Overview: The Alpine KTP-445U Head Unit Power Pack is a power upgrade amplifier that allows you to add higher output and
more dynamic response to your aftermarket or factory installed car stereo system
(without factory amplifiers).
The KTP-445U amplifies your aftermarket or factory head unit's power output,
resulting in increased power over the original head
unit's built-in amplifier. It's small and compact at only 7.875" (w) x 1.5"
(h) x 2.5625" (d) and fits behind the head unit in the dash of most vehicles.
The KTP-445U comes equipped with RCA and auto-sensing speaker level inputs.
- Because of its high-powered amplifier design, the Alpine KTP-445A
does require that a separate +12V constant power wire is run to the
battery with a separate inline 15A fuse in vehicles with lower than a
15A fuse protecting the factory radio. Check out the "Accessories" tab
for wiring kit.
- This Alpine high-powered amp won't work in systems where an outboard
factory amplifier is still active. If used in vehicles with a factory
amplifier, the factory amp will need to be completely bypassed (this may
result in lost speaker channels, if factory amp has more than 4
- The increase in power may result in a louder warning chime in
45 Watt x 4 Channel Amplifier: The Alpine KTP-445U Head Unit
Power Pack employs a 45 watt x 4 channel amplifier. The amplifier offers an
unbelievably low noise floor, taking extra care to ensure a clean signal path,
with no extraneous interference. The end result is a 1 Watt Signal-to-Noise
Ratio of 82dB or better. Uniquely, the amplifier distortion actually decreases
at higher frequencies, resulting in a clean and clear signal where your ear is
most sensitive to distortion (< 0.03% THD+N @ 1W; 1% THD+N @ rated power).
CEA-2006 Compliant: The specifications given by Alpine for
the built-in amplifier comply with the CEA-2006 mobile amplifier power testing
and measurement standards from the CEA (Consumer Electronics Association). All
manufacturers who comply with the standard can display the CEA-2006 logo on
- CEA-2006 Power Rating: 45 watts x 4
channels (at 4/2-ohms, 20-20kHz, 1% THD)
- Bridged: 90 watts x 2 channels (4-ohm
- Max Power Output: 90 watts x 4 channels
Controls: The Alpine KTP-445U Head Unit Power Pack provides
independent controls for the Front & Rear inputs.
- Front & Rear Gains: The Power Pack
provides simple variable gain controls (speaker level: 0.5-10V,
low-level: 0.2-4V) for flexibility and a wide variety of system
- Front & Rear HPF: High-Pass selectable
switches for the amplifier's Front & Rear inputs allow
frequency filtering for a wide variety of speakers. Choose
"Full-Range" or a selectable range (60Hz, 80Hz,
120Hz) to fine-tune your crossover points (-12dB/oct.).
- Configurable Inputs: On the bottom panel
of the Power Pack there are selectable input options to accommodate
Speaker-Level (0.5V-10V) or RCA (0.2V-4V) inputs.
- 4Ch/2Ch Modes: Selectable 2-Channel &
4-Channel options give you the control to determine source inputs,
and can eliminate the need for Y-adapters.
Low-Level & Speaker Level Inputs: The Alpine KTP-445U Head
Unit Power Pack includes a 5.5" low-level/speaker-level input harness. The
harness features a proprietary 10-pin connector on one end that plugs into the
KTP-445U and two pair of stereo RCA inputs that connect to your source unit's
front & rear RCA outputs using a pair of stereo RCA cables (sold separately). If your source unit is not equipped with RCA outputs
and only features speaker-level outputs, then you can cut off the included
low-level/speaker-level input harness' RCA connectors (or use the optional
Speaker Wire to RCA Adapters) and connect the KTP-445U
to your source unit's front & rear speaker outputs.
Note: You will need to connect the
amplifier's remote turn-on lead wire (blue/white) to your
source unit's remote turn-on lead when connecting the
KTP-445U via Low-level (RCA). You do not need to connect
the remote turn-on lead wire when connecting the amplifier
via speaker-level input, because the speaker-level inputs
Power/Speaker Output Harness: The Alpine KTP-445U's
power/speaker output harness consists of a 16-pin proprietary connector on one
end that plugs into the KTP-445U, and bare wires on the other end to connect to
power/ground and your car stereo speakers through your vehicle's factory or
aftermarket head unit's wiring harness.
Note: The factory radio circuit needs to be a minimum of
15A. If it is not, a separate power and ground will need to be installed for
Mounting: The Alpine KTP-445U Head Unit Power Pack includes
cable ties to attach the amplifier to your vehicle's frame or chassis. The
KTP-445U also includes two mounting brackets and four hex-head screws to fasten
the amplifier to a flat surface of your vehicle.
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