Safety Instructions
1. Warning:
To reduce the risk of electric
shock, do not remove screws, cover or
back of the product as there are no
user-serviceable parts inside.
2. Caution:
do not operate the amplifier
near any fluids such as vases, beverages
etc.
3. Ventilation:
ensure the Medusa is in a
well ventilated position. It should not
be placed in a sealed cabinet or similar.
4.
If a good quality surge protector is not
employed, the unit should be
unplugged from the power point in
times of electrical storms and
lightning.
1.
Power switch: Press in to turn on the
power; Press again to turn off.
2.
Input select (Line 1, Line 2, Line 3,
Balanced, Phono)
3.
Volume control
4. Minijack input (Line 3, for portable
devices)
5. Direct Power Amp mode indicator
(when using a separate pre-amp)
6. Volume Unit meter
4
5
2
3
1
To bias valve 1
Switch amplifier on and allow it to warm up.
1.Turn bias setting knob to V1
2.Using a small screwdriver adjust the trim pot
labelled ‘V1 Bias Adjust’ until the meter reads
28mA (recommended
for KT88 valves) or
30mA (recommended
for KT120 valves if you
have installed them)
Repeat this procedure,
setting the control knob
to V2, V3 and V4 in
turn.
Front panel and controls
Adjusting the valve bias
Correct valve bias
makes a big difference
to the quality of your
sound, and the life of
your valves. If the
current is too high the
valves will run hot,
reducing their life span.
If the current is too low
the sound may be thin
and lacking volume.
Many valve amp
owners prefer to set
the current slightly low.
Medusa booklet layout_Layout 1 20/01/16 5:16 PM Page 2
