January 1955 Popular Electronics
Table of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
from
Popular Electronics,
published October 1954 - April 1985. All copyrights are hereby acknowledged.
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Audiophiles of the 1950s undoubtedly were impressed
by the mention of a Rek-o-kut twin turntable with Pickering arms and pickups for playing records, let
alone a twin Ampex tape system used both for recording and reproducing. That was awe-inducing stuff
for the day, especially when applied to a planetarium show with visual and sound effects realistic enough
to , "make adult members of the audience duck under their seats." We don't scare so easily these days.
Here is the story of New York City's famous Hayden
Planetarium after the marriage of the aforementioned sound and control system with its legendary
Zeiss star projector.
Hi-Fi at the Planetarium
New electronic equipment provides breathtaking realism of sight and sound in famous "theater
of the skies."
Mr. Joseph M. Chamberlain
(left), Chief Astronomer of the Planetarium, at the new control console.A mammoth electronic control
console has been installed in New York City's famous Hayden Planetarium, Synchronizing the Planetarium's
Zeiss Projector with an elaborate high-fidelity sound system, the console enables the "theater of the
skies" to present its shows with startling realism of both visual and aural effects.
The only instrument of its kind in the world, the new unit, as well as the entire sound system, was
designed and installed by the Altec Service Corporation of New York, with Mr. Martin Bender, Commercial
Engineer attached to Altec N.Y., supervising the entire operation, and Mr. Joseph M. Chamberlain, Chief
Astronomer of the Planetarium, contributing to the guidance and scope of the program of improvement.

Hi-fi record and tape equipment, amplifiers, and controls are housed in soundproof
room.

U.N. children saw home skies protected.

Altec and Planetarium technicians took six days to install the new unit.

Martin Bender (right), designer, plans wiring and installation with Planetarium staff.
Almost a mile of wiring is used in the unusual instrument, as well as dozens of switches, knobs,
relays, circuit breakers, and other components. The unit weighs 1500 pounds and took a year to design
and build. Now in operation, it is capable of controlling 96 different combinations of special effects
to enhance the theatrical possibilities of the Zeiss Projector. In addition, it controls any sequence
of 15 different lighting machines, each of which includes up to a dozen different scenes that may be
displayed. The resultant combination provides an almost fabulous range of possibilities for showing
celestial phenomena. Synchronization of these visual effects with specially prepared sound effects is
now so perfect, that the spectacle of a meteor hurtling toward the earth, accompanied by a terrifying
noise, is enough to make adult members of the audience duck under their seats.
The new control console is the climax of a five year program of improvement at the Planetarium, during
which time Altec also installed a complete audio system. Chief problem facing Mr. Bender in this task
was to diffuse correctly the sound in the dome-like room that is the Planetarium theater, as well as
in the cylindrical room in which lectures are given. In both rooms the shape and architectural material
worked against good acoustics rather than for it.
The dome, in which music and speech as well as special sound effects were to be reproduced, received
two speaker systems, each complete in itself with one woofer and two tweeters for maximum distribution
of high frequency sounds. One system handles music and sound effects; the other reproduces the lecturer's
voice and serves also as a standby speaker in case of failure of the former.
In the cylindrical room, the saturation method of speaker placement was used by installing a ring
of twenty-four speakers around the ceiling.
Feeding these speaker systems are audio program sources and input systems located in a studio-type
control room. In addition to the microphone used by the lecturer, the control room houses a Rek-o-kut
twin turntable with Pickering arms and pickups for playing records. Adjacent to these is a twin Ampex
tape system used both for recording and reproducing. All input signals are fed through Altec-Lansing
preamplifiers and output amplifiers. The system is rounded out with switching and patching panels that
provide maximum flexibility in feeding the sound to any or all parts of the speaker system as well as
in monitoring programs. Because the output frequency response of the system is flat, radio stations
can connect directly to any of the outputs and broadcast programs directly without correcting for local
equalization.
Speaker muting is provided at the control console permitting the lecturer to communicate with the
control room without the audience being aware of it. END

The new control console after installation.
Posted June 29, 2012
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