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Page 6 

(b) Amplifier or speakers. 

Sound  will  not 

move. 
If  you  have  connected  both  a  known  good  input 
and a known good speaker to a particular channel 
without  success  the  fault  is  probably  within  the 
amplifier. 

 

Strange noises coming from speakers 

Turn  volume  to  minimum  on  unused  input,  if  the 
noise  disappears,  the  fault  is  with  the  source  or 
the  connection.  If  noise  persists,  the  problem  is 
with the amplifier. 

 

If  a  whole  output  valve  glows  red  (other  than  the 
heater), often accompanied by a hum through the 
speakers, switch off immediately, and refer to Icon 
Audio or a service engineer, as this could be valve 
failure. 

 

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 

(see also section 7) 

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. 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 
(the  KT88s  should  be  held  by  the  base  when 
removing,  to  prevent  damage)  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). 
 

Mains Supply 

This  amplifier  is  hard  wired  to  work  on  230/240v 
ac.  The  transformer  may  be  re-configured  for 
110/120v  ac  by  a  qualified  engineer.  Contact  for 
more information. 

6 Specification & Features 

(Typical conditions @ 240v 50Hz) 

 

KT88 output valves or eqv (6550) 

 

6SN7 double triodes for first stage 

 

274B (GZ34/5AR4) Full wave rectifier 

 

Hand wired point to point components 

 

No printed circuit board 

 

No tag board 

 

Ceramic valve bases for low noise/leakage 

 

HT delay circuit to protect cathodes (optional) 

 

19.5w RMS per channel Ultralinear (at clipping) 

 

Signal to noise level -90db 

 

Freq response 20-20kHz +or- 1db 

 

Power bandwidth 10Hz-30kHz 

 

0.2% THD @ 1w 0.5% @8w 

 

4 and 8 ohms output taps 

 

Japanese EI transformers 

 

Choke regulated power supply 

 

Supplied with attractive safety guard 

 

Minimal feedback used 

 

3 section transformer cover to reduce noise 

 

High quality metal film & wire wound resistors 

 

High quality polypropylene audio caps 

 

Japanese ‘Blue’ ALPS volume pot. 

 

Rubicon/Nichichron power caps. 

 

Internal wiring using silver gilt cable 

 

Valves carefully matched for best performance 

 

Gold plated Input & speaker terminals  

 

Inputs for CD, Tape, Tuner, Aux 

 

350 mv sensitivity for full output (integrated) 

 

1000mv  (1v)  sensitivity  for  full  output  (power 

amp) 

 

230/240volts, 135watts 

 

1.6 amp rear fuse (with spare) 

 

Size: W=40cm,D=32cm,H=25cm/Weight:17Kg 

 

IEC mains lead, (5amp fused) 

 

CE certified 

Specification subject to change without notice. 

 

Summary of Contents for Stereo 20 SE

Page 1: ...ifier which faithfully reproduces the input signal will also reproduce imperfections in the tonal balance and the recording itself Therefore setting up and judgements should be made with a clean well...

Page 2: ...min 6 hour test Check inputs Output Valve Bias level mv Sound Quality Channel Balance Valve Microphony Valve Seating Hum level left right mv RF Test LED brightness Serial No sticker and recorded Mains...

Page 3: ...fully anti clockwise there should be no sound coming from the speakers except a barely discernable gentle hum If there are any unpleasant sounds coming from the speakers switch off and refer to the Tr...

Page 4: ...h cable to fit in the connector and twist together to avoid any spare strands touching anywhere else soldering the stands together helps Be warned this amplifier does not have an output protection dev...

Page 5: ...ce life and maintain their performance longer The upgrade valves supplied with selected models are the result of careful comparison with other makes Cabinet Care To remove dust we suggest gentle brush...

Page 6: ...ou 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 properl...

Page 7: ...readings or you cannot set the 900mv then that valve is probably faulty or out of specification If you are unable to set the reading high enough this means the emission of the valve is low Replacing t...

Page 8: ...tic 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 9 Packing...

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