Page 6
A valve that is lit up is not a guarantee that it is
working properly; conversely a valve that is not lit up
will not be working.
Valve Replacement
No special procedure or set up is involved. Switch off
and unplug before attempting. As the valves used in
the Stereo 20 are easily available and reasonably
priced it is worthwhile investing in quality
replacements. Only fitted the designated types as
others may damage the amplifier and cause high
voltages to be present at the input terminals. We
would recommend that the EL84s and the 12AU7s be
replaced as sets.
Valve life will depend upon such things as hours of
use and number of on/off cycles, the HT Delay Circuit
if fitted will extend the life of the valve by not stressing
the cathode when it is cold. We would expect around
three years life, but valves may last considerably
longer than this although at reduced output. It is not
good practice to remove the valves unnecessarily as
this can strain the pins and cause tiny air leaks.
Service:
Should you suspect a problem, you could
return the unit to Icon Audio for a periodic service or
return the valves for testing free of charge. You
should carefully remove the valves numbering them
with a marker from left to right as you do so in order
that that may be replaced in the same position. They
should be well packed in cardboard & foam or similar,
and returned to Icon Audio for testing. (Valves are
very rugged if packed properly).
6 Specification & Features
•
4x EL84 output valves or equivalents
•
1x 12AX7 (ECC83) Triode for first stage
•
2x 12AU7 (ECC82) Triodes for phase-splitter
•
No printed circuit board
•
No
tag board
•
Ceramic valve bases for low noise/leakage
•
12AX7/U7 heaters floated at 60v to minimise
cathode leakage & noise.
•
HT delay circuit to protect cathodes (option)
•
Soft start fitted to protect vital components
•
All hand wired point to point method
•
15 Watts RMS per channel
•
Class AB operation
•
Signal to noise level -89db
•
Freq response 10-50khz +or- 0db @1w
•
Freq response 30-20khz +or- 1db @10w
•
4 to 8 ohms speaker matching (6 optimum)
•
Japanese EI transformers
•
Supplied with attractive safety guard
•
Minimal feedback used
•
Ultralinear
transformer
•
High quality metal film & wire wound resistors
•
High quality polypropylene audio caps
•
Japanese ‘Blue’ ALPS volume pot.
•
Black Diamond/Rubicon power caps.
•
Internal wiring using silver gilt cable
•
Valves matched & burnt in up to 100 hrs
•
Polished stainless steel chassis
•
Gold plated Input & speaker terminals
•
Inputs for CD, Tape, Tuner, Aux
•
250mv sensitivity for full output
•
230/240volts,
100watts
•
1 anti surge amp rear fuse. (plus one spare)
•
Size 300W, 250D, 180H, allowance should be
made for adequate ventilation.
•
Weight
8kg
•
IEC mains lead, (3amp fused)
•
CE
certified
(Typical, but may vary slightly with valves and mains voltage)
Specification subject to change without notice.
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 supplied packaging will provide essential
protection during storage shipping or service
return. It will probably also increase the second
hand value. We would suggest that this be retained
wherever possible.
Please use the supplied cardboard strip between the
valve cover and transformer cover to protect the
paintwork.
Do not write on box, but use removable labels.
icon Audio
UK LTD
351 Aylestone Road Leicester LE2 8TA
www.iconaudio.com
phone 0116 244 0593
mobile 07787 158791
Nov 2007 Dir version
