When a center-channel output has not been designed Into a unit, it can be created by the
Spacexpander. (See Fig. 7, previous page). Any output jacks for a stereo tape recorder can be used
as the signal source for the Spacexpander Inputs. A power amplifier and a speaker are needed to
complete the center channel. The Spacexpander output cannot drive a speaker directly. It must be
connected to a power amplifier, which. in turn, is connected to the speaker
The tape recorder signal input plugs are then inserted into the other pair of input jacks on the
Spacexpander panel. The jacks for both A INPUTS and both B INPUTS are wired together, inside the
Spacexpander, and the tape recorder will record the normal signal, without reverberation just as
it did when connected to the jacks on the high-fidelity instrument chassis. The material recorded
will not have reverberation added to it when you connect to these jacks Reverberation is added
after this point.
FINISHING THE INSTALLATION
No matter which electrical connections are best suited to your home music system equipment, and
your personal listening habits, the physical mounting of the Control Unit, Electronics Chassis and
Reverberation Chassis remains the same.
The most convenient mounting locations for the Electronics Chassis and the Reverberation chassis
may not be the best physical location for these units. While the Electronics Chassis may be
mounted in any position it is best to mount it with the tubes at the top. This way the heat will rise
away from the chassis, reducing the possibility of overheating the chassis and damaging any of
the circuit components that are wired inside.
Wherever possible the AC power cord should be plugged into an outlet on the home music system
equipment - an outlet that is turned on and off by the same power switch that controls the whole
system. Accidentally leaving the Spacexpander on for many hours will only shorten its trouble-
free life and cause the tubes to burn out sooner than necessary. The on-off switch on the Control
Unit does not turn off the AC power to the Spacexpander - it only stops the reverberated signal
from being amplified. The pure (not reverberated) signal still is amplified by the Spacexpander
circuits.
The reverberation Chassis must be mounted against a vertical surface This unit is an electro-
mechanical device and its exact mounting is very critical (For a more complete explanation of the
method of operation of this critical mechanism read the section on HOW YOUR SPACEXPANDER
WORKS.). Not only is the position of the Reverberation Chassis critical - so is its location.
It is subject to mechanical vibration - DO NOT mount it near the speakers The vibrations from the
speakers can vibrate the mechanical portions of the Spacexpander which, in turn, will be
amplified and heard from the speakers whose vibrations again will be picked up by the
mechanical portion of the Spacexpander and amplified This feedback quickly becomes a howl,
screech, whistle or groan, depending on how slowly or how rapidly the vibrations get back from
the speakers. Generally this effect will occur only when the Reverberation Chassis is mounted on
the back of a console cabinet - and then only when the instrument is played at high volume.
Component-type high-fidelity systems seldom
have mechanical feedback problems since the
speakers are usually separated from the
electronic equipment.
When property installed, the Reverberation
Chassis will float on the shock mounts and, under
normal conditions there will be no feedback. DO
NOT over tighten the wood screws through the
grommets, when mounting the Reverberation
Unit. Leave some freeplay - 1/32 inch is enough
Compressing the grommets reduces the
effectiveness of the shock mount assembly by
being too firm.
