For a
dirtier
sound, the MASTER volume control enables the preamplifiers to be
overdriven without having the amplifier at full
volume.
Push the switch attached to the
MASTER volume control in to
activate
the circuit, then turn the control fully
counter-clockwise.
No sound will come from the amplifier at this point. Now turn the
volume control of the channel you are using fully clockwise or nearly so. Turn the
MASTER volume control
clockwise
until sound is produced from the speakers.
Experiment with the settings of both the channel volume control and the MASTER
volume control until the desired results are achieved. Remember, if the channel volume
control (on either channel) is
"cranked" up,
and the MASTER volume is turned down, an
over-driven sound is produced. Experiment with both controls simultaneously to
understand more fully how their interaction affects overdrive characteristics.
By using the Channel volume, Master volume and the Hi-Lo power setting
switch, a wide range of tonal spectra may be explored. Once again, let experimen-
tation be the mother of invention!
CUT:
The CUT control varies the bandwidth, or high frequency response of the power
amplifier. In the minimum or counter clock-wise position, the amplifier is at full
bandwidth. Clock wise rotation of this control
decreases
the bandwidth of the amplifier.
This is characterized by
fewer highs
or
less top end.
The CUT control is used to soften
or take the edge off a harsh instrument or tone setting. The effect is subtle before the
halfway point on the control and increases the amount of cut from midpoint to full.
The
CUT control is most effective when the Master volume is bypassed or set for
maximum gain.
MAINTENANCE:
Aside from routine vacuum tube and indicator lamp replacement, your
MATCHLESS should require very little in the way of maintenance. Periodically examine
the four output tubes visible from the rear of the chassis. Any tendency of one or more of
these tubes to glow
reddish
in the plate area is an indication of an imbalance in the
amplifier. This should be checked out by a technician or by substituting a fresh set of
matched output tubes. If over a period of time or hard playing the amplifier sounds weak
or dull, this may be an indication that the output or preamp tubes are
"tired"
and
probably need renewal. If one or more of the preamp tubes becomes abnormally
microphonic or the amplifier whistles with the controls at maximum (with nothing
plugged into the inputs) a replacement may be required. When replacing output tubes
remember that they are a matched set and should be replaced with a
matched set of
four.
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