I've pretty much decided to get 1 4 channel amp (Kenwood KAC-849) to power all 4 speakers in each door and could use some advice.
1) What is the best place to install the amp in my 2003 supercab?
2) Am I better off replacing the stock speaker wire?
3) Also.. Anyone have any good wiring diagrams or articles for how to best run the wires? It's been 15 years since I've installed a system and I'm WAY rusty.

I'll also be installing a self powered sub box under the back passenger seat, so that needs to be considered also. I'd really like to hear some of the great solutions you guys have come up with.

Again, thanks for the help!

 

Personally, I would not recommend the Kenwood amp...I'm sure there isn't anything wrong with it, but I havn't been impressed with their amps. Of course, I'm not into the mainstream brands when it comes to amps & subs...

The best location to mount an amp would be under the driver's seat, just make sure it isn't over 2 1/4" high so it will clear the seat adjustment bar.

Definitely run new speaker wire (16 awg or thicker) from your amp to your speakers. Do not use the factory wire with an aftermarket amp!

 

 

Wow, you guys have me 2nd guessing my decision on Kenwood amps.
What would you recommend for my budged of about $200 -$250

I was leaning toward simply plopping in stock replacement speakers, but you have me wondering about that decision as well. Keep in mind that I don't have the $$$ for a professional install, my total budget is about $1000 so I have to be careful (I'm also a noob at this)
If I do go with Components up front, again what would you recommend?

I will be replacing the stock speaker wire, that just seems like a no brainier.

Thanks for all the great advice, and thanks for helping this noob.

 

There is nothing wrong with Kenwoods, 2Trucks was just saying he wouldn't recommend them. There are lots of good amps out there both mainstream brands and others. I have some Kenwoods that have been kicking around for 11 years and since I have no extra cash laying around I'm not going to replace them until they die. They have performed well and done well in competitions for me so I can't complain about them at all. That being said nowadays for the same money there are some better alternatives for about the same money so look around.

I would also as has been mentioned spend some money on good seperates for up front, that will make all the difference, in anything other than a crewcab I wouldn't bother with rear speakers.

Wiring you need to run new wire for the speakers, 16 awg is fine. There is also no need to go any bigger than 8 awg for the amp. Run the power wire on one side of the truck the speaker wire on the other.

A $1,000 to spend can get you a very nice system. You didn't mention if you already have an aftermarket HU already. I am assuming you do. So that 1K can buy you some nice components and an amp.

Search through the threads here, there is a lot of good information. In the end for the speakers it is what sounds good to you. Don't buy speakers based on what someone else sounds good or you may be disappointed. Visits some audio shops with your own cd's and listen to the speakers then make your decisions based on your preference.

Good Luck!

 

gojo -

Install the amp where it is easiest for you to secure properly and hide it from view. In the limited space inside a truck, it's all about the same as far as wiring, etc. Cooling should also be a factor in your decision. I don't have my amp under the driver's seat because I keep another item under there...

BTW - I have not had a bad experience with Kenwood amps. They appear to perform as advertised. I just don't like their tendency to use "marketing" ratings instead of RMS ratings. However, I looked at the amp you are considering and I think it will perform fine, especially with 5x7 Infinity speakers.

I took the liberty of posting my response to KYFordFreak regarding this exact issue:

If you want to keep your OEM connectors, Circuit City, Best Buy, Tweeter, etc. all have harness adapters that give you "flying" leads from the factory harness - no cutting. I personally just cut mine off and tinned them with solder before connecting them to the crossovers.

I know this will sound like blasphemy to some of the "audiophiles" that lurk around here, but what gauge speaker wire you use is of little consequence at the wire lengths and power levels applicable to a vehicle (excluding subwoofers).

For example, lets say you are going to push 100 watts to each and every door. Lets say the speaker is a 4 ohm load and the wiring from the factory is 16 gauge and the harness is 15 feet long from HU / amp to the speaker. Using those parameters, you end up with:

20 Volts RMS (average) dropped across the speaker
.12 ohms resistance of the speaker wire itself
4.854 amps of current flow (average) through the speaker
5.74 watts of lost power, measured at the speaker
-0.26db loss of signal, measured at the speaker

What does this mean? 16 gauge wire is more than adequate to handle the loads presented by a 100 watts amp into a 4 ohm speaker.

Lets say you wanted to use 12 gauge speaker wire instead. Here's the numbers:

20 Volts RMS (average) dropped across the speaker
.048 ohms resistance of the speaker wire itself
4.94 amps of current flow (average) through the speaker
2.36 watts of lost power, measured at the speaker
-0.10db loss of signal, measured at the speaker

As you can see, the gain is extremely small for the added work, complexity and cost of replacing the speaker wires. At any listening level, it would be inaudible. You would be better off investing the time and energy into getting a power amp to drive those new MB Quart components. (BTW, I installed those exact speakers in my friends car. They are quite good. I'll bet you will be pleased. He is driving them with a 40 watt per channel Kenwood amp and they ROCK!!)

As a side note, because human hearing is not linear it requires 10 times the power to make a given signal sound twice as loud to an average group of listeners. In other words, if you are playing music at 10 watts RMS constant, it would require 100 watts RMS constant for 90% of a given population to declare it was twice as loud as the 10 watt level. That is why losing a few watts to smaller wiring is not an issue.

As far as damaging the MB Quarts, the following is true for most any quality speaker: Too little power will damage them easier than too much (within reason). When you overdrive an amplifier, it begins "clipping" which, loosely translated, means the amp is no longer producing the variable signal of music, but rather a straight line DC current (much like a battery). This is especially damaging to tweeters, because their small voice coils cannot handle the DC current for any appreciable amount of time.

Anyway, so much for the the math and data behind the wire: You need to decide how important the wire sizes are to you.

Let the flaming begin !!!!

Run RCA cables from your new Alpine HU to the amp. Run the speaker outputs from the amp up to the dash and use a harness connector to plug them into the factory wiring. Change the speakers in the doors and you are done. No schematics needed.

I built a custom enclosure for my subs, and am powering them with an outboard amp, so I can't help you there.

I'll post my sig so you can see my parts list.

Good luck !

 

In B-Man's installation.. running the speaker wires from amp back up to the head unit.. you have to run the speaker wire right by the door anyway so why not just feed it through directly to the speaker?

1) your wire run will be shorter = less resistance = less loss (though its still a minimal difference as B-Man has shown)
2) it isn't THAT difficult to feed the wire into the door... you've gotta take the door panel off anyway to install the speakers; why not just feed your speaker wire in while you've got the door panel off.
3) the cost of a few more feet of speaker wire is minimal.
4) An increase of 3 gauge numbers (e.g.: 11 to 8) roughly doubles the cross-sectional area and cuts electrical resistance in half, thus greatly increasing ampacity.

I believe your calculations B-Man.. but I had to find some reasons to justify my NOT using the factory wires in my installation.

 

i'd get jbl 1200.1 - about $200 - $250. loud as hell pushing dual 12" kickers.