icon Audio Stereo 300 MK II Guide

Page 1
icon Audio
Instruction Manual and User Guide:
Stereo 300 MK II
Pictured with upgraded David Shaw CV181/6SN7
Contents
1 Introduction & Final Inspection
2 Quick Set Up Guide
3 Connecting inputs & outputs
4 Getting the best out of your amplifier
5 Trouble Shooting
6 Bias Checking & Valve Replacement
7 Specifications
8 Packing and Shipping
1 Introduction
Thank you for purchasing the Stereo 300. This
unique design by David Shaw is the result of a
lifetime working with audio amplification. A great
deal of care has been taken in the design,
selection of components and production of this
amplifier. With a little care and attention, the
ST300 should give a lifetime of pleasure.
The Stereo 300 is a Pure Triode integrated valve
amplifier running in fixed bias push-pull mode.
Fixed bias allows all of the power to be used to
drive the speakers in Class A/B mode where the
important first 5 Watts are class A.
The pre-amplifier is a high quality ‘Passive’ circuit
using silver audio cable and an ALPS volume
control with remote control. The ST300 is
sensitive enough to be used with virtually any
modern source. A pre-amplifier may be used if
desired using the “low sensitivity” mode.
The circuit design is our own using only three
stages employing the venerable 6SN7 (CV181)
giving an excellent combination of the best of
vintage valve sound, yet accurate and dynamic to
suit modern speakers and recordings.
In order to get the best out of your amplifier,
please read the enclosed notes. Even if you are
experienced with valve amps please read the
‘quick set up guide’. Should you be uncertain
about using your amplifier please contact us for
advice.
Valve (or Tube) amplifiers do the same job as a
solid state amplifier, but they do it differently. And
whilst solid state specifications look good on
paper even quite modest valve amplifiers can
have a richer, more textured sound. Our “old
school” method of point to point wiring hand wiring
without using printed circuit boards significantly
adds to the sound quality. Your ears may have
become accustomed to your old amplifier, so it
may take some hours before your ears attune
themselves to the new sound.
Your source, loudspeakers and room acoustics
will also affect the sound before it finally reaches
your ear. Some people find a small adjustment in
re positioning their speakers can help too. The
weakest link will always affect the listening quality.
When making judgements use a good well
balanced recording. Remember that a new
amplifier will take a few months to fully “burn in”.
IMPORTANT!
THIS MANUAL CONTAINS
ESSENTIAL HEALTH & SAFETY
INFORMATION FOR YOU AND
YOUR AMPLIFIER. PLEASE
READ & KEEP SAFE AND
REFER TO IF NECESSARY

Page 2
Final Inspection - Your Guarantee of Quality
To assure you of optimum performance and reliability, this amplifier has passed our rigorous
final inspection and listening test by the Icon Audio team in Leicester. During which the final set
up and adjustments were made.
Date …./…./….
Model ……….
Amp Serial Number ……….
Customer ……………………………
Check amplifier finish ……….
Check valve cover ……….
Internal wiring check ……….
Run 48 hour test ……….
Check inputs & tape monitor ……….
Output Valve Bias level ……mv
Sound Quality ……….
Channel Balance ……….
Valve Microphony ……….
Valve Seating ……….
Hum level left/right ...../…..mv
RF Test ……….
LED brightness ……….
Mains voltage 117V / 230-240V
IEC Mains Fuse T3.15A (T5A USA)
Internal HT fuse x2………………………….
UK Plug Mains Fuse …….5A
Remote Control Functions ……….
Sales invoice ……….
Bottom label ……….
IEC power cable type .………
Customer survey form .………
Packed for shipping/collection
Capacitor type ……………….
Output valves ……....……….
1st Stage valves ……………….
2nd Stage valves ……………….
Other
……………………………………………….
……………………………………………….
……………………………………………….
……………………………………………….
……………………………………………….
Signed off by
……………………….
Notes:
BOX CONTENTS:
ST 300 MK II amplifier
Valve cover
Remote control
IEC power cable
Manual
4x 300B
4x 6SN7/CV181
Screwdriver for bias adjusting
1x spare mains fuse (in IEC socket drawer)
2x spare HT fuse (inside amplifier)

Page 3
IMPORTANT YOU MUST READ THIS FIRST!
2 QUICK SET UP GUIDE
1 Unpack unit carefully and check that it is in
good condition. Transit damage must be reported
to your supplier immediately. It is important that
you keep packaging for warranty/service return.
2 If Necessary fit the valves, or check that they
are in the correct position, firmly in place. The
valves are numbered on the base. The large 300B
valves need fitting in the rear 4 pin sockets V1-V4.
Before fitting note the 300B larger pair of pins!
These should be aligned with the black dots on
the valve socket.
Note Left and Right pairs are in “Mirror Image”.
The smaller 6SN7/CV181 valves should be fitted
V5-V8 sockets. YOU MUST OBSERVE THE
CENTRAL “SPIGOT” WHEN INSERTING THE
VALVES. Inserting the valves incorrectly will
damage both valves and amplifier and will not be
covered by the warranty.
Do not push or pull the valves excessively by
the glass envelope, this could cause the glass
envelope to become detached from the base,
damaging the valve. Take care to observe the
alignment of the centre spigot when inserting all
valves.
3 Connect to source units, using any line level
source (appox 300mV to 3V) e.g. CD, Tuner,
Tape, Phono pre amp (if used) etc via appropriate
phono sockets. This also includes TV, Streamer,
Bluetooth etc observing L (left) and R (right).
The “Tape” switch should be set to “Source”.
Switch “Sensitivity” to “H” initially.
4 Connect to speakers Usually “Black” to “0”
terminal and “Red” to either 4 or 8 Ohm terminals.
Modern speaker impedance can fall as low as 2
Ohms and rise as to more than 30 Ohms, so the
“nominal” figure quoted by manufacturers has little
practical meaning, therefore you may wish to try
both, the type of speaker and room acoustics can
also have a big effect, so choose by personal
preference.
If ‘bi-wiring’ both ‘common’ should go to the black
terminal, and both ‘positive’ (or red) should go to
either 4 or 8 ohm terminals. (A second banana
plug may be fitted vertically in the hole of the
socket stem).
5 Ensure that the side power switch is “OFF”
at “0” Then connect to mains supply using
supplied IEC mains lead to your wall supply. If for
some reason the welded plug must be
removed, please remove fuse and dispose of
immediately. (As they can be dangerous if
plugged in). The replacement plug should be
wired in the following way Brown to Live terminal,
Blue to Neutral terminal and Green/Yellow to
Earth.
6 When first switching on the “standby”
switch should be in the “down” position.
Then switch “On” the meter should light up. The
meter will light up and the amplifier should start
working within about 30 seconds. 300Bs glow
very dimly. With the volume control set to
minimum (fully anti-clockwise) there should be no
sound coming from the speakers except a barely
discernible hum. If there are any unpleasant
sounds coming from the speakers, switch off and
refer to the ‘Trouble Shooting’ section or contact
your re-seller or Icon Audio.
Check the BIAS of the 300Bs by switching the
Bias switch from 1-4, the pointer should be in or
close to the black section and all four should be
the same. “Standby” is a power saving mode
which will keep the valves hot ready for use.
7 Your amplifier should now be working.
Select a suitable “source” and adjust volume.
If not check wiring again and/Use selector/tape
monitor/volume to choose source program and
suitable listening volume. Do not operate at a high
volume for the first five minutes to allow the valves
to warm up properly.
8, Remote Control. You may need to remove
plastic tape (if any) to activate, if necessary
loosen the rear screws. If the batteries are good
(2x AAA) the LED should light when any of the
keys are pressed. A little skill is needed in pointing
and pressing, as the unit has a motorised “pot”. At
switch on the volume control re-sets to “9 o’clock”.
Please note all these things are normal for
valve amplifiers:
A, Valves can get very hot, BEWARE!
B, The transformer cover will get quite warm
C, The amplifier may smell slightly for a few weeks.
D, Mobile phone ‘breakthrough’ is normal. Moving
your phone further away normally stops this.
E, Valves may make a ‘tinkling’ sound when
warming up and cooling down.
F, Nearby appliances such as boilers/fridge/wifi
etc occasionally may be a source of interference.
8 Health and Safety. The valves when operating
have high surface temperatures. Keep out of
reach of children and pets. The use of the
supplied guard is recommended in these
circumstances. Always unplug when making
adjustments. Like all amplifiers there are
potentially lethal high voltages inside (over
500v DC), which when switched off can take
twenty minutes to discharge! Do not remove
bottom panel unless you are a competent
engineer. There are no user serviceable parts
inside. Like other household electrical
appliances do not leave unattended whilst
switched on. Do not adjust the output valve grid
bias pre-sets without reference to the manual.
Incorrect adjustment could cause the valves to
overheat, with damage to valves and amplifier.
To maintain the best performance of the
amplifier you should check the bias of the
output valves occasionally (say monthly). Full
details will be found in section 7.

Page 4
3 Connecting inputs & outputs
Most problems associated with electronic
equipment involve connecting leads, which are
usually either ‘BAD CONNECTION’ or a
‘WRONG CONNECTION’. So it’s worth making
sure that you have good connections and that
your leads are the right way round.
Inputs
The amplifier will work with any standard piece of
hi fi e.g. CD, Tuner, Tape Deck, Mini Disc, TV,
Video Recorder, DVD etc having an output of
approx. 300mV or more, to get full power.
Balanced outputs need a suitable adaptor.
If you wish to use a turntable you will need a
phono pre-amp. Icon Audio make several pure
valve models ideal for the ST300. See our website
or your dealer can advise you.
“H, L, 0” sensitivity/Power Amplifier mode.
The sensitivity switch of the amplifier does not
attenuate the signal by resistors but by varying the
amount of negative feedback within the amplifier.
“H” (High) gives the sensitivity of an “integrated”
amplifier with a small amount of feedback.
“L” (Low) has a lower sensitivity giving a less
steep volume control and higher Damping Factor.
And is better suited if you are using a separate
line pre-amplifier.
“0” (Middle) This position uses no feedback
therefore has very high sensitivity and a lower
damping factor. Designed to be used mainly for
servicing but if preferred may be used normally.
We suggest “H” (upper) position initially.
Connecting a tape deck/Recorder/Equaliser
The STEREO 300 will work with any tape deck
having suitable output, and it is possible to record
from any connected source using the terminals
marked ‘REC OUT’. Playback via The STEREO
300 has a ‘Tape Monitor’ facility, which enables
you to use a ‘three head deck’ or an equalizer.
Some tape decks ‘Present a load’ to the amplifier
terminals, even when not in use, which can affect
sound quality. (You can do an audible check for
this by removing the plugs and listening for a
change). Therefore for best results do not leave
anything connected to “Rec out” unnecessarily.
Connecting loudspeakers
It is important to use good quality loudspeaker
cable. This should be relatively thick and multi-
stranded. e.g. QED ‘Original’ or better. Take care
to connect the correct polarity. The use of
‘Banana plugs’ or ‘spade’ connections will ensure
a good connection whilst minimising the risk of
‘shorts’. You also can either ‘hard wire’ your cable
to the amplifier by baring enough cable to fit in the
connector and twist together to avoid any spare
strands touching anywhere else (soldering the
stands together helps). The amplifier does not
have an output protection device, which can
degrade the sound. So a prolonged short due to
strands of wire touching could damage the valves.
In our experience valve amplifiers are more
tolerant of cables, therefore the benefits of ‘exotic’
cables may be wasted! But this is personal taste.
Icon or your dealer will advise you.
Speaker cables have minimal loss, keeping each
speaker cables shorter than 10m will help.
Speaker polarity. It is essential that you
observe the polarity of the terminals; they
must be the same for the left/right connections
at the amplifier end and at the loudspeaker
end. Otherwise the sound will be ‘out of phase’
with the sound stage ‘inside out’ with reduced
bass. If you are unable to check this or confirm
the polarity (e.g. if you have ‘built in’ wiring), try
the following; Connect the system up and play
some music with plenty of bass (e.g. dance
music), preferably in mono and stand the
speakers close together. If correct you should
hear plenty of bass, reversing the terminals for
one channel only should result in less bass. The
higher bass output is the correct setting to use.
Another alternative is to use a test disc.
The STEREO 300 is designed to work with full
range, medium to high efficiency speakers having
impedance of about 4-8 Ohms. Speakers having
efficiency of lower than 86db will have greater
difficulty in providing a high sound level. But this
will also depend upon individual speakers, room
size, type of music and positioning etc.
Loudspeaker impedance.
If using 15-ohm speakers use the 8-ohm
connections. If you are unsure or “6 ohms” or “4 to
8 ohms” is quoted; a rule of thumb guide is to try
both positions. The 4 Ohm position will have a
little more “bass weight”. Although your personal
taste should be the final deciding factor.
Do not connect to more than one pair of speakers
for each channel. If two pairs of speakers are
required to be connected, they must both be 8-
ohm and connected to the 4 ohm terminals.
Contact Icon Audio for more information. Sound
quality may be impaired if the amplifier is not
correctly loaded.

Page 5
4 How to get the best out of your amplifier
Do not leave the amplifier switched on all the time. This is not necessary. Use “Standby” for short
periods if not required (max 2 hours) (not recommended for W.E. 300Bs).
Do not switch off and on without a short rest of at least 60 seconds
Do not adjust the output valve grid bias unless you know how, see section 6 below
Do not operate the amplifier without loudspeakers connected
Do not use valves other than listed as there could be danger of shock or damage to the amplifier
Do check the bias regularly about once a month for best performance.
Make sure the loudspeakers are in phase.
Use the best possible source material.
Using larger, more efficient well-designed speakers will give a huge benefit in overall sound.
What is safe maximum volume?
The Stereo 300 is designed to work continuously
at any sound level that is not distorted. Some
recordings have a large dynamic range so if
operating at a high volume beware loud transients
which could become distorted.
The meter is set to read 100% when both
channels reach maximum sine wave power (one
channel only will read 70%). As music is generally
consists of fast “transients” which the meter will
not show, meter indications of around 70% will
approximate the maximum undistorted power.
Should this not be enough for your loudspeakers,
this may indicate that a more powerful amplifier is
required.
Leaving the amplifier switched on
The Stereo 300 will start working within 60
seconds and will be fully warmed up in about ten
minutes. Should the amplifier not be needed for a
limited time it may be left in the “standby mode”,
this will save power. (Not W.E. 300Bs)
Do not leave the amplifier switched on 24/7. Your
valves will be worn out in approximately nine
months! Never leave the amplifier switched on
when unattended. Always switch off when not
in use.
Standby Switch.
This facility is not strictly necessary for 300Bs and
the heat up time is almost instant.
Western Electric have informed us that they do
not recommend using “Standby”.
It is possible that some other brands of 300B we
are not aware of may recommend not using
“Standby”, we suggest you contact your valve
supplier.
“Standby” allows you to save power if the amplifier
is not needed for a short time (say up to 2 hours)
reducing the power consumption to 50w, with the
valves remaining hot and ready for use.
‘
Burning in’
A new amplifier can take up to approximately 6
months of regular use to be reach its optimum
sound. This is a slow process and will continue for
several months as it involves all the various
components settling within the amplifier as well as
the valves.
Upgrading Valves!
Good quality new valves will generally sound
better and more lively than worn valves . It is
important to have the valves “matched” in pairs or
quads. This includes the 6SN7/CV181s having
both halves matched.
The valves supplied with this amplifier have been
tested, matched and aged for the best
performance. New valves need testing, grading
and matching. Ideally they will have been tested
and aged in a ST300 to ensure best performance.
You are welcome to contact us for this service.
Cabinet Care
To remove dust use a small paint brush.
Other marks can usually be removed with a damp
cloth and dry with a duster.
Never use anything wet on the amplifier, and
always clean with the power disconnected.

Page 6
5 Trouble Shooting
1. Amplifier Dead
Check the power fuse at the back of the amplifier. To
gain access, remove the mains lead. The fuse is in a
small plastic drawer, which forms part of the socket
assembly. To open insert a flat bade screwdriver or
similar and prise open. The fuse in use is the
innermost the outer is a spare. Should the replacement
fuse also blow there is a fault, contact you dealer or Icon
Audio. Replace with the same type Available from Icon
Audio free in the UK (outside the UK you must pay
postage).
The fuse in the power cord plug (if any) should be a 5
amp fuse, although unlikely, this should be checked if
the amplifier fuse is OK. Or try another cable.
2. No sound or one channel missing
Have you selected the right input?
Are all the connections OK?
Are the speakers connected at both ends?
Is everything switched on?
Is the “standby” switch down?
If you have tried everything and the meter light is
working and the heaters are glowing either the left or
right internal fuses may have blown. There is a single
fuse for the left pair of 300Bs and one for the right pair of
300Bs looking from the front.
In that case there would be “0” bias reading for that
channel. (It is extremely unlikely that both internal fuses
would have blown).
Check the bias reading for the valves on that channel. If
there is no reading, the likely cause is the internal fuse.
There are two spare HT ceramic fuses taped to the
bottom plate. Ideally these should be replaced by a
qualified person, but if this is not possible follow these
instructions.
1. Disconnect mains lead for 10 minutes.
2. Number and remove 300Bs and 6SN7s.
3. Invert amplifier and remove bottom plate.
4. Replace fuse for suspect channel (test old fuse if
possible).
5. Re-assemble amplifier by reversing the procedure.
6. Switch on and check the bias for that channel.
Should the fuse blow again or the fault remains switch
off and refer to your dealer or Icon Audio.
The correct fuses are available from Icon Audio free of
charge (postage payable outside the UK).
Distorted sound.
One channel or both? Try another source; if sound
improves then it’s probably something wrong with the
first source. If there is no improvement and you know it is
not the loudspeakers, if so it could be an amplifier
problem but it is unlikely to affect both channels.
You can usually find the problem is by swapping
connections over. And swapping Left input with Right.
Hum Adjustment
Will only need doing if replacing the 300Bs. The
filaments are heated by AC. This causes hum to be
introduced into the circuit which can be eliminated by the
hum adjustment adjacent to each pair of 300Bs.
Method. If a meter which reads AC at 1-10mV is
available connect to the loudspeaker terminals with the
loudspeaker still connected and adjust for minimum
hum. Normally this would be 1-2mV.
Alternatively, this could be done with one person
making the adjustment and another listening closely
to the bass speaker for minimum hum. The volume
should be set at “zero”. Only a small adjustment
should be necessary.
Other Causes of hum/noise.
1. Establish if the hum is internal or external to the
amplifier. If the hum disappears with no inputs
connected the problem is with the source and/or
interconnects.
2. If the amplifier has serious hum/noise, this may be
a fault. Contact your dealer or Icon Audio.
3. Hum Loop. If the hum is only on one input, you
may have a “hum loop” caused by too many “ground”
or “earth” connections. A possible remedy for this is
to use an interconnect which only has the screen
connected at one end. Other causes of low-level hum
can be from adjacent equipment, so experiment with
moving equipment around to see if this makes the
hum better or worse.
4. Intermittent noise on one channel such as rustling,
crackling, hiss etc may be due to a 6SN7/CV181
valve. The valve may be identified by swapping
valves from left to right. This is occasionally a poor
pin contact, rocking the valve gently may prove this,
in which case clean the pins, otherwise the valve
should be replaced.
Interference Problems
This amplifier design is resistant to mains-born
interference. But some heating systems, fridges,
cookers etc. can generate RF (radio frequency)
interference which travels through the air (and walls).
Although rare this can be very irritating. Relocating
the equipment will often help. Or a simple suppressor
capacitor will often cure this. Mobile phone
interference is normal for up to 1-2 meters away.
Valve Life and Replacement
Valve life will depend upon such things as hours of
use and number of on/off cycles, Do not switch on
and off unnecessarily (see Standby). The 300B
valves are operating in “CLASS A/B” mode (approx.
5 Watts output) which means they are using relatively
low current all of the time. Therefore we would
suggest for use of more than 3 hours per day replace
the valves every 5 years. This excludes filament and
other failures which happen randomly. The small
valves sometimes “go noisy”. Valves may be
returned to Icon Audio for free testing. They should
be well packed.
Service: Should you suspect a problem, you could
return the unit to Icon Audio or one of our agents for
a periodic service or repair. If you are outside the UK
contact Icon Audio.
Mains Supply
This amplifier is hard wired to work on 230/240v AC
(or 117v US). The transformer may be re-configured
by an engineer for 117v ac. Contact for information.

Page 7
6. 300B Bias Check & Adjustment
If you are unsure about any aspect of bias contact
your retailer, Icon Audio or a competent service
engineer.
The Stereo 300 uses the ‘Fixed bias’ method of valve
operation. This method gives higher power, lower
feedback and cooler running. However you should
regularly check the bias reading using the built in meter
to ensure best performance from the amplifier. This will
tell you that the 300B output valves are operating
normally. Adjustment is not usually needed. This is very
easy using the built in meter for V1 to V4 left to right.
1, Tools you will need:
A small flat blade screwdriver.
2, How to check the valves and read the meter.
If the amplifier is working normally at zero volume with
the amplifier warmed up with Standby “off”, volume at
“zero” move the “bias” selector through V1-V4. These
are the output valves left to right (viewed from the front).
Each valve should have the black pointer in or near the
black section. (50-75). Precise adjustment is not
necessary. This will not affect sound quality.
Only adjust if necessary, (see below) and repeat for
V2/3/4.
A high reading (80+) needs adjustment, as this valve is
drawing too much current. Lower than 50 will cause no
harm but the performance will be reduced.
NOTE
3. The readings are affected by changes in your local
mains voltage. So if all four valves are slightly high or
low this is normal. Check again another time.
4. How to adjust the bias:
Make sure you are reading the valve to adjust, e.g. read
V1 to adjust V1 screw. If the reading is incorrect, set this
by using the screw very slowly up or down until the
correct reading is obtained. They are very sensitive so
adjust very carefully. If the reading appears a little
unstable this is normally due to mains fluctuations.
You may need to repeat this a couple of times as the
adjustment of one valve may affect the other readings.
Allow 20 minutes to fully warm up.
5, If one or more valves are showing erratic readings or
you cannot set the correct voltage, then that valve is
probably faulty or out of specification. If you are unable
to set the reading high enough this usually means the
emission of the valve is too low.
Replacing the 300B Valves
Important: Do not attempt to change the 300Bs
without reading these notes. Failure to do so could
be both dangerous and damaging to the amplifier.
When replacing valves, we recommend that you use
“matched pairs” , for best performance.
Use only 300B valves. Western Electric do not
recommend the use of “standby” for long periods.
Health & safety; High voltages are present inside the
amplifier and on exposed valve sockets when valves
are removed, so take suitable care. It is not
necessary to remove the bottom cover. Beware
valves get hot in operation!
5, Changing valves: You should if possible check the
bias setting before you attempt to change the valve(s), in
order to familiarise yourself with the procedure.
Replace and bias one valve at a time. Remove the
first old valve and fit the replacement. Switch on and
measure and adjust the bias.
Do not allow the reading to go above 95. Don’t worry
how low the reading goes this will not cause damage.
Repeat in the same way and fit V2, V3, V4. Do final
adjustment when the amplifier is fully warmed up.
If all is well there should be no more than a barely
detectable hum from the speakers, and the amplifier
should sound OK when tested. You may need to
adjust minimise the hum. See section 5 “Hum
Adjustment”.
6, If you cannot set up the bias then that valve is
probably faulty.
If the valves are brand new, you will need to check
again after approximately 10 & 100 hours, after that
only occasionally or if you suspect a problem.
7, To avoid damage to the amplifier and electric
shock hazard you must use only valves marked
300B, and 6SN7/6N8/CV181 Or that you know to
be direct equivalents. Use only valves which you
know to be new or good condition and test the
amplifier thoroughly before resuming normal use.
8, Replacing the small valves:
These are four 6SN7/CV181 valves. None of these
requires any set up procedure. It’s just ‘plug and
play’, although care should be taken when removing
and inserting not to break the centre spigot.
Icon Audio are happy to check your valves Free of
Charge if you send them to us in Leicester. We will
also gladly check you ST300 and re-bias free of
charge for personal callers. (By appointment please)
The 3 fuses inside this amplifier are critical safety
parts They should only be replaced with the same
type. These are available without charge (in the UK)
from Icon Audio. Outside the UK postage is
chargable.

Page 8
7 Specification & Features
(Typical conditions @ 235v 50Hz)
300B output valves
4x 6SN7 (CV181) double triodes
Low, medium and Zero feedback options
Icon designed and manufactured Tertiary wound
output transformers
Hand wired point to point components
No printed circuit board
Ceramic valve bases for low noise/leakage
32W maximum output 8 Ohms
25W maximum output 8 Ohms (Lower HT mode)
Signal to noise level -88dB
Freq. response 20Hz -0.2dB to 20kHz -0.5db 8w
0.3% THD at 8 watts
Channel balance typically less than 0.1 dB
4 and 8 ohms output taps
Choke regulated power supply
Supplied valve cover
Audiophile quality metal film resistors
SCR Audiophile polypropylene audio caps
Optional Mundorf capacitor upgrade
Japanese ALPS volume pot.
Rubicon/Nichichron power caps.
Internal wiring using PTFE silver plated cable
Valves carefully matched for best performance
Gold plated Input & speaker terminals
Line level Inputs for CD, Tuner, Aux, etc
Record loop with monitor switch
140, 300, 790mv sensitivity options
230-240volts 50 Hz for EU and UK countries
117v 60Hz for USA Canada
50 W Standby 150w 0 signal. 235 Watts max
IEC SKT T3.15A (T5A 117V) fuse (with spare)
Internal HT fuse 315ma T ceramic. (2x spares)
380W, 220H, 380D mm Amp overall 25kg
Carton= 55x53x38cm 30kg packed
IEC mains lead
Conforms to CE ROHS and WEEE where applicable
Specification subject to change without notice.
*RMS watts Do not literally exist! But this figure is based upon the RMS
voltage output (V²/R) to indicate continuous output as opposed to “peak”
output which is mis-leading.
*Triode a simple valve with only 3 elements, this gives very linear
amplification. Some “pentode” (5 element) valves can also be wired to act as
“pseudo” triode valves (not in this amplifier).

Page 9
Guarantee
(UK only) This amplifier is guaranteed by your
dealer or reseller for 12 months from the date of
purchase for parts and labour, excluding
shipping. Valves are consumables and therefore
on a 12 months pro-rata wear basis.
Other countries may vary, ask your re-seller.
Please keep your receipt as proof of purchase,
this may be needed.
In the event of any difficulty you are welcome to
contact us.
Exclusions
Claims for any damage to either amplifiers or valves
must be reported within three days of receipt.
This amplifier is designed for normal domestic hi fi
use. It is not guaranteed for commercial, Public
Address use, or use in other situations. The
guarantee becomes void if the unit has been
modified in any way not approved by Icon Audio.
Future service and spares
Your dealer should be able to provide any support
you need. Or you are welcome to contact for advice,
spares and repairs.
We expect our amplifiers to give a service life of
approximately 20 years, with regular maintenance.
During this time we will make every effort to supply
spare parts and repair them at an economical cost.
Supply is subject to availability from third party
suppliers which Icon Audio is not responsible for.
This does not cover unique parts including remote
control systems, meters and cosmetic parts.
If you believe the unit is not functioning correctly, it
may be helpful to contact us first as we may be able
to assist you. Then we would request that you return
the item to us for further action.
You are advised to inform us of any change of
address in order that we may keep you up to date of
any upgrades or improvements. Check our website.
Returning for service
Should your amplifier need service in the UK return it
to the address below with a description of the
problem.
Outside the UK contact your dealer/distributor. In
case of difficulty email us at the address below.
8 Packing Instructions
It is essential that the original box and packing be
kept in good condition, as this provides vital
protection during transit. Please do not write on
box, but use removable labels. If returning for
service do not send the cover, as this is easily
damaged. The valve cover is normally supplied in a
separate box with the valves. We recommend that
the cover be sent separately as rough handling
can damage both cover and amplifier.
Re-use the supplied plastic bag to keep the
amp clean and free from damp.
The mains lead and remote control fits in a
foam cut-out underneath the amplifier.
Valves should be removed, numbered and
packed in “Bubblewrap” or similar for
protection inside the valve cover.
If the amplifier is stored in the box, keep
upright and remove batteries from remote
control to prevent corrosion.
icon Audio (UK) Ltd
351 Aylestone Road Leicester LE2 8TA
Email: [email protected]m www.iconaudio.com
Phone [phone] [phone]
Gen 28/03/2022

Page 10
Caution: This amplifier is very heavy!
Lift the amplifier out of its packing by
using the two “hand cut-outs” in the
bottom packing near the transformers.
Or you may find it easier to remove the
unit using the following procedure:
1. With the top packing in place, turn
the box “upside down” with the “flaps”
open.
2. Lift the cardboard box off.
3. Remove the bottom packing first.
4. Turn the unit the right way up and
remove the top packing.
Please be careful not to damage the
small switches on the front panel
When re-packing please make sure the packaging does
not foul the small switches. Normally the two hand cut-
outs are towards the rear of the amplifier.
Do not ship with the valve cover as damage is likely to
occur, but send separately. Do not return valve cover
for service.
(Please keep this information for future use).