Bogen Car Amplifier GA6A User Manual

Utility Amplifier  
GA6A Model  
Installation and Use Manual  
© 2004 Bogen Communications, Inc.  
All rights reserved.  
Specifications subject to change without notice.  
54-5757-03B 0406  
 
Description  
The GA6A is a rugged six-watt, dual-input audio amplifier with a wide variety of smaller applications including  
background music, relaying communication from one room to another, or sound reinforcement.  
The GA6A delivers rated power at not more than 1% total harmonic distortion from 75-15,000 Hz into  
transformer-coupled or direct low-impedance loads.  
Inputs for a low-impedance balanced dynamic microphone and an auxiliary audio source (tuner, tape deck, etc.) can  
be mixed. Individual front-panel controls regulate the level of each input. Connections for 8-ohm and 25V or 70V  
speaker lines are provided on the rear panel output terminal strip. A 3-position switch is supplied to provide +9 dB  
boost, -9 dB cut at 10 kHz or flat response.  
Package Contents  
(1) GA6A  
(1) Installation and Use Manual  
Accessories  
WMT1A  
MatchingTransformer  
Hi-Z, 10k-ohm primary impedance  
Lo-Z, 600-ohm secondary impedance, balanced with  
center tap  
Matches high-to-low impedance or low-to-high  
impedance  
Adapts line level signals to microphone inputs  
3
 
Panel Descriptions  
Utility Amplifier Front Panel  
1. MIC Control - Regulates the level of microphone output to speakers.  
2. AUX Control - Regulates the level of the AUX source to speakers.  
3. Power Switch - Controls AC power to the amplifier. Illuminates when ON.  
Utility Amplifier Rear Panel  
1. Speaker Output Barrier Strip - Output terminal strip provides for 8-ohm, 25V, and 70V speaker outputs.  
2. Shorting Link - Used when 25V or 70V speakers are to be connected to the GA6A. Must be removed if  
8-ohm speakers are to be connected to the GA6A.  
3. MicrophoneTerminal - Input terminal strip for a balanced low-impedance dynamic microphone.  
4. AC Line Cord - 120V AC, 60 Hz, 0.15A line cord terminated in a three-prong plug.  
5. Treble Control Switch - A 3-position switch that controls the application of 9 dB of treble boost or cut at  
10,000 Hz or flat response.  
6. AUX Input - High-impedance AUX RCA jack input.  
4
 
Connections  
70V & 25V Speaker Systems  
Connect the 25V or 70V speaker loads to the corresponding terminals (25V or 70V) and the common terminal.  
Make sure that the total wattage of all the connected speakers is less than 6 watts.  
Note: Do not use both the 25V and 70V terminals at the same time. Use only one type of speaker (25V or 70V) for all  
speakers connected to the GA6A.  
Note: If using multiple speakers, check for  
proper phasing. See Section on Phasing.  
Link  
The shorting link must be in place when using 25V or 70V speakers.  
8 Speaker Systems  
Low-impedance 8-ohm speakers can be connected to the GA6A.When using multiple speakers, the installer must  
make sure that the total speaker load is not less than 8 ohms. Higher impedances than 8 ohms are safe to connect  
to the GA6A, but the GA6A will not deliver its full output power to these higher impedance loads.  
Connect the 8-ohm speaker load to the GND and 8-ohm terminals and remove the shorting link. 25V and 70V  
outputs will not work in this configuration.  
Note: If using multiple speakers, check for  
proper phasing. See Section on Phasing.  
5
 
Connections  
Phasing  
As the voltage on a speaker changes from plus to minus, the  
speaker cone moves from pushing out to pulling in.If you reverse  
the polarity, the speaker responds in the opposite manner.  
If a speaker is pushing out and an adjacent speaker is pulling in,  
some of the pressure caused by the speaker pushing out will be  
absorbed by the speaker pulling in. These two speakers are  
operating out of phase.  
In a paging system, all the speakers should be in phase so that  
they all push out at the same time. Out of phase speakers  
operate perfectly well and will not cause any harm to a paging  
system, but will tend to diminish the bass response in the area  
around the out of phase speaker.  
The important thing is to wire all the same polarity (+ or -)  
connections together.This will ensure that the speakers in the  
system all work in unison.All paging speaker connections have a  
polarity indicator. It may be a color code, plus (+) and minus (-)  
symbols, or a red dot.  
+
+
+
+
Out-of-phase speaker connection.  
Microphone Input  
Connect a low-impedance dynamic microphone (these  
microphones connect using 3 wires and do not require a power  
source) to the microphone terminals as shown.  
Note: Condenser microphones will not work with the GA6A because  
the GA6A does not supply phantom power, which is required for these  
microphones to operate.  
Use two-conductor shielded cable for a balanced input and  
connect the shield to the ground terminal.  
Auxiliary Input  
Use a shielded RCA cable to connect to the high-impedance  
AUX input.The center of the connector is hot and the outside  
is ground.  
Power and Grounding  
The AC line cord should be plugged into a three-wire, grounded  
outlet providing 120V AC, 60 Hz. It is important to ground the  
unit. If a three-wire outlet is not available, use an adapter to con-  
vert a standard two-wire outlet for use with three-wire plugs.  
Connect the grounding pigtail on the adapter to the screw  
securing the wall plate. If the wall plate screw is not grounded, it  
will be necessary to connect a grounding wire from the GND  
terminal on the rear of the amplifier to a suitable ground.  
6
 
Operation  
Power  
The AC line cord should be plugged into a three-wire, grounded outlet  
providing 120V AC, 60 Hz.The power switch illuminates when unit is  
switched ON.  
MIC Control  
Controls the amount of MIC signal heard at the output. Clockwise  
increases the signal.  
AUX Control  
Controls the amount of AUX signal heard at the output. Clockwise  
increases the signal.  
Treble Control Switch  
Provides a stepped increase or decrease in high frequency (above  
10 kHz) heard at the output.The “Cut” position can help reduce high  
frequency feedback. The “Flat” position provides no modification to  
high frequency response. The “Boost” position provides more clairty  
and intelligibility to speech.  
Overload Protection  
The amplifier output is protected against overload and shorted speaker  
lines by a thermostat enclosed in the power transformer. If the breaker  
opens, the amplifier will have no output. Set the Power switch to OFF  
and wait a reasonable time for the breaker to reset. If the breaker trips  
again, have the trouble investigated by a qualified technician.  
7
 
Specifications  
Power Output:  
6 watts RMS  
Frequency Response:  
Total Harmonic Distortion:  
Inputs:  
30 Hz - 12 kHz +0 dB, -3 dB  
Less than 1% at rated output power  
Lo-Z MIC, balanced;AUX  
Sensitivity:  
MIC 0.3 mV;AUX 0.2V  
Hum & Noise:  
Output Impedance:  
Tone:  
MIC -50 dB;AUX -70 dB  
8 ohms, 25V and 70V speakers  
Treble boost at 10 kHz 9 dB, treble cut at 10 kHz 9 dB (switch selected)  
MIC,AUX, illuminated POWER switch, tone switch  
Outputs & microphone: screw terminals  
Auxiliary: RCA phono jack  
Controls:  
Terminations:  
Protection:  
Power Consumption:  
Dimensions:  
Power thermal protection  
120V AC, 60 Hz, 16W  
1
8- /2" W x 6" D x 2-5/8" H (21.6 x 15.2 x 6.7 cm)  
Shipping Weight:  
5 lb. (2.3 kg)  
Warranty  
The GA6A is warranted to be free from defects in material or workmanship for two (2) years from the date of sale to the original  
purchaser. Any part of the product covered by this warranty that, with normal installation and use, becomes defective will be  
repaired or replaced by Bogen, at our option, provided the product is shipped insured and prepaid to: Bogen Factory Service  
Department, 50 Spring Street, Ramsey, NJ 07446, USA. The product will be returned to you freight prepaid. This warranty does  
not extend to any of our products that have been subjected to abuse, misuse, improper storage, neglect, accident, improper  
installation or have been modified or repaired or altered in any manner whatsoever, or where the serial number or date code has  
been removed or defaced.  
THE FOREGOING LIMITED WARRANTY IS BOGEN’S SOLE AND EXCLUSIVE WARRANTY AND THE PURCHASER’S SOLE  
AND EXCLUSIVE REMEDY. BOGEN MAKES NO OTHER WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED,  
AND ALL IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE HEREBY DIS-  
CLAIMED AND EXCLUDED TO THE MAXIMUM EXTENT ALLOWABLE BY LAW. Bogen's liability arising out of the manufac-  
ture, sale or supplying of products or their use or disposition, whether based upon warranty, contract, tort or otherwise, shall be  
limited to the price of the product. In no event shall Bogen be liable for special, incidental or consequential damages (including,  
but not limited to, loss of profits, loss of data or loss of use damages) arising out of the manufacture, sale or supplying of products,  
even if Bogen has been advised of the possibility of such damages or losses. Some States do not allow the exclusion or limitation  
of incidental or consequential damages, so the above limitation or exclusion may not apply to you. This warranty gives you  
specific legal rights, and you may also have other rights which vary from State to State.  
Products that are out of warranty will also be repaired by the Bogen Factory Service Department -- same address as above or call  
201-934-8500. The parts and labor involved in these repairs are warranted for 90 days when repaired by the Bogen Factory  
Service Department. All shipping charges in addition to parts and labor charges will be at the owner's expense. All returns require  
a Return Authorization number.  
50 Spring Street, Ramsey, NJ 07446  
Tel: 201-934-8500 Fax: 201-934-9832  
 

Billion Electric Company Network Router 8501 User Manual
Cadco Food Warmer CMLB 24P User Manual
Canon Copier FY8 13EX 000 User Manual
Carrier Air Cleaner 120 60 1 User Manual
Cateye Heart Rate Monitor Heart Rate Computer User Manual
Chamberlain Garage Door Opener 2500BC User Manual
Chicago Electric Fan 67594 User Manual
Cisco Systems DVR 8389DVB User Manual
Cisco Systems IP Phone SPA921 User Manual
Cisco Systems Network Card Modular Gigabit Ethernet Line Card I User Manual