January 1955 Popular Electronics
Table of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
published October 1954 - April 1985. All copyrights are hereby acknowledged.
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. It appeared in the January 1955 issue of
Popular Electronics magazine (which had just begun publication four months
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
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.
Martin Bender (right), designer, plans wiring and installation
with Planetarium staff.
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.
The new control console after installation.
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
Posted August 10, 2022
(updated from original post