Clarity SMA-40 User manual

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CSP SMA-40/60/120
Issue 4
[phone]
SMA-40, SMA-60, SMA-120
40, 60, AND 120 WATT MIXER-AMPLIFIERS
INTRODUCTION
These instructions contain the specifications and
information necessary to install, operate, and maintain
the SMA-40, 40 Watt Mixer-Amplifier, the SMA-60,
60 Watt Mixer-Amplifier and the SMA-120, 120 Watt
Mixer-Amplifier manufactured by Clarity, 1111
Industry Avenue., Roanoke, VA 24013.
"WARNING: To reduce the risk of fire or electric
shock, do not expose this appliance to rain or
moisture."
"WARNING: Shock Hazard - Do Not Open."
"AVIS: Risque de Choc Electrique ne pas Ouvrir."
SPECIFICATIONS
Purpose
The SMA-40 Mixer-Amplifier provides up to 40 watts
of audio power, the SMA-60 provides 60 watts, and the
SMA-120 provides up to 120 watts of audio power for
voice paging or background music systems.
Applications
•Clarity Paging and Sound Reinforcement Systems
•Clarity Stand Alone Background Music Systems
Refer to Figure 1 for a block diagram of a typical
installation.
Features
•Active mix or Priority override on inputs (override
is voice operated)
•Shelf or rack mount (optional kit)
•Mic 1/Tel on Input 1, 3 standard MIC/AUX
inputs
•Volume control for each input
•Master volume control
•Bass control
•Treble control
•Circuit breaker protection
•ON/OFF switch
•Overload limiting circuit protection
•Screw terminals for all connections
•Power "ON" indicator
•2 ohm, 25 and 70 volt outputs on the SMA-120
•4 ohm, 25 to 70 volt outputs on the SMA-40 and
SMA-60
•Knobs for all controls
•Clipping indicator
•Effects loop
•Tape output
•Booster output
Dimensions and Weight
•17.1"W x 12.5"D x 3.9"H
(43.43cm W x 31.75cm D x 9.9cm H)
•24 lbs. (10.8 Kg) - SMA-120
•20 lbs. (9.1 Kg.) – SMA-40 and SMA-60
Power Requirements
Voltage 120 VAC
Current (SMA-40) 1.0 Amps
(SMA-60) 1.6 Amps
(SMA-120) 3.0 Amps
Environment
Temperature 0 to 50 Degrees C
Humidity 0 to 85% non-precipitating
947408

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Nominal Specifications
Wattage Output (SMA-40) 40 Watts RMS
Type Outputs (SMA-40) 4 ohm or 25V or 70V
Wattage Output (SMA-60) 60 Watts RMS
Type Outputs (SMA-60) 4 ohm or 25V or 70V
Wattage Output (SMA-120) 120 Watts RMS
Type Outputs (SMA-120) 2 ohm or 25V or 70V
For All Models:
Frequency Response 30-20KHz +2dB
Distortion < 2% @ 1KHz Rated Output
Number of Inputs 4 (1 Mic/Tel Line,
3 Mic/Aux)
Mounting Wall or Rack
Voice Switch Sensitivity -31dbm
Mic Input Impedance 600 ohm Balanced
Sensitivity on Mic Input 1.0mV RMS
Tel Line Input Impedance 600 ohms
Tel Line Sensitivity 200mV RMS
Aux Impedance 10K ohms
Aux Sensitivity 200mV RMS
Effects Out 1V RMS +20%
Effects In 1V RMS 10K
Tape Out 1V RMS 10K
Booster Out 2.6V 10 K Loading
Loading Level 10K High
DESIGN
The SMA-40 and SMA-60 amplifiers can be used to
operate 4 ohm, 25 or 70.7 volt type speakers and horns
and the SMA-120 amplifier can be used to operate 2
ohm, 25 or 70.7 volt type speakers and horns. These
mixer-amplifiers will actively mix all inputs or will
provide priority inputs. If priority input is selected, the
Mic/Tel input will override all inputs that are active.
(Refer to Table 1 in the Operation Section for the
override sequence). When the amplifier is in the
priority mode, the switching is voice operated. (No
contacts are required).
These amplifiers have a master volume control plus a
separate volume control for each input. Bass and treble
controls are also provided.
A circuit breaker is provided on the back of these units
and will operate in the event of a catastrophic overload.
The mixer-amplifier contains a limiting circuit for
protection against short circuits or impedance
mismatches. The units will shut down in the event of a
trouble condition and reactivate automatically when the
condition is corrected.
The amplifiers can be either shelf or rack mounted
(rack mount kit is optional).
INSTALLATION
General
Figure 2 shows volume control locations. Figure 3
shows output terminal strips and switches on the back
of the amplifier as well as typical connections to the
mixer-amplifier.

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NOTE: If the effects loop is not used, the slide switch
should be in the OFF position.
Mounting
The SMA-40, 60 and 120 were designed for shelf or
rack mounting. Make certain the unit is not mounted
near heat sources or strong magnetic fields. Verify
control and terminal strip accessibility. The unit may
be rack mounted. Order the associated rack mount kit
SMA-RMK.
MIC Connections
These units provide connections for low impedance
balanced microphones. Connect the positive pressure
lead of the microphone (normally pin 2 of a standard
XLR connector) to MIC (+) terminal connection,
microphone shield to MIC COM terminal and the
negative pressure lead of the microphone to the
remaining MIC terminal connection as shown in Figure
3.
Telephone System 600 Ohm Page
Port Connection
When using these mixer-amplifiers with a 600 ohm
telephone system page port, connect page port Tip to
the TEL (+) terminal and connect page port Ring to
TEL-COM as shown in Figure 4.
NOTE: Interface devices are required when
connecting to outside C.O. Lines, PABX extensions,
or single line telephones.
Auxiliary Connections
High impedance auxiliary devices such as a tuner, tone
generator, etc. can be connected to the AUX input.
Phono jacks are provided at the rear of the amplifier for
each of the auxiliary inputs.
Speaker Cabling
When the 2 or 4 ohm output is used, standard two
conductor speaker wire can be used (18-20 AWG
determined by the load). If the 25 or 70V output is
used, two conductor shielded cable is recommended for
speaker connections. NOTE: When shielded cable is
used, the shield should be connected to the Ground
terminal located on the back of the amplifier.
Priority Override
To enable the cascading priority override feature,
install a wire strap on the two terminals marked priority
on the back of the amplifier (see Figure 3).
Amplifier Setup
During initial system set up, it is recommended that the
individual gain controls be set 1/4 turn clockwise
and the master volume control be set 1/2 turn
clockwise.
All connections should be made to the amplifier and
double-checked before the AC power cord is plugged
in. The power indicator will illuminate when the AC
power cord is plugged in and the power switch is in the
"ON" position.
OPERATION
These units provide two modes of operation, either
active mix or priority override.
When the amplifier is in the active mix mode signals on
all inputs are mixed and sent to the speakers. When the
priority input is selected, a signal on the MIC/TEL
input will override all other active inputs (See Table 1
for override sequence). The override is voice activated
and does not require the use of an external relay or
contact closure. The separate gain controls on the unit
allow adjustment of the volume levels of each input.
A clipping light is provided on the front of the unit.
This light will illuminate when the output signal
exceeds the power rating of the amplifier.
Table 1 - Override Sequence
Input Priority Level
Mic 1/TEL
Mic 2/Aux 1
Mic 3/Aux 2
Mic 4 /Aux 3
1
2
3
4
NOTE: Level 1 is highest priority.
TECHNICAL ASSISTANCE
When trouble is reported, verify that AC power is
being supplied to the unit and there are no shorts or
grounds on cabling.
Assistance in troubleshooting is available from the
factory. When calling, you should have a VOM
available and be calling from the job site. Call (540)
427-3505 and ask for Technical Support or (540) 427-
6000 for Clarity 24-hour Automated Support.

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Clarity equipment is not field repairable. Clarity
maintains service facilities in Roanoke, VA. Should
repairs be necessary, attach a tag to the unit clearly
stating company name, address, phone number, contact
person, and the nature of the problem. Send the unit to:
Clarity
Repair and Return Dept.
5614 Hollins Road
Roanoke, VA 24019-5056
TROUBLESHOOTING CHART
PROBLEM POSSIBLE SOLUTION
No Output. 1. Verity AC power is being supplied to the unit and the power switch is in the
"ON" position.
2. Verity that input signal is present at amplifier connection.
3. If speaker controller or equalizer is not being used, make sure that effects switch
is in the "OFF" position.
4. Verity all speaker wiring (no opens, shorts, or grounds).
Distorted output. 1. Check input wiring for proper polarity connections.
2. Verify that speaker load does not exceed amplifier rating.
3. Verify input signal does not exceed input voltage rating.
4. Verify all speaker wiring (no opens, shorts, or grounds).
Override does not operate. 1. Verify priority strap is installed.
2. Verify input signal is at proper level.
LIMITED WARRANTY
Clarity warrants its products to be free from defects in materials and workmanship under conditions of normal use and service for a
period of one year from the date of shipment. The obligation under this warranty shall be limited to the replacement, repair or refund of
any such defective device within the warranty period, provided that:
1. Inspection by Clarity indicates the validity of the claim;
2. The defect is not the result of damage, misuse, or negligence after the original shipment;
3. The product has not been in any way repaired by others and that factory sealed units are unopened (A service charge plus parts
and labor will be applied to units defaced or physically damaged);
4. Freight charges for the return of products to Clarity are prepaid,
5. All units “out of warranty” are subject to a service charge. The service charge will cover minor repairs (Major repairs will be subject
to additional charges for parts and labor).
This warranty is in lieu of and excludes all other warranties, expressed or implied, and in no event shall Clarity be liable for
any anticipated profits, consequential damages, loss of time or other losses incurred by the buyer in connection with the
purchase, operation, or use of the product.
This warranty specifically excludes damage incurred in shipment. In the event a product is received in damaged condition, the carrier
should be notified immediately. Claims for such damage should be filed with the carrier involved in accordance with the F.O.B. point.

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