Linear Power PA-2 AudioPath Enhancer User manual

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F O R T H E L O V E O F M U S I C
MODEL PA-2©
AUDIOPATH ENHANCHER©
(1998-MSRP $399.00)
OPERATION
INSTALLATION MANUAL
INTRODUCTION
After countless hours of analyzing the performance of existing car audio systems,
it became obvious to the engineers at LINEAR POWER™ that certain areas of
the audio spectrum consistently needed help. Something was needed to provide
optimum performance to the system whether you were listening while cruising
down the highway or sitting in traffic. A product you could use without having to
stare at tiny menus till your head exploded from trying to figure out whether you
were adjusting right rear time delay or the "Q" on the parametric EQ band
centered at 50Hz. An EQ that wouldn't blast you with screeching maximum
volume mids because you hit a bump in the road while you were trying to adjust
it. Enter the LINEAR POWER™ PA-2©. Your new preamplifier will dramatically
improve the dynamics, clarity, versatility and overall performance of any mobile
electronics audio system. Hey, and such a novel idea... YOU CAN USE IT
WITHOUT LOOKING AT IT. Enjoy the Music!!
PRODUCT OVERVIEW
The PA-2©is a combination line driver/4-band EQ preamplifier with internally
patched or externally patched fader capability. Two stereo inputs with electronic
source select are available for systems with two audio sources. Up to six audio
outputs are available at one time to provide in-dash control of multiple amplifiers
in your installation. There are separate input gain controls for the left and right
channels, a green power LED to indicate the preamplifier is powered up, and a
red clip LED to indicate 5Vrms output level. The PA-2©has a backlit display and
is housed in a rugged, half-din chassis with plug-in power connections.
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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CONFIGURING THE PA-2© IN YOUR SYSTEM
Your purchase of the LINEAR POWER™ PA-2©is a major step towards creating
the ultimate audiophile system for your vehicle. Before installing your new PA-2©,
the preamp must be properly configured for your system. The PA-2©
configuration is changed by moving 'shunts' inside the preamp chassis like those
used for computers. Remove the top cover of the preamp and locate the 'shunts'
near the RCA jacks and above the "LP" logo on the circuit board.
The PA-2©is shipped from the factory configured for two audio source input with
front/rear fader control patched internally. The sample system shown in Figure
1a allows front/rear fader control without affecting the main output level sent to
your subwoofer amplifier. The signal from the main output is sent to the fader
control in this configuration. See Figure 1B for the internal shunt settings.
For systems using an external crossover such as the LINEAR POWER™ X0-2©,
(Figure 2a), the PA-2©can be configured for externally patched fader capability
to prevent the subwoofer level from being affected by the front/rear fader control.
The signal from the second input on the PA-2©is sent to the fader control in this
configuration. See Figure 2b for the internal shunt settings.
For the maximum in-dash control and optimum sound quality in your system, the
PA-2©can be used with the LINEAR POWER™ X0-3©crossover. Patch the
signal from the main output on the PA-2©to the X0-3©crossover, (Figure 3a),
and use the three level controls on the X0-3©mounted in-dash to balance the
signal levels in your system. The fader circuitry is completely disconnected from
the audio path in this system to prevent any circuit loading from the unused fader
control that may affect sound quality. See Figure 3b for the internal shunt
settings.
Diagrams start on the following 3 pages.
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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CONTROLS AND INDICATORS ON YOUR PA-2©
VOLUME: The volume control sets the output level of the main output, front fader
output, and rear fader output on the PA-2©without affecting the input gain
settings.
FADER: The fader control balances the signal level between the front fader and
rear fader stereo outputs on the PA-2©without affecting the input gain settings.
The maximum output level on the front fader and rear fader outputs is set by the
volume control.
EQ CONTROLS; sub: 45Hz +/- 16dB
bass: 190Hz +/- 12dB
mid: 3.5kHz +/- 12dB
treble: 14kHz +/- 12Db
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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The EQ controls can affect the optimum input gain setting. See the section on
INPUT GAIN ADJUSTMENT in this manual in order to get the best performance
out of your PA-2©.
POWER INDICATOR:The red clip indicator will light at signal levels greater than
5Vrms even though the PA-2©does not actually clip until the signal level is
approximately 10Vrms. The 5Vrms signal level was chosen by our engineers in
order to provide your car audio system with excellent channel separation and
great power supply noise isolation while still providing a high output signal level
for driving the audiopath to your amplifiers. If the clip indicator is constantly
flashing or staying on steadily, readjust the input gain controls in the top cover of
the PA-2©as outlined in the INPUT GAIN ADJUSTMENT section of this manual.
The clip indicator should flash occasionally on musical peaks to obtain optimum
performance with LINEAR POWER™ amplifiers.
INSTALLATION OF THE PA-2© IN YOUR SYSTEM
POWER CONNECTION: Connect the red wire labeled bat on the top cover to
one end of a 500mA AGC style fuse. Connect the other end of the 500mA AGC
style fuse to the exact same location that the head unit receives its constant
power.
GROUND CONNECTION: Connect the black wire labeled gnd on the top cover
to the exact same location the head unit is connected to ground.
REMOTE TURN-ON CONNECTION: Connect the blue wire with the white stripe
labeled rem on the top cover to the power antenna or remote turn-on output on
the head unit whose signal is connected to the source 1 input. This input wire
turns on the PA-2©. It is not an output wire as in previous versions of the PA-2©.
SOURCE SELECT CONNECTION: If you are using two head units (e.g. cassette
and CD) in your system, connect the white wire labeled src2 to the power
antenna or remote turn-on output of the head unit whose signal is connected to
the source 2/fader input. When the head unit connected to the source 2/fader
input is turned on the source 2/fader input on the PA-2©will automatically be
selected. When the head unit connected to the source 2/fader is turned off, the
source 1 input on the PA-2©will automatically be selected. Alternatively, the src2
wire can be connected to an external switch. When this switch supplies +12Vdc
to the src2 wire, the source 2/fader input on the PA-2©will be selected. When
this switch supplies 0Vdc to the src2 wire, the source 1 input will be selected.
INPUTS/OUTPUTS: The RCA (phono) jacks will accommodate signal levels from
100mV RMS to 10V rms. To minimize system noise, avoid routing signal cables
near power wires, power connections, speaker wires, engine alternator, or fire
wall of the vehicle.
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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INPUT GAIN ADJUSTMENT:
1. Rotate the left and right input gains located in the top cover of the PA-2©fully
counterclockwise.
2. Set all EQ controls on the source and on the PA-2©to the neutral position
(i.e.- no boost or cut).
3. Choose a tape or CD with a high signal level and increase the volume control
on the source to the maximum level where you still have clean output. The
volume control on the PA-2©should be in the position that gives you a
comfortable listening level while doing this step. After completing this step, never
touch the volume, fader, or EQ controls on the head unit again. Use only the
volume, fader, and EQ controls on the PA-2©.
4. Rotate the volume control on the PA-2©fully counterclockwise. While playing
the same music from step 3, rotate the L input gain control slowly clockwise until
the clip indicator just begins to flash. Now, rotate the L input gain control
counterclockwise until the clip indicator just stops flashing. Repeat this process
for the R input gain control. The PA-2©is now providing a 5Vrms output level to
send to the next component in your audiopath.
5. Adjusting the EQ controls on your PA-2©can affect the maximum output
signal level of the preamplifier. After setting the EQ controls where you want
them, check the clip indicator to be sure it is flashing occasionally on musical
peaks. When checking the clip indicator, the position of the volume and fader
controls does not matter. If the clip indicator never flashes, flashes constantly, or
stays on all of the time, leave the EQ controls where you have set them and
repeat steps 1 and 4. The clip indicator should flash occasionally on musical
peaks to obtain the optimum performance with LINEAR POWER™ Amplifiers.
GENERAL TROUBLESHOOTING
NO SOUND: Check all signal connections. Check that the power indicator is on.
Check for the +12Vdc on the bat and rem wires. Check the gnd wire connection.
Bypass the PA-2©and check for signal output.
BLOWS FUSES: Check all connections to be sure all power wires do not touch
ground or each other. Re-check polarity of main power wires.
NOISE PROBLEMS: Be sure the metal sleeve on the RCA (phono) jack does
not touch the metal chassis of the vehicle, the chassis of the PA-2©, or the
chassis of any other component in your installation. Route signal cables away
from power wires, power connectors, speaker wires, engine alternator and
vehicle firewall. Make sure all amplifier(s) or head unit(s) are properly and
securely grounded.
© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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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
PA-2©AUDIOPATH ENHANCER
THD + Noise .002%
Frequency Response 3Hz - 75kHz
Signal-to-Noise (min / max gain) 102dB / 100dB
Channel Separation >80dB
Input Gain 0 - 30dB
Input/Output Impedance 47K Ohms/ 75 Ohms
Recommended Fuse (+12Vdc, red wire) 500mA AGC
Faceplate Dimensions 1.00"x7.00"x0.06"
Dimensions 0.95"x6.65"x5.00"
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© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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© 2008 Linear Power, Inc. - ALL RIGHTS RESERVED
LINEAR POWER™ is a trademark of Linear Power, Inc.
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