Hammond Model A, Manual, Page: 166 / 298

ATTACHMENT OF EXTRA EQUIPMENT TO THE HAMMOND ORGAN
INPUT EQUIPMENT
The amplification system of the Hammond Organ may be used as an amplifier for a
microphone, record player, radio or television receiver, or FM tuner. However,
because the amplification section of the instrument is designed for use with the
Hammond Organ generating system, and because organ music is rich in low frequencies,
the bass quality may be abnormally emphasized when such devices are used.
It is sometimes assumed that a high-grade electric organ will necessarily have a
high fidelity sound system. This term, which refers to the ability to reproduce
sound accurately, has no meaning when applied to an instrument which originates its
own sound. Similarly, flat response, which is desirable in a reproducing system, is
not necessarily an advantage in an organ amplifier, where uneven response may be
incorporated intentionally to compensate for opposing variations in the generated
tones.
It should also be noted that reverberation, which is so desirable for organ music,
is less desirable with speech and with some types of music.
For the above reasons it may be found most satisfactory to provide a separate
amplification system, but the suggestions in figures 1 to 6 are furnished in case a
separate amplifier is not available.
NOTES IN REFERENCE TO FIGURES 1 to 6
The volume control shown in these drawings is required because the expression pedal
of the organ does not affect the volume of any attachments. If the record player or
microphone has a built-in volume control, no additional control is necessary.
The .0005 mfd. condenser and the 1 megohm resistor are a crystal compensating
network and should be omitted if any other kind of microphone or pickup is used.
The voice coil output of a radio or television receiver can be connected in the same
way, except that no additional volume control is required. In case the volume is too
low, it may be necessary to use a suitable step-up transformer.
The output of some FM tuners can be connected in the same way. A volume
control will be required if the tuner does not have its own.
If the organ is to be played at the same time, it should be turned on in the usual
manner. If the organ is not to be played, merely push the run switch
to the on position.
If the organ has a reverberation unit, it should preferably be turned off when using
phonograph or microphone.
Use care in shielding all connections and the volume control, in order to avoid
picking up hum. Make connecting leads as short as possible and expose as little of
unshielded wire as possible.
If the microphone or phonograph does not have enough signal voltage to give adequate
output, a microphone or phonograph preamplifier may be needed in addition.
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