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Alpine KTP-445

Plug and Play Head Unit Power Pack for Use with all 2005-Up Alpine Head Units (Black Harness)

Discontinued
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This item has been discontinued

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Alpine KTP-445U

OUR PRICE: $149.95

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  • Alpine Power Pack 4-Channel Class D for Select In-Dash Receivers
  • Increases the output of an Alpine headunit without having to install a full size amplifier and amp install kit
  • The fast and easy solution to higher power aftermarket sound
  • RMS Power Rating:
    • 4 ohms: 45 watts x 4 chan.
  • Total RMS power output: 180 watts
  • Gain switch is adjustable from high to low
  • Plug-and-play design for compatible Alpine headunits
  • Plugs directly into the wiring harness of the Alpine receiver
  • Fast and simple installation
  • 4 channel operation for four speakers
  • Minimum impedance of 4 ohms
  • Is not compatible with factory amplifiers
  • CEA-2006 compliant amplifier
  • 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
  • 1-year SonicElectronix.com warranty

Alpine products are warranted solely by Sonic Electronix, Inc. under the same period and terms as the original Alpine warranty. Sonic Electronix is not an Authorized Alpine Dealer and Alpine requires all merchandise purchased by Sonic Electronix customers to be returned solely to Sonic Electronix. Alpine products are also covered by our Standard Return Policy for returns on exchanges or refunds within 30 days from the date of purchase.

Product History:

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

Power Specifications - Full Range Channels

RMS Power @ 4 ohms

The RMS power rating is the measure of continuous power that an amplifier can output, or a speaker can handle. It is the most accurate depiction of real, continuous power that the industry has so far.

If the final impedance of your speakers or subwoofers equals 4 ohms, this is how much power this amplifier will supply at that ohm level. The higher the RMS wattage, the more clean and loud your music will sound.

45 watts x 4 channels

Amplifier Specifications

Amplifier Series
This designates the series of the amplifier. Many amps are available in a litany of different wattage and channel configurations, but maintain consistent features throughout the product line.
Amplifier Class

An amplifier increases the power of the signal being fed to it by taking energy from its power supply and matching the signal but increasing its amplitude. Amplifiers use many different methods for converting these electrical signals and have been categorized into classes.

Class A/B: Greater than 50% of the input signal is amplified while the other percentage is “off”. These amplifiers have a small amount of current flowing through the output transistors all the time which almost eliminates crossover distortion. Class A/B has great sound quality but is not as efficient as class D. These amps are most commonly used to drive speakers.

Class D: Also known as switching amplifiers, class D amps have output transistors that are completely turned “on” or “off”. This means that when the transistors are on, there is almost no voltage across them but when they are off there is significant voltage but no current flowing through it which makes these amplifiers very efficient at the cost of sound quality. These amps are most commonly used to drive subwoofers.

Other Classes: You may see classes such as GH, bD, X, FD, etc. by some manufactures. These amplifiers tend to be either class A/B, D or a hybrid of the two but with improvements to their designs that can make them more efficient or offer better sound quality.

D
Number of Channels
Each channel on an amplifier will power one speaker using a positive and negative cable. There are various types of amplifiers, each designed to power a certain number of speakers. Monoblock amplifiers, also known as single channel, are designed to power one or more subwoofers. These amplifiers often have very high power ratings. On the other hand, multi-channel amplifiers power multiple speakers, usually at lower power ratings. 2-Channel and 4-Channel amplifiers can power car speakers or low powered subwoofers. Occasionally you might see a 5 or 6-channel amplifier that can power speakers and subwoofers at the same time. The most common setup is a monoblock amp to run subwoofers and a 4-channel amp to run door speakers. Check out our Knowledge Base for more information.
4
Total RMS Power Output
Total RMS power is measured by multiplying RMS power per channel by the number of channels, and is calculated at the lowest level of operating impedance.

RMS power is the amount of continuous power, measured in watts, that an amplifier produces is called RMS power. The higher the RMS figure, the louder and cleaner your music sounds.

The RMS output figure is much more accurate than the peak rating when comparing products.

180 watts
Maximum Input Gauge Size
This is the largest gauge wire that will fit into the power and ground terminals of this device. The lower the gauge number, the thicker the wire is. For example, a 4 gauge wire is thicker than an 8 gauge wire and thus has higher current carrying capacity. Always do your best to get this size wire to reduce the risk of damage to your components.
Wire Harness
THD at Rated RMS Power
The amount of change in harmonic content of the signal as it is amplified. A lower figure indicates less change and a more accurate amp. THD below 0.10% is inaudible.
1%
Speaker Level Inputs
Speaker level inputs are commonly referred to as high-level inputs and vice versa. This input type allows you to get your audio signal directly from the speaker wire in your vehicle, instead of using RCA cables. The advantage of this is factory integration, as most stock radios do not have RCA outputs to run amplifiers.
Yes
Preamp Outputs
Many amplifiers are equipped with RCA preamp outputs which pass the original music signal from the source to additional amplifiers. This is known as daisy chaining because the source connects to the first amp, and the first amp connects to the second amp, etc. The advantage to daisy chaining is you only need one 2-channel RCA cable to transfer the signal from the head-unit to the amplifier, and then one additional cable for each amp being daisy chained.
No
Built-in Crossover

A crossover is a type of filtering system that permits only certain frequencies to play. A Low-Pass (LP) crossover allows only frequencies below its setting to get through which is good in the case of some subwoofers. A High-Pass(HP) filter allows frequencies above its setting to pass through, this is normally used on speakers.

When a crossover is set to FULL it means no filtering is added and the full frequency spectrum is allowed through the amplifier. Filtering is important because feeding a speaker frequencies it cannot reproduce effectively creates distortion.

None
Bass/Gain Remote
If the amp comes with a bass/gain remote you will be able to control the level of your bass from your dashboard. Typically bass remotes also include a 16-20 ft. wire for installation.
No
Fan Cooled
A great feature to have if an amp generates a large amount of heat. Cooling fans can help regulate the temperature to prevent the amp from overheating (burning).
No
Fuse Rating
The amperage and the number of fuse(s) an amp requires.
15A x 1 
CEA-2006 Compliant
Amplifiers that have been tested to meet specific standards. When a car amplifier meets these standards, you can be sure that it will be able to produce the amount of power specified by the official CEA-2006 rating. Usually, these rating consist of the following items:
  • RMS Power
  • Signal-to-Noise Ratio

This rating applies to both external car amplifiers, as well as the amplifiers inside of in-dash stereos.

Yes
Strappable
Some amplifiers can be "strapped" together in order to increase the output of a single audio channel. These amplifiers feature RCA preamp outputs, allowing you to pass the signal directly from one amp to the other to ensure consistency.

Specials with this Item

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Warranty and Return Policy

Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider
Sonic Electronix

Summary of Customer Ratings & Reviews

Rating Distribution

5 Star
69%
4 Star
25%
3 Star
6%
2 Star
0%
1 Star
0%

Average Attribution Rating

Durability
4.6
Value
4.4
Features
4.0
Design
4.3
Usability
4.7

Randy

Conway, AR

Overall
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A Professional View

October 7, 2010

I've been a mobile electronics installer for nearly 30 years. The KTP-445 is a nice amp, but the buyer should be aware of its purpose. This amp is not designed to run subwoofers. Its primary use is to improve the response and lower distortion of four typical full-range speakers. Used with modern Alpine head units, it is a simple plug-in installation. Just unplug your radio at the back, plug one harness back into the radio and the other into the harness you removed. That's it! The amp is so small, it will fit behind most radios or under the dash. There's a fair amount of harness to make it easier to locate. You aren't going to experience a great deal more of volume. Remember, practically all head units today already output from 18-23 watts per channel, so this amp is only about twice that and you don't add that to the radio's power, you REPLACE it. Doubling power gives you only about 3 decibels more volume, barely detectable to the human ear. Finally, notice that this amp DOES NOT have RCA inputs. It can be wired to other brand radios, but you need to know what you're doing: Not advisable for the novice.

5 of 5 found this helpful

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Ace

Canada

Overall
Durability
Value
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Usability

Alpine KTP-445?

August 9, 2010

I just bought this, Maybe I should take it back! My Alpine CDA-105 sounds a little better without the KTP-445 installed. Others may have luck with this little amp but not me. Well i guess it sounds about the same as my CDA-105 hooked up straight to the speakers. It doesn't sound like 45 watts RMS, more like 25W RMS x4!

3 of 3 found this helpful

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Nick

Cedar Rapids, IA

Overall
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Value
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Alpine KTP-445

July 21, 2010

First of all, i dont quite hear much of a difference or increase in my sound quality or power. maybe a little, but not much. kind of made me mad that i spent 110 bucks for my CD player not to distort a couple more volume levels. i guess that's why they make 4 channel amps. would not recommend unless you really don't want to put a 4 channel amp together. its kind of hard to fit behind your CD player too with all the wires. but on the other hand. it does sound good!

3 of 3 found this helpful

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Lee

Zachary,LA

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Value
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Usability

Love It

May 18, 2012

I was trying to choose which way I wanted to go with my highs in my 1998 Lincoln Navigator. And I choose to go with the KTP-445. At first I was wondering would this be enough power and after I installed it. I felt in love with it.

1 of 1 found this helpful

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james

shreveport, LA

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Value
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Usability

Decent upgrade!!

April 4, 2012

Before i got this, the speakers were running off the HU. Not hardly an increase in volume, which was expected anyways it since only doubled the power.. So just a few decibel gain.. Definitely clearer though, and door speakers are putting out a lot more bass now, which is an improvement, and i have my gain switch set on low. if you don't have a lot of money to spend on a big 4 channel amp, and you have an alpine HU, i would definitely recommend this.. This puts out more power than some 4 channel amps and its half the price!!!!!

1 of 1 found this helpful

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moneymizthadon

pontiac

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Value
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Design
Usability

Great

April 12, 2014

Great amp got it to to get my bass back after changing my speakers in a 05 impala boy did it do the job my jbl gto928 and gto628 scream now, by the way bypass factory amps for best results

0 of 0 found this helpful

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Michael

Jeffersonville, IN

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It Is Normal for You Not To Hear a Volume Increase

February 17, 2012

First of all, the reason for having this amp is not to hear a volume increase it is to protect your speakers from the possibility of destruction. Generally the radio's built in amplifier is about 18W RMS. To get a just noticible increase in sound volume to the human ear you have to DOUBLE that amount of power. So 18 x2= 36W RMS. To get the next just noticable increase you have to double the power again (36 x 2= 72W RMS) and so on. Each doubling of power is a 3dB increase. The radio volume should NEVER be turned up past 11 0'clock position because distortion is introduced (Clipping of the sine wave peaks). This clipping results in DC applied to the speaker coil and could easily fry it even for short periods of time. The additional booster amp like this one just allows you a bit of "amplifier headroom" so you will not clip the sine wave and thus protect your speaker investment.

0 of 0 found this helpful

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Paul

Chicago, IL

Overall
Durability
Value
Features
Design
Usability

Decent

November 17, 2011

What I like: It's dummy proof. Plug n play. 1 switch for low/high on the back. What I don't like: Lots of wires, and still bulky. You need a lot of room to hide it. What could have been done better: Remote for the switch because you will have to get behind the radio or wherever you mounted this to change from low/high. And some wire loom to make it easier to fish the wire. Other thoughts: it works well, paired with kenwood components and alpine cde-126bt. Volume cranked to 24 and it screams. Without this the volume would have to be at 26 for the same sound. So it does work, well it's meh/ok. The headunit has decent output as it is so if you have a crap headunit it's worthwhile. It is worth the price.

0 of 0 found this helpful

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Buc Nasty

Detroit

Overall
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Value
Features
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Usability

Good value

October 17, 2011

For someone with an Alpine head unit that wants a little more volume but does not want to aliens the cash on an amp kit and rca's, not to mention labor out the extra cost of a conventional four channel amp, this thing does pretty well. I had this in my ride and it did a nice job. Not a ton of features, but of the head unit had cross over ability and you have reasonable expectations for this, it is a great convenient low cost option to improve your sound system.

0 of 0 found this helpful

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Tracie

Frankfort, IL

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Value
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small and easy install

May 6, 2011

I love this product because its small enough to hide behind my dash, no wiring kit necessary so that saves time effort and money. only drawback is only 45rms. its not a lot so if you every get better speakers a bigger amp might be necessary however i could hear a difference in the sound quality. Highly recommend.

0 of 0 found this helpful

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Shi

Canada

Overall
Durability
Value
Features
Design
Usability

KTP-445

May 1, 2011

You might want to get an amp with more power.

0 of 0 found this helpful

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Aaron

Canada

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Value
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Usability

Good product, but has it's limits

December 28, 2010

For what it is, this amp is great. If you want to increase the output of your system with minimal effort (as I did when I bought this) then I highly recommend it. However if you are investing alot in high end speakers, don't cut corners. Buy a Boston acoustic multi-channel amp and some high quality speaker wire and re-wire those speakers! Stock wiring only allows so much power and is always of low quality. If I could do it all over again, this is what I would do.

0 of 0 found this helpful

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brandon

Canada

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Value
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fantastic

December 16, 2010

Highly recommended! Dramatically increases clarity at high and low volumes. Obviously not a competition amp but if you want a simple set up at a great price and quality sound then this is perfect. Currently using amp with stock VW speakers and can't believe the difference.

0 of 0 found this helpful

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BLU RCK

Modesto, CA

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Value
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Great Add...

May 26, 2010

I have this amp installed in my `90 Jeep Wrangler.. I chose it for two reasons.. 1. - compact size.. 2. - good little boost.. It is hooked to the Alpine CDA - 9886M.. I wanted to make sure I had enough power behind the 6 1/2`s and 6x9`s to sound good and it did the job well.. The amp is so small I have it mounted inside the overhead Tuffy Security console with the deck.. Worked out great because I didn`t want a big amp on the floor of the jeep - Space is limited in a Wrangler and amps don`t like the deep water crossings on the trails... =)

0 of 0 found this helpful

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Kvn

Canada

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Value
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Usability

Great Amp

May 7, 2010

Very easy install, fit just under the head unit. Complete plug an play wiring. Adds enough power to give the bass some punch and goes top end clarity. I am using this with an Alpine CDA 9886 Head unit and 2 sets of Alpine SPR 13S Component speakers. This makes for a great sounding system for under a $750

0 of 0 found this helpful

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Ronny

Lexington, KY

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Easy To Install

February 7, 2010

The easiest amp you'll ever install! Adding 45 watts RMS per channel is as easy as plugging in two cables. No amp wiring kits, no running wires, no complicated adjustments. Just unplug the cable from your Alpine compatible head unit, plug the male harness from the KTP-445 into the head unit and the female harness into your vehicle factory harness adapter. The unit itself is small enough to fit behind the radio. I used some velcro and a couple of wire ties to keep it from moving around. The Alpine KTP-445 Head Unit Power Pack gets power, ground, and signal inputs from the existing wiring, amplifies the audio and outputs it through the same wiring. Best of all, it's priced as low or lower than many 2-channel amps. Any Alpine head unit manufactured since 2005 with a black wiring harness is compatible. So if you are considering adding a 4-channel amp, consider the KTP-445.

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Accessory Tools and Products

Accessories added

NVX XBG3PK 1/0 Gauge OFC Big 3 Upgrade Kit

Comes with everything you need to upgrade your power and ground wire.

Your Price $79.99

Belva BBG3KT CCA 1/0 Gauge Big Three Kit

Features everything needed to upgrade factory power and ground wire.

Your Price $39.99

Universal Remote Level Bass Control

Controls bass level and frequency via RCA/Interconnect connectors on any amp.

Your Price $7.99

Small Universal Remote Level Bass Control

The Scosche RLC is a smaller universal bass remote that connects via RCA inputs.

Your Price $11.99

StreetWires FB8

8 Gauge Firewall Bushing

Your Price $6.95

NVX XDBU4 - Top of the Line!

Distribution Block with Two 1/0 or 4 AWG Inputs and Four 4 or 8 AWG Outputs

Your Price $17.99

Professional Installation for your Car Power Amplifier

Covers labor charges through our professional installer network.

Your Price $89.99

NVX XIV45 4-Channel RCA Audio Interconnect Cable

5 Meters (16.4 ft.) 4-Channel RCA Audio Interconnect Cable with Dual Twisted Pair Hyper-Flex Technology

Your Price $23.99

StreetWires ZN7 RCA Interconnect Cable

16.4 ft. of 4-Channel RCA Cable with hyper twist construction, oxygen free copper, and precision machined tips.

Your Price $59.99

NVX XWS1650 Speaker Wire

50 ft. of True 16 Gauge 100% Copper EnvyFlex Speaker Cable/Wire

Your Price $29.99

NVX XWS1625 16 AWG Speaker Wire

25 ft. of True 16 Gauge 100% Copper EnvyFlex Speaker Cable/Wire

Your Price $13.99

Belva BBSW127 12 AWG Speaker Wire

12 Gauge 7 Meter (23 Ft) Speaker Wire (CCA)

Your Price $14.99

Belva BBSW167 16 AWG Speaker Wire

16 Gauge 7 Meter (23 Ft) Speaker Wire (CCA)

Your Price $12.99

SMD DD-1 Distortion Detector

Set the gain of an audio amplifier quickly and accurately

Your Price $149.99

Scosche SPL Meter SPL1000F

Handheld boomSTICK measures your SPL range from 60 to 135 dB

Your Price $21.99

AutoSound 2000 CD-102

High Frequency Test CD specifically designed for the set-up and evaluation of sound system imaging and placement.

Your Price $11.99

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Product Summary

Manufacturer

Model Number

KTP-445

UPC

4958043731008

Weight

2.00lbs

Internal SKU

ktp445

Internal Product ID

22630

Sonic Electronix Wiring Guide

Wiring Diagram Legend

Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

Product Name: Alpine KTP-445