Theatre Design & Technology - Summer 1983 - 34

Both master and slave units are contain·
ed in rugged but light·weight aluminum chas·
sis, finished in a non·chippable urethane. The
cases are 12" wide, 7·Y.." deep (with connec·
tors). and only 1·Y," high to conserve valuable
rack space. Optional "ears" are available for
EIA 19" rack mounting. All connections (in
and out for four microphones per unit) are
hree·pin XLR. A line cord is supplied for 110/
120 V.AC. connection. The Crown units do
not include an on/off switch, but show power·
on status through a front panel LED.
The PH·4 system should improve micro·
phone performance in many set·ups, since a
full 48 volts is available to provide the power
needed for optimum dynamic range with all
kinds of microphones. Non·PZM mikes can
be connected directly to the PH·4 and PH-4S,
but Crown PZM microphones require the
Crown PXT impedance·matching accessory
for proper operation.
For more information, and for a tutorial
brochure on PZM microphones, contact
Crown International, 1718 West Mishawaka
Rd., Elkhart, IN 46517.

ew MT-C Power Amp Series
From Bogen
Three new, energy·saving power ampli·
fiers now are available from Bogen Division of
Lear Siegler, Inc. for sound reinforcement and
paging systems. In addition, the unique MT·
C Series is designed for life safety. security
and all other applications that cannot permit
interruption, even because of breakdown in
AC power transmission.
Models MT-60C, MT-125C and MT-250C
deliver rated power of 60 watts, 125 watts and
250 wa ts. respectively. They will deliver his
power con inuously for a period of 250 hours
or more, as proven hrough endurance testing
by Underwriters Labora ories.
The T·C Series has he Irs amplifiers
ever U.L.·lls ed for Fire PrOlec ive Signaling
Systems under that laboratory's ne', Sian·
dard for Safeiy. UL 480 They also fu 'ill he
atlonal F re Protection Assoclatlon's Sian·
dard for emergency communica ions sys·
tems. As he standard recommends
T·C
ampll lers can ooera e 'rom a 2L,vOli batter.
back·up source \'Ihen orlmary oower ;a s
A battery·saver clrcuii reduces Id'e cur·
rent 0 a lov: value (55 mAl after a minimum
of 20 seconds of no Signa
Solid·stale elecrronlcs Include c rcull pro·
tectlon. A LED InOlcates overloao conditions.
the arrollfler automatically shuts dovill until
the condition IS corrected

Specifications are available from Bogen
upon request. Contact: Bogen, P.O. Box 500,
Paramus, NJ 07652.

Wireless Manufacturer Announces
New Cabled Intercom Line

Smallest Professional Wireless
Microphone Has Highest Dynamic
Range
An all·new professional hand·held wire·
less microphone combines the Shure SM85
cardioid condenser element with the smallest
9·volt powered transmitter available. No sac·
rifice in battery availability or life was made:
a readily available 9·volt alkaline battery will
provide eigh hours of continuous life at 50
milliwatts of radiated power.
The eleven ounce HME System 85 trans·
mitter/element combination is less than nine
inches in length, shorter than a standard
SM85 plus cable connector. The HME trans·
mitter/receiver link is so transparent that
Shure Brothers Engineering tests have veri·
fied the audio output as being identical in all
respects to the SM85 element. The dynamic
range of the System 85 is over 115 dBA.
greater than that of the element itself, and the
highest value in the industry.
A totally silent "mike mute" switch en·
abies the talent to turn off the audio without
breaking the RF link. An advanced squelch
circuit prevents audible RF "dropouts" as
well as unwanted "pops" when the transmit·
er is turned off.
Con act: R. Dale Scott. General Sales
Manager. HM Electronics Inc., 6151 Fair·
mount Ave .. San Diego. CA 92120: (619)
280·6050.

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HM Electronics, Inc., the largest manufac·
turer of wireless microphones and wireless in·
tercoms, has introduced the first four pro·
ducts in its new line of cabled intercom sys·
tems. Called the 700 Series, the present offer·
ings include two multi·station power supplies,
a two·channel power station, and a belt pac
remote station, plus several accessory items.
The power supplies and power station in·
corporate fully· regulated 24 VDC power sup·
plies, which provide current·foldback protec·
tion for shorted audio cables, combined with
step·saving automatic reset when the fault is
cleared. The system components are fully
plug·compatible with existing 3'wire cabled in·
tercom systems as well as the HME 150E
series wireless intercom.
A unique soft·limiter allows undistorted
audio performance during high·level opera·
tion, an intelligibility advantage over com·
petitlve systems in high ambient noise situa·
tions. A special presence peak in the audio
frequencies provides clear voice transmission
without the ear fatigue usually associated with
this feature. Higher power supply current out·
puts, coupled with lower belt pac current
drain, is said to permit the use of more HME
belt pacs that competitive systems.
Contact: R. Dale Scott. General Sales
Manager, HM Electronics, Inc, 6151 Fair·
mount Ave .. San Diego, CA 92120: (619)
280·6050

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I) Vibration \leasurement and Analysis for
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\lachine Health \lonitoring.
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2) Vibration Isolation and Seismic Restraints * * * * * *
for Building \lechanical Equipment in
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Earthquake Zone;,.
3) Elcctro-acoustics for the Performing Arh. * * * * * *
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For further information please \\ ritc Box :"0. * * * * * *
-16256, Postal Station G. V.-\NCOLJ\'ER. Canada,
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\'6R -I .6.
ACOUSTICS WEEK 1:\ CA:'IADA

The Canadian Acou tical Association i holding its
Annual Symposium in Vancou\'er, Canada during
the week of October 1 th. 1983. In addition to the
general ession, the following eminar \\ ill be held:

CSITT Summcr 1983 Thealre De;,i!(n & Technol()g~

33
Table of Contents for the Digital Edition of Theatre Design & Technology - Summer 1983
