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Alpine KTP-445U Power Pack

180W RMS Power Pack Series Compact Class D 4-Channel Car Amplifier

Alpine
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• RMS Power: 45W x 4-Chan. @ 4 Ohm
• Adjustable Gain Switch
• Plug-and-Play
• CEA-2006 Compliant

Learn more about the ktp445u

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This item has been discontinued


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Product Highlights


• RMS Power: 45W x 4-Chan. @ 4 Ohm
• Adjustable Gain Switch
• Plug-and-Play
• CEA-2006 Compliant

Description


Alpine brand icon

Authorized dealer

General Features:

  • Alpine Universal Power Pack 4-Channel Class D for All In-Dash Receivers
  • The fast and easy solution to higher power aftermarket sound
  • RMS Power Rating:
    • 4 ohm: 45 watts x 4 chan.
    • 2 ohm: 45 watts x 4 chan.
    • 4 ohm: 90 watts x 2 chan. (Bridged)
  • Total RMS power output: 180 watts
  • CEA-2006 compliant amplifier
  • Increases the output of any headunit without having to install a full size amplifier and amp install kit
  • Independent Front/Rear gain switch is adjustable from high to low
  • Runs off receiver's power circuit
  • High-Pass Filter: selectable 60/80/120 Hz @ 12 dB/octave
  • Fast and simple installation
  • 4 channel operation for four speakers
  • Minimum impedance of 2 ohm
  • Is not compatible with factory amplifiers
  • Frequency response: 20-20,000 Hz
  • Fuse Rating: 15A x 1
  • Dimensions: 7-13/16D x 2-9/16"W x 1-1/2"H
  • Authorized Internet Dealer
  • 1-year Sonic Electronix Warranty

PDF IconAlpine KTP445U owner’s manual

Product history:

Alpine KTP-445U thumbnail
(newest, current model)
Alpine KTP-445 thumbnail
(previous model, replaced by Alpine KTP-445U Power Pack)

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Specifications & Details


Key Features
Amplifier Key Features
Compact Design
Speaker Level Inputs
Power Specifications - Full Range Channels
RMS Power @ 4 ohms
45 watts x 4 channel
RMS Power @ 2 ohms
45 watts x 4 channel
Bridged RMS Power
90 watts x 2 channel
Amplifier Specifications
Series
Power Pack Series
Amplifier Class
D
Number of Channels
4-Channel
Total RMS Power Output
180 watts
Maximum Input Gauge Size
8 AWG
Minimum Impedance Unbridged
2 ohm
Minimum Impedance Bridged
4 ohms
Frequency Response
15 - 45000 Hz
THD at Rated RMS Power
1%
Speaker Level Inputs
Yes
Preamp Outputs
No
Built-in Crossover
High-Pass (HP)
High-Pass Crossover Frequency
60 - 120 Hz
Signal-to-Noise Ratio
82 dB
Remote bass/level controller
No
Fuse Rating
15A x 1 
Total Fuse Rating
15
Strappable
No
Amp Bluetooth Connectivity
No
Hi-Res Certified
No
Low-Level Input Sensitivity
0.2 - 4 volts
High-Level Input Sensitivity
0.5 - 10 volts
What is in the box?
Paperwork
User manual
Warranty/Registration card
WITB: Amplifiers
Amplifier
Mounting screws (4)
High-level input wiring harness w/ molex connector
Warranty and Return Policy
Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider
Sonic Electronix

Item Details


Manufacturer:

Model Number:

KTP-445U

Weight:

2.40lbs

Internal SKU:

ktp445u

Internal Product ID:

60631

Product and How-to Videos


Customer Ratings & Reviews


Alpine KTP-445U Power Pack thumbnail image

5 star
92%
4 star
8%
3 star
0%
2 star
0%
1 star
0%



Durability
4.8
Value
5
Features
4.6
Design
4.9
Usability
4.9

Customer Reviews

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Great Product for entry level setup!

After building several full all out setups on my previous vehicles, I wanted to try a more simple build for my current car since I don't want to spend too much time running new wire, mounting amps, etc. and I do not have the luxury of putting a sub since I need the cargo space for work.

I was hesitant getting this amp since I thought it would only give a little more than an aftermarket headunit and heat up, but I really liked the size of it (tucked behind the glovebox) and how simple it is to wire it up. I installed it today with a pioneer headunit, JL TR components in front, JL TR coax in rear, all doors deadened, gave it a good tune by ear and to my surprise it sounds great! Well 50x better than my base unit and stock speakers.

The sound is nice and clear, has a good thump, no noise or muddy sound and I can hear all the sounds I was looking for (just over 1/2 gain) that my stock stuff could not even come close to producing. I definitely recommend this amp to anyone who is looking to do a simple upgrade on their system without the hassle of running new wire and looking for a place to mount or hide a traditional sized amp!

By Michael on January 6, 2014

72 found this helpful


powerpack

decent enough for small speakers for someone just starting out and doesnt wish to upgrade battery or alternator or run amp kits, however you get what you pay for and because its not an actual 4 chan or 6 chan amp dont expect the same sound quality or power coming from this little fella. value wise its pretty good and easy to install. might cause engine whine if you have to use a in line converter or data module for your specific vehicle.

By piyush on May 9, 2014

73 found this helpful


Nice little amp

This amp is perfect for small places, or to hide easily where not seen. Produces big sound in a small package and a great value. I love it.

By Chad on August 11, 2013

69 found this helpful


An absolute BEAST in a tiny package!

This thing cranks out some serious juice from such a small box. It's about the size of a red brick. It can be stashed up in the dash so you never even see it. And it makes WORLDS of difference.

It can accept low-level (RCA) inputs or high-level (speaker wire) inputs. (Just cut off the RCA tips, per instructions) It also has adjustable high pass filters for front and rear. (via DIP switches) Adjustable gain for front and rear. (via knobs)

This thing ROCKS. Unless you're planning on getting huge 4-channel amp that does at least 100WRMSx4@4ohm, then just get this. It's just as good as anything below that power range, despite what the figures on this may lead you to believe. I honestly think the power output is underrated. You WON'T be disappointed.

By Kenneth on January 19, 2014

66 found this helpful


Awesome

Does exactly as it says. Look elsewhere online for better reviews, but basically works amazing. Fits in center console of 05+ Tacomas.

By Wandulonian on January 27, 2013

63 found this helpful


Alpine KTP-445U

At first I didn't think this amp would sound that different than my stereo, but the extra 45 watts really brought my speakers alive. There is more bass, and the sound is so crisp and clear. Plus it fits in my glovebox and doesn't require an amp instillation kit. It's seriously perfect for anyone not wanting to deal with installing an amp kit. You wouldn't think this would do much to your speakers but you just have to try it. It is awesome!

By Smuck on January 9, 2014

64 found this helpful


not bad at all, great for factory speakers and entry level after-markets

would have bought from sonic, but were out of stock. bought from bestbuy instead. installation was surprisingly simple. wired into a single din pioneer with 3 rca level outputs (front, rear, sub - used front and rear obviously) with two 3 ft rca cables from radio shack. wired output into Scosche TA02B / TA02 and connected that to factory harness (speaker level, ground wire, batt, and remotes). worked flawlessly, made factory speakers sound phenomenal...almost to the point where i second guessed my purchase of new JL C2 sets...but added the JL's anyway and, big surprise, they sound great as well. instructions are a little convoluted but its fairly simple to install and use once you start. only problem now is finding a spot to mount it (its jus sitting in the glovebox). and yeah, the wires are short...not a huge issue if you purchase longer cables to go with it. very happy with it tho, would definitely recommend.

By J. Escuela on September 20, 2013

61 found this helpful


Amazing AMP!

this little amp is outstanding! way better than my 4 channel that was a size of a desktop! I bought a 2013 sonata gls all stock and the oem system sounded horrible so i decided to shop around for a small amp to tuck away behind the dash. I ran the power and gnd right off the stock decks power and I used the speaker level inputs which tied into the oem harness. i had to butcher due to the lack of aftermarket adapters. i guess no one likes hyundai! I had it for 6 months so far and i abuse this AMP. the gains are half way and it's pretty loud to the point where my ear drums starts to ring. this has filters 60/80/120 and off. For best overall sound highs crisps mids and deep low bass i had to turn the filters off. My music is reggae soca hip pop and house. My front speakers are Renegade RX62 6.5-Inch 2-Way Full Range Speakers and the rear are Kickers DS60 6.5 speakers. Do me a favor dont waste your money on a 300 dollar amp that fits under your seat which requires 4 gauage wire and all that crazy stuff it's not worth it. After all are you going to park your car inside a club and dj there?

By derek on May 15, 2014

63 found this helpful


wow!

Bought this amp because my factory radio was lacking power, hooked this bad boy up and the music came alive. Sounds outstanding!

By walter on March 9, 2014

62 found this helpful


Great if you Don't want wiring all over the car.

Really great product, i have a sets of Polks components 6,5" DB series in the front and DB 6,5" coaxial in the back, this little thing makes the job done, the speakers sound really loud without any distortion if you EQ well.

The price is fair and the Shipping To Chile really fast, i installed in a Suzuki SSwift Sport 2013, and with a limited space behind the dash, have to put it far from the source, so the wiring was not long enough, had to put new wire... i recommend to install it in a professional place, it seems easy to install but, removing some parts of the dash and trying to drill a base for the amp, that was the challenge.

The sound is good, very good for a Class D amp, so Don't expect audiophile sound. My source is a Panasonic OEM radio , not aftermarket, so i have to move the gain to have a louder sound, but try to do this with care, it's too sensitive and if you gone wrong with the right gain, it will distort at some points... and not, the speakers are 110 RMS and 50 RMS, so the distortion is not from them.

I recommend this amp if you don't want to go big, and don't want to wiring the entire car to put a amplifier in the back and then wiring again to the doors.

Soon i'm going to put a subwoofer, so the frequency selector to cut at 50-80 Hz it's a really great tool.

Good deal here.

By Kris on May 12, 2013

61 found this helpful




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