kevint1022

I recently ordered the Alpine KTP-445U (new universal of the ktp445 original) for my stock head unit for my 07 F150 super crew. It has not arrived at my house yet so I have no clue how the set up will be or how powerful it is. I remember reading how great the original is and how it really helped bring others speakers to their full potential. I was thinking about ordering a pair of Infinity Kappa 50.9cs components for the front doors and a pair of Infinity Kappa 682.9cf for the rear doors. I was wondering would the Alpine amp be enough to power the speakers to their potential? Thanks.

http://www.crutchfield.com/p_108509C...pa-50-9cs.html
http://www.crutchfield.com/p_1086829...a-682-9cf.html
http://www.crutchfield.com/p_500KTP4...p445u&skipvs=T

NOTE: I am definitely not getting any of these from Crutchfield. That site is way too pricey compared to eBay! Also not sure why the 445U is not available on Crutchfield, but other sites like BestBuy it is available for shipping.

ibd2328

iTrader: (2)

I mean, it will be a decent upgrade from stock or just an aftermarket HU. Will it be optimal, definately not. Those comps are rated at 85 for each pair, so I would say optimal is from around 70-80 or so. I had the older version and wasnt too impressed with it. There is no replacement for a true outboard amp and a 24db/octave cross over.

kevint1022

Thanks for the quick reply. Hmmm that's pretty disappointing after reading about all the raves on it from Crutchfield and this site. So you would recommend buying another amp for that system and if so what is your recommendation? I would like to keep my stock head unit.

ibd2328

iTrader: (2)

Sure the small size and quick connections made it idea for quick installs. However, the draw backs are not as good SQ, high sloped 12db crossovers, and minimal power gain. I highly suggest people with mid- to high grade components switch to a true outboard amp. The gains, clarity, and power will be much more substantial.

Typically an amps power can be directly related or derived from the ga. of wire using to power it. Obviously, if its only running off 12ga. wire the draw from it could not be to great. You surely don't want to starve your new components from their true potential.


I used a Focal FPP 4100 for mine, but its a bit pricey.

My second choice was the Rockford Fosgate T400 - 4. Great power, 24db/octave, good SQ, and you can prolly pick one up used for about 60 more bucks that the KTP new.

Remember:
Amps = Watts/Volts and Watts = Amps x Volts

kevint1022

Thanks for all the help, I'm not really that knowledgable with systems! I started to second guess my purchase after I saw full sized amps for similar prices as the ktp445u. I will probably try and return and go with another amp like the rockford! I would be able to keep my stock head unit with this amp, correct?

ibd2328

iTrader: (2)

It will require a LOC to be added. Usually i suggest an aftermarket HU for a good SQ system. I know it takes away the OEM look, but the signal it produces is much more clear than any LOC will offer.

JoeBoost

Great amp.

I honestly cant understand why there is so much popularity with the KTP-445 when as ibd2328 states so much more can be had for little more investment. You could easily put 100w/channel to those speakers all day long and it will sound significantly better than under powering with this small amp.

I looked briefly at the specs on the KTP-445 and knowing Alpine (I have 2 PDXs) its a class D amp which have on average have an efficiency range of 65-80% at max output. So the math tells me that all said and done you are probably getting about 30-35w/channel at best. I also dont see how this amp stuffed in a dash can dissipate any heat so when that little guy warms up expect that output to drop further.

Im sure it is a marked improvement over the stock HU w/no amp but why sell yourself short?

slowrey

Many people want a boost over stock without having to invest in many things other than an amp. Think about it, with an amp you have to buy an inline fuse, power cable, RCA Cables, ground cable, distribution block for both, LOC perhaps, speaker wire etc. When with the KTP-445 you need that and a BT-5520. That's all.

$150 vs $400+ or 30 minutes vs. 4-5 hours. Enough said.

ibd2328

iTrader: (2)

If you want a little boost over stock sure, go ahead and spend $150 on ktp. You could give me the argument that its good for lower wattage speakers, and I would still disagree. There is a huge difference in CLEAN power, and power(watts) in general. I've had both; the newer and older versions and both were disappointing given the hype and reviews.

I had the older version in a BMW pushing a couple of small 4" components only rated to handle 45 rms. After about 1/2 volume you could tell the ktp was running out of juice. Honestly, do you think an amp with a 12ga. power cord is going to put out 200rms efficiently? If so, a few electrical classes should be taken before you do your install.

Before you spend 150 bucks on something of minimal significance, upgrade headunits, get a different amp, or keep saving.

I wouldn't be saying any of this if the KTP was leaps and bounds over an aftermarket HU. To be quite honest, I could tell minimal difference in the upgrade from my Alpine CDE 123 to the Ktp 445.

I wont even get into the xovers, octaves, bandwidth, and such. No comparison to a true 4-channel amp.

As always in car audio, you get what you pay for. None the less, a 4-channel amp can be had for much less that 400 including wiring.

Raptor 701 Rca's x 2 = 20.00
4ga. welding cable x 15ft. = 25.00
14ga. speaker wire x 80ft. = 15.00
any ga remote wire x 15ft = <5.00
= $65 + amp of your choice.

note: the amps below are mid grade, but for the price offer un-paralled SQ
http://outlet.crutchfield.com/p_675F...0-4.html?cc=01
http://www.ebay.com/itm/ROCKFORD-FOS...ht_4015wt_1270

So the Rockford P400 and wires can be had for a little more than a 100 over the KTP. Sorry for the logistics, just trying to prove a point.

Not trying to be rude to anyone here, but I think the KTP is geared more towards the installers who are confused as to how a 4-channel amp works or is set up. The plug and play/ splice is fairly simple and attractive to most new comers to the audio industry.

ibd2328

iTrader: (2)

Touching on the wire protection.
Inline fuse blocks, distribution blocks, etc. can all be made from (2-bolts, 4-nuts, and 4washers). About 2 bucks at your local hardware store. Add a couple of 100amp ANL fuses for 2.99 and you have a whopping total of $5.00. All my fuse blocks and dblocks are built this way with 1ga mining cable.


Grab a piece of wood, drill a couple of holes so the bolts fit and hold the fuse on one side. Flip it over, screw down the nuts to pull the fuse against the wood and connect the power wire to each of the respective bolts, then screw it down. Fairly simple, and very effective at transferring current.