Linear Power 452i Programming manual

MODEL 452i©
(1989-MSRP $250.00)
F O R T H E L O V E O F M U S I C
™
OWNER'S MANUAL AND
INSTALLATION GUIDE
TECHNICAL DESCRIPTION
The amplifier design incorporates an unregulated power supply for increased
dynamic headroom efficiency. The output stages of the Linear Power™452i©
amplifier will deliver a significant increase in power into 2-ohm stereo loads.
Amplifier reliability is accomplished by the amplifier operation level being set at
approximately 50% of output transistors' rated power handling, even at this lower
impedance load. The 452i©incorporates inverting capabilities on the right
channel, which allows the amplifier to bridge without the use of and external
bridging device such as a pre-amp or crossover. This feature will also allow the
amplifier to play in the channel mode.
WIRING
Disconnect battery ground cable before making any power connections.
RED WIRE: +12 volts. Connect directly to battery positive terminal and should be
fused within 18 inches of battery and another fuse where the connection to the
amplifier is made. Remember to use the proper size fuses. WARNING: USING
OVERSIZED FUSES IS DANGEROUS AND WILL VOID THE WARRANTY!
See specifications for proper fuse size. Do not install power fuse until amplifier
installation is complete.
BLACK WIRE: negative ground. Connect to clean, unpainted metal surface on
car chassis.
RED/WHITE WIRE: Remote turn on lead requires 12 volts; connect to power
antenna lead from radio. When this not available, you may connect to a +12 volts
wire that is on with the ignition on or in the accessory position.
RCA CONNECTIONS: Connect with quality-shielded patch cords from source,
crossover, or any other sound processor.
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
1

SPEAKER CONNECTIONS: Screw wires onto connector block, with wires
attached as follows: (From Left to Right): first slot Left (-), second slot Left (+),
Third slot Right (-) and fourth slot Right (+) For mono operation use Left (+) and
Right (-). These amplifiers are capable of 2-ohm operation in stereo or 4 ohms
in mono.
OPERATING THE AMPLIFIER AT LESS THAN THESE RATINGS WILL
CAUSE AMPLIFIER FAILURE AND VOID YOUR WARRANTY.
NOTE: The 452i©have internal speaker protection fuses. If there is no output
from the amplifier, check these fuses, as your warranty does not cover their
replacement. Replace fuses only with fuses having the same rating. The
proper fuse is a GMA-5, 5-amp fuse per channel. Some later model amps may
use an ATC 5-amp fuse.
IMPROPER FUSING WILL DAMAGE YOUR AMPLIFIER!
2-Channel Stereo Operational Diagram
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
2

THREE CHANNEL:
STEREO PLUS SINGLE SUBWOOFER
To build a single amp system with two satellites and a subwoofer, configure the
amplifier outputs as follows: Using 4-ohm satellite speakers, hook them up for
normal stereo operation as described above. Then, using a 4-ohm subwoofer
speaker, hook it up using the two CENTER connections on the terminal strip.
Follow the polarity of the strip as described in the section above. A second set of
satellites may be added for 2-ohm operation.
3-Channel Operational Diagram
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
3

BRIDGED MONO OPERATION:
The Model 452i©is built with the right channel inverted. This allows the amplifier
to be used in a bridged mono configuration. Using an 8-ohm subwoofer speaker,
hook it up using the two CENTER connections on the terminal strip. Follow the
polarity of the strip as described in the section above.
This amplifier is capable of driving 4-ohm loads in the mono bridged mode. For
increased sound pressure levels, a 4-ohm load may be used. For systems
requiring higher sound quality, an 8-ohm load is recommended.
Bridged/Mono Operational Diagram
GAIN ADJUSTMENT
Set the amp gain to minimum, turn the source up until it just starts to distort, then
back down slightly. This is the point where the output of the source is cleanest.
Now adjust the amplifier gain up until it just starts to distort and back down
slightly. This will allow the source and amp to reach maximum usable output at
the same time.
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
4

MOUNTING
1. The amplifier will work best if it is kept as cool as possible. Mount in a position
that allows air to flow freely through the fins. Be sure there is ample space above
the amplifier to avoid trapping heated air rising from the amplifier. The amplifier
should not be mounted upside down. Avoid mounting any amplifier in the dash or
on the firewall to avoid noises being radiated directly into the case.
2. The case of your amplifier is designed to act as a noise shield. To maintain
this protection, be sure the metal case of the amp does not touch the metal of the
car. Do not remove or damage the rubber grommets, which provide electrical
insulation and vibration isolation.
GENERAL TROUBLESHOOTING
NO SOUND: Check all connections. Check main power fuse. Check accessory
fuse of your vehicle. Check to see that +12Vdc is present at the amplifier on the
power wire, and on the red/white remote turn-on wire. Check for a solid ground
connection. Check that the main music source is putting out signal.
BLOWS FUSES: Check all connections to be sure no wires are touching each
other or the chassis of the vehicle or any other equipment in your install. Check
that your speakers are in proper working order.
SHUTS OFF: These amplifiers are equipped with a Thermal Shutdown System.
If the amplifier becomes too hot during operation, it will shutdown until it cools to
proper operating temperature. This can be caused by lack of proper air
circulation to the amp, or too low of speaker impedance.
INTERNAL SPEAKER FUSES
The 452i©is equipped with internal speaker fuses to protect these amps and
your speakers. If you lose operation of one or both channels in these amps, first
check all the connections. If the internal fuses need replacement, remove the
faceplate of the amp and replace the fuse(s) with one of the correct size and
type. The 452i©uses a GMA-5, 5 AMP style fuse. Later model amps may use an
ATC-5 style, 5-amp fuse. Check all speaker wiring, or the speaker to insure
against shorts, also check for proper speaker impedance.
Remember, the fuse did not fail without reason!
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
5

SERVICE OR REPAIR
To obtain modification, service or repair, please contact our ONLY Authorized
LINEAR POWER™ Product Service Center:
T.I.P.S. INC.
3455 Lanell lane, Pearl, MS 39208
[phone]
E-mail: [email protected]
™
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© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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Specifications
452i©
Power output @ 4 ohms RMS @ 12.5 volts 22.5X2
THD @ full output 20-20KHz .01%
Slew Rate volts/microsecond 8Vms
Damping factor @ 4 ohms/2 ohms >100/50
Channel separation 60dB
Maximum current
4 ohms 8A
2 ohms 12A
Idle .7A
Fuse rating (12 Volt Power Feed) 12A
Dimensions 2x7.7x5.5
Internal Speaker Fuse ratings 5 A
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
7
™
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