Astin Trew AT5000 User manual

ASTINtrew
6 Varnell Terrace
Hambleden Oxfordshire RG9 6SA
Telephone: +44 [0]1491 414494
Facsimile: +44 [0]1491 413303
Email: [e-mail]
Website: www.astintrew.co.uk
AT 5000

Operating information for the ASTINtrew AT5000
dual mono power amplifier.
1. Introduction
2. Unpacking
3. AC mains supply
4. Safe use
5. Set up
6. Operation
7. Valve and fuse replacement
8. Troubleshooting
9. Specifications
10. Guarantee
11. CE, RoHS and WEEE
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PAGE
SECTION

1. Introduction
Congratulations on your purchase of
the ASTINtrew dual mono power
amplifier. This amplifier has been
designed and manufactured to a very
high specification making it a true
audiophile product. It will give you
many years of listening pleasure. The
following notes explain all aspects of
the user functions and will help you
get the very best from it.
The ASTINtrew AT5000 power amplifi-
er uses both valve and solid-state
amplification devices within the design
to offer an involving musical experi-
ence. As with all audiophile products,
the other components you use within
the chain will also affect the quality of
sound you experience. This power
amplifier deserves high quality ancillary
components to give its best and works
particularly well with other ASTINtrew
range products.
2. Unpacking
Included with your ASTINtrew stereo
power amplifier you will find:
One mains lead with plug fitted.
One Alan key.
One operation manual.
One spare fuse, located in fuse holder,
see section 7.
Please retain all packing materials.
Correct re-packing may be necessary
if you wish to transport your amplifier
in the future without risk of damage to
the equipment.
3. AC mains supply
This amplifier is designed to work on a
220-240VAC supply only.
4. Safe use
This amplifier generates some heat
when switched on. Do not place on a
carpet or any material where the
amplifiers feet may sink into the sur-
face and obstruct the ventilation slots
on the underside of the unit.
Do not place anything on the top of
the amplifier which may obstruct the
ventilation slots.
Do not allow liquids or objects to fall
into the ventilation slots. If liquid does
enter the ventilation slots, do not
touch the amplifier, but immediately
disconnect from the mains at the wall
socket, then inform your dealer, who
should check the unit before further
use. Entry of liquids into the amplifier
is dangerous and may cause electric
shock or fire hazard.
The amplifier should be located in a
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well ventilated area and kept away
from sources of heat, dust, humidity
and direct sunlight.
Do not attempt to change or alter any
component or part of this amplifier
except for those which are user
replaceable (see sections 6 and 7).
Unauthorised adaptations will
void the warranty and may
damage the amplifier.
Clean the outside surfaces with a dry
lint free cloth. Some cleaning and pol-
ishing agents may cause marking to
the surface finishes.
All electronics is susceptible to local
lightening strikes affecting the mains
cabling in your home. When not in
use, the safest option is to remove
the mains plug from the wall socket.
5. Set up
The mains lead supplied with has an
IEC mains plug on one end which plugs
into the amplifiers rear panel. The
other end is fitted with an appropriate
mains plug of your country. In the UK
this is the standard UK13A plug.
The high-quality performance of this
amplifier will be impaired if the electri-
cal supply to it is in poor condition.
We recommend that you use a high
quality wall socket directly, or a multi-
way socket unit designed for audio
use. If you live in an area with very
‘dirty’ or variable mains supply, you
may also wish to try a power supply
conditioner to optimize fidelity.
The RCA phono input connections
should be connected to an appropriate
pre-amplifier or other audio equipment
with an output volume control. We
recommend the use of high-quality sig-
nal cables for optimum performance.
Placing the equipment on an audio
equipment rack, table or support,
offering maximum isolation from
mechanical vibration is recommended.
The loudspeaker connectors will
accept either bare wire, 4mm banana
plugs or spade terminals. Use high
quality loudspeaker cables for optimum
performance. There are two pairs of
outputs for both channels, allowing
you the option of bi-wiring your loud-
speakers if they are designed for this
option and you wish to experiment.
See Illustration, page 5.
Ensure that the loudspeaker cables
are fitted in phase. Do not short out
the cables when in use as this may
damage the amplifier.
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AT 5000 front view

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AT 5000 rear view

6. Operation
The power amplifier on-off switch is
located on the left side of the front
fascia. The blue LED light above the
switch is illuminated when on. See
illustration, page 4.
We recommend that the amplifier is
turned on half an hour or more before
you wish to use it. This is not essen-
tial but we think our amplifiers sound
better once they have ‘warmed up’.
We do not recommend that you leave
it on all the time but it will come to no
harm if you do. From new, you will
find that the amplifier will need up to
100 initial hours use to achieve its
optimum audiophile sound.
The valves fitted have been selected to
offer a high quality performance. If
you wish to experiment with alternative
manufacturers’ valves, after the
warantee period, replace with ECC 82
(12AU7) types. Other valve types may
damage the amplifier.
In the unlikely event of the amplifier
failing to work properly when first
switched on please refer to trou-
bleshooting in section 8.
7. Valve and internal fuse
replacement.
Replacing or substituting the valves; or
replacing the internal fuses in the
unlikely event of failure, can be carried
out by your dealer or distributor. If
you attempt to replace either compo-
nent, the following instructions must
be adhered to.
Note: Dangerously high voltages
are present inside the unit, when
powered from the mains supply,
that can kill.
NEVER open the amplifier when
attached to the mains supply.
A. Disconnect the amplifier from all
equipment and the mains supply.
Place on a table or work bench with
plenty of space around the amplifier.
Caution: Wait 1 hour before opening
cover to allow the valves to cool and
capacitors to discharge.
B. Undo the 10 x Alan screws in top
plate with key provided, Put the
screws somewhere safe.
C. Remove the top plate, place on a
non-scratch surface to prevent
marking.
You are now ready to replace the
valves or the fuses.
Valve replacement. We recommend
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the valves are replaced every 20,000
hours. This is conservative and per-
haps represents a two-thirds life
expectancy for these valves
in this design.
This amplifier is designed to use the
ECC82 (12AU7) valve only.
This valve type is very unlikely to go
out of production in the foreseeable
future. There are a number of manu-
facturers offering this valve. Spare
ASTINtrew valves can be purchased
through your dealer or distributor.
As a guide, using this amplifier four
times a week for an average four
hours a session, for 48 weeks a year,
we would recommended you change
the valves every 20 years. If you leave
your equipment switched on all the
time, then we would recommend
changing them every thirty months
(two and a half years).
Changing valves: Valves run HOT when
in use. Wait an hour after switching
the amplifier off before changing
valves.
The valve holders are attached to the
printed circuit board, and the spring
terminals that hold the valve pins are
strong, so care has to be taken not to
damage the board or valve when
removing or replacing them.
Do not pull or push the valve straight
into / out of the holder. This could
bend the circuit board and may result
in damage. The correct way to
remove / insert a valve is to pull /
push gently whilst rocking slightly in a
circular way (do not twist).
Remove by sliding, the white teflon
valve dampers from old valves and fit
on new valves in same position, near
top of valve.
When inserting a valve, first ensure
the pins are not bent on the valve.
Locate the pins onto the valve holder
correctly by aligning the ‘spacing posi-
tion’ on both valve and holder.
Changing the internal fuses: The fuse
holders and fuses are located close to
the valves on the circuit board. Only
replace with a 20mm glass 2 amp
and 5 amp slow-blow fuses, as indicat-
ed on printed circuit board.
When finished, ensure no items such
as tools or other parts are left in the
amplifier, replace the top plate, noting
the front and back screw positions are
different, re-fit all 10 Alan screws.
Take care not to over tighten and
damage the screw head or key.
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8. Troubleshooting
If the amplifier fails to work or you sus-
pect it is not working properly, first
check all connections to and from the
amplifier. Check all the simple and
obvious things first: power supply is on
at wall, pre-amplifier and source com-
ponents are switched on and working;
loudspeaker cables are fitted and
secured at both ends.
Below are some common problems,
with suggestions for the possible cure.
The list is not exhaustive. If you can-
not resolve the problem yourself,
please consult your appointed
ASTINtrew dealer or distributor.
No power:
Check all power switches are on and
power cable is secure in the back of
the amplifier. Remove power cable
from the amplifier and check the
mains fuse, located in the mains input
socket moulding.
No output:
Check there is a signal to the power
amplifier. Re-check cable connections
to the loudspeakers.
No output from one circuit:
Check all signal cables for that chan-
nel. Remove power cable from amplifi-
er and check internal fuses, adhering
to the instructions given in section 7.
Audible hum:
Check the components earthing in
your hi-fi system. Discuss with your
Dealer or supplier.
Poor stereo imaging and lack of
base output:
Check polarity of speaker connections,
particularly if you are bi-wiring.
9. Specifications
Designation:
AT5000 Dual mono power amplifier
Stereo power output:
50W RMS per channel (140W peak to peak) into
8 ohms
95W RMS per channel into 4 ohms
Power supply:
2 x 300VA Low noise Toroidal Transformers
Frequency response:
+ - 0.2 db 20-20,000 hz
Total Harmonic Distortion: 0.1
Input sensitivity: 610mv
Input impedance: 47K
Signal to noise ratio:
95 db A weighted
Internal fuse ratings:
2 amp and 5 amp slow blow 20mm glass
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C. Injury, loss or damage to persons,
proprty or products not covered by
this Guarantee.
D. Liability for damage or loss during
transit from the retailer or purchaser
back to ASTINtrew or its authorised
agent for the purposes of repair or
inspection.
Carriage costs to ASTINtrew shall be
borne by the consignor.
If the returned equipment is found not
to be faulty, ASTINtrew reserves the
right to make a charge for both the
examination and return carriage.
This guarantee does not affect your
consumer rights under English law.
11. CE, RoHS and WEEE
All ASTINtrew products
comply with CE regula-
tions.
When implimented into
UK legislation, all ASTINtrew products
will comply with the European RoHS
Directive.
When implimented into UK legislation,
all ASTINtrew products can be
returned after use in accordance with
the WEEE Directive. Contact your
Dealer for further information.
Valve
1 x ECC82 (12AU7) per channel
(20,000 hrs recommended replacement period)
Note - Output devices can withstand short
circuit indefinitely, but not recommended.
Mains voltage:
220-240V at 50Hz. UK, mainland
Europe and Asia.
AT5000 Dimensions:
W 430mm D 340mm Ht 110mm inc. feet.
Boxed weight: 15.5 Kg.
ASTINtrew reserves the right to make improve-
ments or changes which may result in specifica-
tion or feature changes without notice.
10. Guarantee
A two year guarantee is valid from the
data purchase, against any defect in
materials or workmanship. Retain your
reciept as proof of purchase. All
claims should be made through your
dealer or distributor
under this guarantee.
The guarantee excludes:
A. All damage caused by accident,
misuse, neglect, incorrect installation,
adjustment or replacement of valves,
non-authorised repair or service.
B. The Valves.
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