Quicksilver M135 User Manual

Quicksilver Audio M135Mono Amplifier

Operating Instructions

Thank you for purchasing the Quicksilver Audio M135 Mono Amplifiers. These amplifiers have been engineered to
have a very wide bandwidth, extremely low distortion and superior dynamic range.

The output transformer used in this amplifier is based on the best designs of the past but uses superior new materials
to achieve a very high level of performance. The high frequency characteristics of this transformer are so stable that
many different output tubes may be used without the need for circuit changes or compensation adjustments.

The front end circuitry used in this amplifier was developed by Quicksilver and is unique to the audio industry. It is
D.C. coupled for low frequency stability, and nulls out any change in power supply voltages, negating the need for
regulated power supplies and their inherent sonic problems.

This is an all tube design and uses no circuit boards or transistors.

This device has very high internal voltages. Never operate with the bottom removed!
Never operate your amplifers with the speakers disconnected.
To prolong the life of your amplifiers, never turn them on and off within a short period of time
(45 seconds.)

PLACEMENT

The M135 Mono Amplifiers should have at least 6 inches of ventilation space on either side and
at least 10 inches above them. If this is not possible, then use a fan for cooling.

SPEAKER CONNECTION

Five-way binding posts are used for speaker connection. For better sonic performance, we
recommend using the screw-down part of the post rather than banana plugs to connect your
speaker wire. Make sure the leads do not touch each other. The rating on the back of your speaker
system will determine whether you use the 4 or 8 ohm tap.

INPUT
100K

4Ω 8Ω

Power cord

Fuse

Serial Number Plate

SYSTEM GROUNDING

Your Mono Amplifiers come with three pronged grounded AC plugs. In some systems, where the
preamp is also grounded, a ground loop may appear as a low level hum. Using an adaptor on the
AC plug, to lift the ground, will solve this problem.

4 AMP SLO-BLO FUSE

Standard fuse value must not be exceeded. If a fuse blows, replace and check output tube bias.
If there is a large change in any tube, then that tube is probably damaged. If the bias has not
changed then the cause of the fuse blowing may be due to other problems, such as poor system
grounding, unstable preamp, shorted speaker, etc. Interchanging the amps between channels will
help localize the problem to either the system or the amplifier.

TUBES

The input tubes in this amplifier were chosen for their specific performance characteristics. These
tubes should last several years or many thousands of hours. We can only guarantee the
performance of this unit when used with input tubes supplied by Quicksilver.

Quicksilver ships the M135 Amplifiers with matched EL34 output tubes but the M135 can use a
variety of output tubes. The output tubes do not need to be matched however matched tubes can
provide better performance.

Output tubes will need to be replaced periodically. When a degradation in sound occurs, the fuse
blows repeatedly or the tubes will not hold their bias anymore it is time for new output tubes. We
recommend purchasing tubes from Quicksilver Audio or your dealer and we recommend keeping
an extra output tube on hand in the event that one fails.

OUTPUT TUBE BIAS SETTING

Output tube bias should be set immediately when new tubes are put in; then again in 15 minutes;
and periodically the first few times of using the amplifiers. After that the bias should be checked
monthly.

The bias must be set correctly for the type of output tube that is used. The maximum setting for each
tube is as follows:

EL34 45ma
KT77 50ma
6L6 50ma
6550 60ma

KT88 60ma
Bias controls are behind the door near the right front panel handle. Open the door by applying
pressure with a finger at the bottom right. To check the bias push in the control for the tube you
want to check. Each tube corresponds to the control nearest it.

To adjust the bias you will need a slot-head screwdriver. Adjust by turning clockwise to increase
bias; counterclockwise to decrease bias. Do this for each of the six output tubes. Actual bias is
shown on the front panel bias meter. The M135 can use a variety of output tubes. Remember that

bias set above the recommended values will wear out your tubes prematurely.

If you depress two or more jacks at the same time the meter averages the readings of the tubes,
so your meter will not be damaged. Tube biases should be checked individually.