Vol. 2, No. 8
Shure Brothers Incorporated
222 Hartrey Avenue
Evanston, IL 60202-3696
(847)866-2200
AMS In California State Senate
One of three California State Senate Committee rooms recent & equipped with AMS.
WAH Systems uses AMS24 microphones in all three Committee rooms.
At each microphone, a lighted pushbutton indicates “system-on” status.
WAH Systems Corporation,
Sacramento, CA, recently completed an extensive renovation of
the antiquated sound systems in
three committee rooms of the
California State Senate.
According to WAH, the Senate
contract presented several interesting problems and offered a
unique opportunity for demonstrating the company’s turnkey
approach to AMS installations.
The project involved the use of
80 channels of AMS employing
AMS24 microphones, 56 channels of distributed audio, 58
speakers, 43 intercom stations,
and over six miles of wire. Signal
paths and termination panel layouts were designed, optimized,
and tested by WAH with an Apple
Macintosh computer.
The basic component of the system is WAH’s specially designed
microphone/speaker panel, even
though the project required several variations of the basic unit.
Most variations consisted of a
Shure AMS24 gooseneck microphone mounted adjacent to a
Soundolier FC104 speaker. The
speaker is positioned underneath
a perforated section of the panel.
A pushbutton switch located
next to the microphone lights up
softly to indicate system-on status.
When a senator pushes the button
to activate his individual microphone to “ready to speak” status,
it glows brightly. The panel in front
of the Committee Chairman has
an additional button which mutes
all other AMS microphones in
the system.
(Continued on Page 2)
AMS in California State Senate
(Cont’d from Page 1)
According to Walter Horsting,
president of WAH Systems, “the
senators are very much accustomed to having a mic in front of
them, so the low-profile appeal of
the AMS22 didn’t seem warranted
in this application. And, since the
sound of shuffling papers has more
of a disruptive effect on a surfacemount mic, we decided to go with
the AMS24 gooseneck version."
A subtle feature of the installation can be found in the panel’s
speaker circuit. In many AMS installations, a loudspeaker will
automatically mute when the corresponding mic gates on. WAH
engineers observed that when a
speaker is muted completely, a
disconcerting change occurred in
the perceived sound field at the
open-mic position. By utilizing a
relay-operated switch to change
taps on the 70-volt speaker line,
WAH obtained a 3 dB drop in
loudspeaker output-enough to
avert any possible feedback problems without completely muting
loudspeakers.
In addition to panel mics, each
committee room has four to six
panel modules which can be placed
on witness tables facing the dias.
Each panel is a duplicate of the
basic design minus the loudspeaker, and is encased in a
WAH-designed fluted solid wood
pedestal. Cherrywood timber was
used for the milling of parts for
the pedestals, the manufacturing
of which required that a special
shaping blade be fabricated.
The role of the Senate Sergeantat-Arms required particular attention. During a committee meeting,
the Sergeant-at-Arms is charged
with providing complete security
and control in the room, while
serving as liaison for any communication from the outside to
the committee members during
the meeting. In addition, he must
make sure that every meeting is
properly recorded on audio tape.
Before the recent renovation, the
sound equipment was located in an
adjacent room and the Sergeantat-Arms had to leave the committee room to initiate any system
status changes. WAH solved the
problem by designing a master
workstation that would allow the
Sergeant-at-Arms to perform all
of his duties without leaving his
post. Our thanks to Ken Fitzgerald,
Deputy Chief Sergeant-at-Arms,
California State Senate, and
Walter Horsting for providing this
Update story.
AMS Enhances Appearance of
Norwegian Prime Minister’s Conference Room
The centerpiece of the strikingly
modern conference room of the
Prime Minister of Norway is an
oval table fitted with 20 AMS24
microphones. The Oslo installation, w h i c h i n c l u d e s t h r e e
AMS8000 mixers plus an AMS28
lavalier microphone, is used for
general sound reinforcement and
recording.
Because of the originality of the
decor, it was necessary for the
microphones to blend in unobtrusively, and the AMS24’s do the job
admirably, actually enhancing the
room’s aesthetics.
This conference room system
was installed by System Teknikk
A/S, Oslo.
Norwegian Prime Minister’s
Conference Room
New California Installations
City of Fremont Council chambers
Steve Thorburn of Charles M.
Salter & Associates recently
sent us information on two interesting AMS installations in California of their design.
One is an audio/visual system
at the Fremont City Hall council
chambers, Fremont, CA. The system provides video monitoring and
sound reinforcement for council
room events, while providing a
broadcast-quality uplink to the
local community cable television
network system. A total of 16 AMS
microphones, with mute switches
and indicators, are located at the
mayor’s position, each staff position, each council/commissioner
position, the lectern, and the
clerk’s desk. The AMS880 is also
used to control a video switcher
which routes the video signal to an
archival recording system.
The Fremont system also incor-
Modesto Irrigation District room
porates a distributed loudspeaker
system for sound reinforcement
and a playback system for audio
and video cassette tapes and
AM/FM radio broadcasts. Other
features include a cable system
demodulator, a headphone listening
system for the hearing impaired,
and a cable system feed to the
uplink modulator. Ceitronics of San
Jose, CA installed the Fremont
system.
The second installation is a
boardroom A/V system at the
Modesto (CA) Irrigation District
Facility. This 16-channel AMS system utilizes the AMS880 Video
Switcher Interface to allow video
cameras to automatically follow
council debate.
The system provides sound reinforcement of the board, podium,
and secretary discussions, plus
video recordings of proceedings.
New A24QG Makes
AMS24 Removeable
The new Shure model A24QG
is an accessory conversion kit for
use with the AMS24 gooseneck
microphone. When properly installed, it permits the AMS24 to
be used as an easily disconnectable XLR connector mount instead
of the threaded flange mount provided with the AMS24.
The A24QG consists of a black
metal case with an internal 5/16”24 thread in one end and a male
XLR connector in the other which
mates with a 3-pin female XLR receptacle. The A24QG has a user
price of $35.00 and is available
immediately.
A24QG
The council chamber of the
town of Vaughan, Ontario is now
home to an impressive 24-channel
AMS installation featuring three
AMS8000 mixers, ten AMS24
microphones, and four AMS26
microphones.
Each microphone position features a custom plate with privacy
switch, LED indicator, and XLR
connector for easy microphone
removal. The chairman/mayor’s
desk includes an extra custom
plate with LED and switch for use
by guest speakers. The chairman’s
position also has an overall muting switch while the clerk’s desk
has an input for the recording of
meetings.
This installation was done by
KDM Electronics, Inc., Scarborough, Ontario. Thanks to KDM’s
Tom Bandini for the information.
State Of The Art
Mock Courtroom
The law firm of Phelan, Pope, and
John now boasts a state of the art
AMS installation in their unique
mock courtroom. Located on the
42nd floor of the new 311 S.
Wacker building in Chicago, the
mock courtroom provides the kind
of media center law firms will need
to remain competitive in the future.
This system is used to simulate incourt conditions, serving the needs
of both attorneys and litigants.
Twelve channels of AMS (one
AMS8000 and one AMS4000)
are used to provide the microphone mix for the entire system.
AMS26 microphones are employed for all fixed microphone
positions and are mounted on custom anodized mic stands. In addition, there are three wireless
microphones for the attorneys,
each of which use an RKC190
AMS wireless interface.
Sound reinforcement for both
the courtroom and the adjacent
conference room is provided by 16
New Installations
And Upgrades By RFI
Don Jenkins of RFI, San Jose,
CA, recently sent us information
on three AMS installations handled
by his company.
One is the headquarters of
PERS (Public Employees Retirement System) of California, located
in Sacramento. This recording/
reinforcement system currently
includes three AMS8000 mixers,
one AMS4000 mixer, 13 AMS24
gooseneck microphones, and four
AMS22 low-profile microphones.
A Crestron Media Control System
and IDEC Programmable Controller System are connected to the
AMS logic terminals for mic control. Mic zone availability can be
controlled from the clerk’s position
at the staff table or from the control center. Each AMS mixer Aux
Out is attenuated to mic level to
match the recorder input.
Another of RFl’s AMS installa-
Printed in U.S.A. 2/91
Technical Q&A
ceiling mounted loudspeakers on
a 70 volt distributed line. The output of the AMS goes into a Shure
M267 where it is combined with
taped audio sources for playback
through the reinforcement system. Four camera locations videotape the proceedings. Recording
the entire proceedings are two
VHS recorders and two audio cassette recorders.
Our thanks to Cindy Kazan, public relations director for Phelan,
Pope, and John for providing the
information on this system. RC
Communications of Schiller Park,
IL designed and installed the
system.
tions is located in the Cupertino,
CA city council chamber. This is a
16-channel system incorporating
two AMS8000 mixers, five
AMS22 mics, and 11 AMS26
mics. This system, which provides
sound reinforcement in the council chamber, is also connected to
a television production facility
located in the basement of the
building.
RFl’s third AMS installation is a
20-channel system in the City of
Sacramento council chamber.
This system, incorporating two
AMS8000’s one AMS4000, 16
AMS24’s, and one AMS28, is an
integral part of an elaborate sound
reinforcement and cablecasting
installation.
Don Jenkins served as project
engineer on all three projects.
Others involved with one or more
of the projects include technicians
Gregg Minolli, Chris Masin, Bernie
Carrasco, and Roy Bernstein, and
project managers Gene Mendoza
and Mark Day.
Do you have any suggestions for
remote volume control of AMS
installations?
There are a number of products
on the market designed for this
kind of application. Products that
have come to our attention recently
include- the Oxmoor OCA-2 Control Attenuator and RC-16 Remote
Control, and the Pro Tech Audio
668VCA Voltage - Controlled
Amplifier. Although we have no
direct experience with these products, their specifications indicate
an ability to do the job, and you
might consider checking them out.
For further information, the phone
numbers are: Oxmoor Corp. (205)
942-6779, Pro Tech Audio Corp.
(516)584-5855.
Where can I get audio cable that has
a shielded pair for the AMS mic, plus
an unshielded pair for logic controls,
all in the same cable jacket?
Try GEPCO International, Inc.
in Chicago, a provider of cable
products for professional technicians. Their phone number is
13121733-9555.
Back Issues of
AMS Update
Available
If you missed previous issues
o f AMS Update, they may be
obtained by contacting Michael
Pettersen at Shure and requesting the issues you want:
AL936 -Volume 1 Compilation
AL928 -Vol. 2, No. 1
AL951 -Vol. 2, No. 2
AL965 -Vol. 2, No. 3
AL996 -Vol. 2, No. 4
AL1010 -Vol. 2, No. 5
AL1034 -Vol. 2, No. 6
AL1035 -Vol. 2, No. 7
AL1081