packa in removed. If opened in this manner,
please ensure that you turn the contents over a ain.
Note:
Be very careful to secure the unit if you are planning to flip the pac age
upside down.
 Remove the two rey foam protectors off either side of the unit, leavin
the black material coverin .
 Pull back the material and remove the protective membrane from the
front panel.
The preamplifier is now unpacked and ready for further installation.
Note:
Please retain all pac aging material for future transport.
Box
Contents
1 x SM 6 MkII Preamplifier 1 x Screwdriver
1 x SM 6 MkII Product manual 2 x Remote tri er leads
1 x Perreaux remote control 1 x Detachable AC power cord
2 x AAA batteries 3 x Performance analysis charts
Placing
Your SM6
The SM6 should enerally be placed close to your amplifier, keepin the
interconnect cablin short. Position all the separate components of your system
close enou h to your SM 6 to avoid havin to stretch or extend any of the
interconnect cables.
As a “rule of thumb”, allow 80-100mm (3-
4 inches) around all sides of the
product and mount the SM 6 on a flat surface, ensurin that the unit has adequate
access to free flowin air.
Do not place auxiliary equipment directly on top of the SM 6.
Do not place the SM6 directly atop a power amplifier.
Please do not cover the product with a cloth or similar.

7
Instant Install
If you are like us, the first thin you will want to do is to play your favourite
piece of music throu h your new SM 6. The followin inst
ructions are written to
enable you to achieve this as quickly as possible. These are not comprehensive
instructions, but are desi ned to enable you to play music now!
Note:
Please ta e the time to read the SM6 manual thoroughly as it
incorporates many features, which will enhance its operation.
Placement
The SM6 is a reference preamplifier and best results will be achieved when
placed on a solid surface with adequate ventilation. DO NOT place on
a
carpeted floor or cover the preamplifier!
Turn off associated components
This minimises the potential to dama e any other components when connectin
your SM 6 into the system.
Connect SM6 to power amplifier
Connect the balanced (XLR) or unbalanced (RCA) outputs of your SM6 to the
appropriate inputs at the rear of your power amplifier.
Note:
Try to eep all interconnect cables as far from loudspea er cables as
possible and well away from all AC mains leads.
Connect source component to SM6
Connect the relevant output of your source component to either the b
alanced
(XLR) or unbalanced (RCA) inputs of your SM 6.
Note:
Be sure to set the Balanced I
nput switch to the appropriate position, ON
if using the balanced (XLR) inputs and OFF if using the unbalanced (RCA)
inputs.
Switch on source component
Turn on the
source component and make sure you have some pro ram material
ready to play.
Switch on SM6
After checkin the supply volta e compatibility with the volta e ratin on the
SM 6 rear panel, insert the power cord-
set supplied into the rear of the unit and
int
o the wall. Switch on the socket at the wall and power up the SM 6 usin the
switch on the rear panel.
Switch on power amplifier
Turn on your power amplifier.

8
Test for undesira le noises
Without any pro ram source material, slowly increase the SM6 vol
ume listenin
for any undesirable noises. After establishin that there are no problems, return
the SM6 volume level back to zero.
Play your source material
Start your source material playin .
Increase the volume
Slowly increase the volume on the SM 6 to achieve a comfortable listenin level.
CONGRATULATIONS!
Now that you have achieved your first objective, sit back, relax and please read
the rest of the manual at your own pace, in your favourite armchair, whilst
sippin a lass of wine. You’ll find the wh
ole experience much more
pleasurable whilst listenin to music.

9
3
33
3 Front Panel Functions
Volume Control and Stand y
Volume Control
When either button is depressed, they
will alter the volume settin . The volume
adjustment ran e is 00 – 59 (-95dB to +18dB), with 47 indicatin 0dB.
Standby
Pressin simultaneously will put the SM 6 into standby,
disconnectin all power
supplies except the di ital power supply for the microcontroller and turnin off
the remote tri er outputs. The selected input and balance settin s are saved.
Standby is indicated by a sin le dot on the display and operation can be resumed
by pressin buttons simultaneously a ain.
Refer to Chapter 5 “Remote Control Functions”, for further details on volume
and standby controls.
Alphanumeric Display
The display will illuminate when the power is turned on at the mains power
switch or when various remote or front panel adjustments are made. At turn-
on,
the display will illuminate with 00 and default to the input
selected at the last
standby cycle.
Source Select and Mute
Source Select
When either button is depressed, they scroll throu h the source inputs.
The order of source inputs and display indication is as follows:
Source Input Display
Input A IA
Input B IB
Input C IC
Input D (HT Loop) HT
Input E IE
Input F IF

10
Caution!
Input D (HT Loop) fixes the output to 0dB,
as it is a home theatre bypass.
Please ensure the level is suitably attenuated by the upstream processor
or receiver before selecting this input.
Note:
The source selecto
r has six positions and supplies the chosen source to
the Pre/Balanced outputs and Tape outputs. If source
input E or F is
selected, no signal is supplied to its applicable Tape
output to avoid the
potentially damaging feed bac loop which can occur if in
advertently
attempting to record and playbac the same source simultaneously.
Mute
Pressin the buttons simultaneously will mute the volume
, indicated by “MU”
on the display. M ute can be cancelled by pressin the buttons simultaneously
a ain, or increasin
the volume settin . The volume settin can be decreased
whilst the volume remains muted.
Note:
The mute function still operates when
source input D (home theatre
bypass) is selected.
Refer to Chapter 5 “Remote Control Functions”, for further details
on source
select and mute controls.

11
4
44
4 Rear Panel Functions
Caution!
Observe precautions regarding volume control settings. Please ma e all
changes at minimum volume setting. Only increase the volume after the
connections have been made.
Balanced Inputs
Accepts a si nal from a source component
with balanced outputs via hi h
quality XLR connectors.
The use of ood quality balanced line cable into the
balanced input cause the input si nal to be relatively immune to noise and
external effects cause
d by the use of lon interconnect cables, helps reduce hum
loop noise and aids in the cancellation of distortion products.
The pin assi nments of the balanced XLR input connectors are as follows:
Pin 1: Signal ground
Pin 2: Signal + (non-inverting)
Pin 3: Signal – (inverting)
Shield ground: Chassis ground
Note:
Please refer to the operating manuals of your balanced output line level
source to verify that the pin assignments of the output connectors
correspond to the SM6 balanced inputs. In the event tha
t they are not
compatible, the interconnecting cable will need to be altered to suit.
Balanced Input Switch
This switch selects which input to use for source input A
. Set to ON if usin the
balanced (XLR) inputs and OFF if usin the unbalanced (RCA) inputs.
Note:
Do not connect source equipment to both the balanced and unbalanced
inputs at any one time.

12
Note:
The position of the Balanced Input switch has no bearing on the
balanced output, it only selects which input to use for input A
. Set the
Balanced Input switch to ON only when using the balanced input.
..
.
Refer to Chapter 13 “Specifications”, for detail on input sensitivity and
impedance.
Un alanced Source Inputs
Accepts a standard sin le-
ended input (RCA) from source components with
sin le-e
nded analo ue outputs. These hi h quality old plated sockets are
hi hly conductive, corrosion resistant, and provide less potential for corrosion
induced distortion.
Caution!
Input D
fixes the output to 0dB, as it is a home theatre bypass. Please
ensur
e the level is suitably attenuated by the upstream processor or
receiver before selecting this input.
Refer to Chapter 13 “Specifications”, for detail on input sensitivity and
impedance.
Tape 1 Line Outputs
This sin le-ended (RCA) output will provide a
line level audio si nal, suitable
for recordin , from the selected source input. This output is disconnected when
source input E is selected; to prevent any potentially dama in feedback loops.
Tape 2 Line Outputs
This sin le-ended (RCA) output will pr
ovide a line level audio si nal, suitable
for recordin , from the selected source input. This output is disconnected when
source input F is selected; to prevent any potentially dama in feedback loops.
Preamp Output 1
This sin le-ended (RCA) output is
commonly referred to as “Preamp Out”. It
will provide the audio si nal required to drive virtually any amplifier to full
power.
Preamp Output 2
This sin le-
ended (RCA) output is wired in parallel with Main Output 1 and is
useful for supplyin si nal to another amplifier if bi-ampin .
Balanced Outputs
This balanced (XLR) preamplifier output provides the si nal required to drive
virtually any power amplifier equipped with a balanced input. Connection
should be made with hi h quality cables fitted with XLR connectors.
Note:
The position of the Balanced I
nput switch has no bearing on the
balanced output; it only selects which input to use for source input A.

13
The pin assi nments of the balanced XLR output connectors are as follows:
Pin 1: Signal ground
Pin 2: Signal + (non-inverting)
Pin 3: Signal – (inverting)
Shield ground: Chassis ground
Caution!
Please refer to the operating manual of your amplifier to verify that the
pin assignments of the input connectors correspond to the SM6 balanced
out
puts. In the event that they are not compatible, the interconnecting
cable will need to be altered to suit.
Input Voltage and Fuse Rating
Input Voltage
It is important that the SM6 be operated from the correct AC mains volta e.
This unit is factory
set for the volta e applicable to the ori inal country of
destination.
The SM6 will operate satisfactorily within a volta e variation of up to ±5% of
that volta e at which the unit has been set.
If you require the volta e settin to be altered, e. . reloca
tion to another area,
city or country, or extraordinarily hi h or low volta es, please contact your
Perreaux dealer. Qualified service personnel can only perform this modification.
Caution!
Never attempt to connect the unit to the incorrect voltage. Sev
ere
damage can result from applying incorrect voltage to the unit.
Fuse Rating
The fuse ratin displayed here, refers to the ratin of the mains inlet fuse.
For more information on fuse ratin s, please refer to Chapter 13
“Specifications”.
Caution!
Neve
r replace the fuse with any other ratings other than the one
specified.
Serial Num er
The serial number is unique to your SM6. Please record this number and store it
in a safe place. For any service related enquiry, please be prepared to quote the
product serial number to Perreaux personnel or their service representative.
Remote Trigger Outputs
Two parallel remote tri er outputs are provided to switch on or off any
connected peripherals to the SM 6. In the event that it is not possible to cascad
e
connect peripherals, two outputs are provided. The remote tri er outputs are
desi ned to accept a mono, 3.5mm diameter, male jack. The volta e ratin is
+5V DC when ON and 0V DC when OFF with maximum current bein 10mA.

14
The plu must follow the specifications as per the dia ram below:
AC Mains Input
An IEC-
standard mains input is provided at the rear of the unit. The AC cord set
is removable, allowin you to up rade to a cord set of your preference.
Caution!
Prior to connection to the AC mains
, please chec the voltage label on
the rear panel to ensure that your unit conforms to the power supply in
your area. Never attempt to connect the unit to the incorrect voltage.
Severe damage can result from applying incorrect voltage to the unit.
AC Mains Fuse
The SM6 is equipped with a user serviceable AC mains fuse. In the event of
fuse failure, always replace with the same type and value fuse. Remember, fuses
do not usually blow without a reason. Any doubts about fuse failure should be
conveyed directly to your Perreaux dealer.
For more information on fuse ratin s, please refer to Chapter 13
“Specifications”.
Caution!
This is the ONLY user accessible fuse.
Never replace the fuses with any other ratings other than the one
specified on the rear panel.
Always ensure your SM6 is disconnected from the mains supply before
attempting to change the mains fuse.
Power Switch
Depress this switch to the ri ht (I
) to turn power ON. M ute relay circuitry is
employed in the SM 6 and output is muted for 1 t
o 2 second after the power
switch is actuated. Depress this switch to the left (O
) to turn the SM 6 off at
which time the outputs will be disconnected.
Note:
The SM6 resets the volume to minimum at turn-on.

15
5
55
5 Remote Control Functions
The SM6 comes supplied with a 36
button Perreaux Universal infrared remote
control.
The remote control uses 2 x AAA batteries and may be chan ed by
removin the
black perspex insert.
Note:
Press the button on the remote to select the code-
set required to
control the SM6.
The SM 6 uses the followin functions:
Stand y
Pressin this button
puts the SM6 into standby, disconnectin all power supplies
except the di ital power supply for the microcontroller and turnin off
the
remote tri er outputs. Standby is indicat
ed by a sin le dot on the display and
operation can be resumed by pressin standby a ain or selectin a source input.
Mute
Depressin this control causes volume to be muted
. The display will indicate
"MU" and the volume will remain muted until the volume level is increased
, or
the mute button is depressed a ain at which sta e volume will be returned to the
previous settin .
Note:
The mute control has a ‘punch through’ function and will operate
regardless of the code-set selected i.e. you can be operat
ing the CD
player remote functions and still use the mute control without
selecting
the button first.
Display
Pressin this button will cause the display to turn off,
and is intended for use if
the li ht of the display is distractin (for instance in a darkened room).
Any
operations performed will be momentarily displayed before resumin a
turned
off state. The display can be turned on by a ain pressin the display button.
Balance Left / Balance Right
The balance controls al
low you to vary the level of either the Left or Ri ht
channel to obtain the correct stereo balance for your listenin position. Pushin
the Balance Left button will cause the level of the ri ht channel to be attenuated
(decreased in volume). Pushin the
Balance Ri ht button will cause the level of
the left channel to be attenuated.
Durin any balance adjustment the display will indicate the direction of
adjustment, left or ri ht, with an "L" or an "R" followed by a number indicatin
the level of adjustment. The ran e is L1-L9 and R1-
R9. "LR" on the display
indicates the balance is centred.

16
Note:
Balance settings are stored when the unit is put into standby.
/ Input A Source Select
Depressin selects source input A and the relevant code-set
to control the
compact disc player. Pressin selects source input A only. Source input A
is
indicated by “IA” on the display of the SM 6.
/ Input B Source Select
Depressin selects source input B and the relevant code-set
to control the
tuner. Pressin selects source input B only. Source input B
is indicated by
“IB” on the display of the SM6.
Input C Source Select
Depressin this control selects source input C. Source input C
is indicated by
“IC” on the display of the SM6.
Input D Source Select (home theatre ypass)
Depressin this control selects source input D. This offers a preamplifier bypass
for home theatre applications. Home theatre bypass mode is indicated by “HT
”
on the display of the SM 6.
Note:
Volume and balance functions are disabled in
home theatre bypass
mode, although the volume can still be muted.
Input E Source Select
Depressin this control selects source input E. Source input E
is indicated by
“IE” on the display of the SM 6.
Input F Source Select
Depressin this control selects source input F. Source input F
is indicated by
“IF” on the display of the SM6.
Volume Up
Depressin this button increases the volume.
Volume Down
Depressin this button decreases the volume.
Note:
The Volume control has a ‘punch through’ function and will operate
regardless of the code-
set selected i.e. You can be operating the CD
player remote functions and still use the volume controls without
selecting the button first.

17
Scroll Source Up
Pressin this button scrolls the source input up, selectin in the order:
IA  IB  IC  HT  IE  IF 
Scroll Source Down
Pressin this button scrolls the source input down, selectin in the order:
IA  IF  IE  HT  IC  IB 

18
6
66
6 Special Design Philosophies
Perreaux has been desi nin and manufacturin only the hi hest quality audio
componentry for more than a quarter of a century. Technolo y has continued to
evolve rapidly over that time and our knowled e and application of d
esi n,
materials and manufacturin techniques has advanced in tandem with this.
Today’s Perreaux ran e comes closer to fulfillin our shared vision than at any
other time in the past.
To follow is a discussion on some of Perreaux desi n philosophies that
have
been incorporated into the entire ran e.
Minimalist
Design
Leadin British architect, John Pawson, writes:
“The Minimum can be defined as the perfection that an object
achieves when it is no longer possible to improve it by subtraction.
This is the quality that an object has when every component, every
detail, and every junction has been reduced or condensed to the
essentials. It is the result of the omission of the inessentials”.
Perreaux has historically embraced the minimalist ethic from an audio
desi n
perspective only. The concept of
“less equatin to more” has been at the heart
of all Perreaux audio desi ns for more than a quarter of a century.
Minimalist Electronics
We wish to maximise the quality of your listenin pleasure by keepin the
com
ponentry and si nal path as uncluttered, short and clean possible. All
components in the si nal path, even those of the hi hest quality have an effect
on the si nal, thereby alterin the quality of the reproduction in some way. Our
aim is to recreate in
its entirety, the ori inal performance by not addin or
subtractin anythin , irrespective of the source.
Minimalist User Interface
We carefully study the user interface and par down the number of buttons and
associated clutter leavin just the essential a
nd no more. How temptin it has
been over the years to loose si ht of our core values as technolo y or trends
have made it possible. That is one of the reasons why our older products still
have such a hi h resale value today. The user interface has and
always will
remain simple, free from adornments, clean and uncluttered.
Minimalist Aesthetics
Our products appeal to those who seek the ultimate in audio exclusivity, namely
the perfect blend of “form and function”.

19
“Form and function” are both tou
h masters. That is why our amplifier heat
sinks are not hidden, but instead feature prominently in all our desi ns. We
make no excuses for producin some of the most distinctive hi h-
end audio
products on the planet. We let “form and function” blend to
ether in perfect
harmony. This surely is the essence of true minimalist utilisation.
Minimalism in a Wider Context
John Pawson writes:
“Clearly simplicity has dimensions to it that go beyond the purely
aesthetic it can be seen as the reflection of some innate, inner
quality, or the pursuit of philosophical or literary insight into the
nature of harmony, reason, and truth”.

20
7
77
7 Special Design Features
Rugged Build
Quality
Mechanical stren th has been a hallmark of Perreaux products since the
company firs
t started production back in 1974. The concept behind the physical
desi n and construction is that each structural member should contribute to both
ri idity and performance.
Balanced
Design
The SM6 is a truly balanced preamplifier, from input to output.
The positive
and ne ative halves of the si nal never touch, remainin balanced throu hout all
sta es. This circuit topolo y offers the ultimate in performance, providin
increased noise rejection and lower levels of distortion.
Class A
Output
Four discr
ete output sta es operatin in Class A provide output bufferin . This
enables low impedance loads to be driven, over lon cable len ths usin any
cable.
Multiple
Power
Supplies
There is a separate power supply for each section of the preamplifier. One f
or
each of the volume control chips (two chips are used to keep the system fully
balanced and therefore, to maintain separation, each chip is supplied with it’s
own separate power supply), another one for each of the output bufferin sta es
(once a ain bec
ause the SM6 utilises a fully balanced circuit topolo y), another
for the di ital lo ic and the final power supply looks after the input relays. The
advanta e of this is that there is complete isolation from sta e to sta e. The
di ital noise is kept comp
letely out. This is further evidence of a thorou hly
desi ned product offerin .
Infrared (IR)
Remote
Control
Many audiophile rade components are still provided with analo ue controls
that are adjusted on the faceplate of the unit. The SM 6 features an i
nfrared (IR)
remote control meanin
you don’t have to et out of your chair to make an
adjustment. Some of the functions available are: standby,
mute, volume
up/down, display on/off, input select and balance.
Earthing Perreaux en ineers pay particular at
tention to desi nin the product to ensure
maximum separation between internal si nal and power earths, only meetin at a
central starred point.
Precision
Volume
Control
The SM6 uses two di itally controlled resistor ladder volume controls. This is
becau
se we treat the positive and ne ative parts of the si nal separately (true
balanced topolo y). The advanta es of usin a di itally controlled analo ue
resistor ladder to adjust volume are precise control, no contacts to corrode
creatin wiper noise and no analo ue component drift.
Dual Outputs
You do not need to purchase an RCA style splitter if you want to drive two
separate power amps simultaneously, as there are dual parallel preamplifier
outputs.