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icon Audio
Instruction Manual Covering:
MB90 mono block
Amplifier
Contents
1 Introduction & Final Inspection
2 Quick Set Up Guide
3 Connecting inputs & outputs
4 Getting the best performance
5 Trouble Shooting
6 Bias Adjustment
7 Valve Replacement
8 Specifications
9 Guarantee
10 Packing Instructions
1 Introduction
Thank you for purchasing the
MB 90s
.
These pure valve mono block amplifiers are the
result of years of careful design and listening tests
with a huge range of speakers. The amplifiers are
hand built using carefully selected audiophile
components. The transformers are hand would
using low oxygen copper and special Japanese
long grain iron. Finally each amplifier is valved,
carefully commissioned and tweaked for best
performance in Leicester UK.
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.
Hi fi reproduction is a long chain of events that
includes the recording, editing, mixing etc, before
being transferred to a medium such as LP, CD, or
FM, before being played through your own source
unit, the amplifier and finally loudspeakers.
Your room acoustics will also affect the sound
before it finally reaches your ear. Whilst the
amplifier is arguably the most important part of a
system, it is important to remember that the
weakest link will always affect the final results
when making judgements. And 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. Therefore setting up and
judgements s
hould be made with a ‘clean’ well
balanced recording.
The
MB 90
is a push-pull Ultralinear stereo
power amp, capable of running in either
Ultralinear (half pentode and half triode) or pure
triode mode, using the excellent KT90 valves.
These are in fixed-bias mode which whilst rarely
requiring attention gives maximum power, cool
running and wear indication. The driver and phase
splitting is all triode for best sound quality and low
noise. They are sensitive enough to be used with
all modern source equipment having an output of
400mv or greater. Their simplicity coupled with
point to point hand wiring without the use of
printed circuit boards results in an open euphoric
sound that is wonderfully detailed and warm.