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icon Audio
Instruction Manual Covering:
Stereo 40 MK III all models
Pictured with SG KT88 valves
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 40 MKIII
. A
great deal of care has been taken in the design,
selection of components and production of this
amplifier. We are sure that you will hear the
difference.
In order to get the best out of your amplifier,
please read the enclosed notes. Even if you are
experienced with hi fi
please read the ‘quick set
up guide’.
Should you be uncertain about
anything to do with 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. Your ears will
have become accustomed to your old amplifier.
Sometimes 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 final results
when making judgements. Not all recordings are
‘equal’! Therefore an amplifier which faithfully
reproduces the input signal will also reproduce
imperfections in the tonal balance and the
recording itself. Setting up and judgements should
be made with a ‘clean’ well balanced recording.
The
Stereo 40 MKIII
is a push-pull Ultralinear
stereo power amp, capable of running in either
pentode ultralinear or pure triode mode, using the
excellent EL34 or KT88* valves in fixed bias. The
driver and phase splitting is all triode. The pre-
amp is a high quality ‘Passive’ circuit using silver
audio cable and an ALPS ‘blue’ volume control. It
is sensitive enough to be used with all modern
source equipment having an output of 250mv or
greater. Its simplicity coupled with point to point
wiring hand wiring without the use of printed
circuit boards results in an open euphoric sound
that is wonderfully detailed and warm sounding.
also covers the SE & ‘ie’ model, where the
tape monitor facility & triode circuit and are
omitted. *This model may be used with either
EL34/6CA7/KT77/KT66/KT88/6550
