Hammond Model A, Manual, Page: 44 / 298

REVERBERATION SYSTEM
A-l00
To the left of the amplifier are the reverberation amplifier and reverberation unit.
A portion of the output signal of the power amplifier passes through the
reverberation unit to the reverberation amplifier and this drives a third 12"speaker
housed within the console. The degree of reverberation heard can be regulated by
rotating the knob marked Reverberation Control located above the Vibrato tabs on
the left side of the console.
D-100
To the left of the pedal solo generator is the Hammond Reverberation unit. Signals
from the preamplifier are applied to the treble with reverberation channel
of the power amplifier and are heard from the 8" speaker located to the right
of the player.
In operation, an electrical signal from the reverberation drive channel is applied
to the driver unit in the reverberation device which then converts the
electrical signal into mechanical energy. This energy is transmitted through
springs to a pickup unit where a part of it is converted back to electrical
energy. The remaining portion is reflected back to the driver and again back
to the pickup at a time interval determined by the spring lengths. This transaction
continues until the signal energy is reduced to one millionth of its original value.
The transfer time from driver to pickup and the reflections within the system itself
produce the reverberation effect.
The degree of reverberation heard can be regulated
by rotating the knob marked Reverberation Control shown in Figure 5.
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