Aftermarket Speakers And Subs Question

[PFF09Sierra]

Ok so I want to change my stock speakers and add two 10" subs under the rear seat. I have the base radio and base speakers. However I want to keep my stock head unit and steering wheel controls. I dont care about OnStar, XM or Speed Volume (whatever you call it) as I dont use either one. My question is do I need two seperate amps? Im guessing there is a specific wireing harness for the steering wheel controls but what is it called and are they all the same? Also, this is a stupid question but how many speakers are there in these trucks....2009 GMC Sierra 1500 Extended Cab

 

Thanks for the help!

[Superperv23]

First off if you are keeping your stock head unit then the steering wheel controls will continue to work fine, you do not need anything else for them. You will also retain your onstar, xm, speed sensitive volume, all of the factory features will remain as you are not removing the head unit.

 

There are 6 speakers in your truck, one in each door and then 2 tweeters in the a pillars. I think you want to power your full range speakers from an amp since you asked about two amps. The easiest way to is buy a RE-Q5 you will see them branded both MTX and Streetwires. Basically you wire the outputs from your factory head unit to this unit and it turns the outputs to rca front, rear and sub so you can use them with an amp. You can also connect amps using the speak leads if the amp has high level inputs but most amps dont so it lowers your selection.

 

As far as amps go you can do one of two things, you can buy a 4 channel amp for the door speakers and a 2channel or mono amp for the subs or you can buy a 5 channel amp that will run the door speaks and subs all in one. The 5 channel is the easier option as far as running power wires and grounds and only having to mount one amp instead of two.

[PFF09Sierra]

Thanks for the help!! I just wanted to get some better speakers to go along with the new subs...do I really need a seperate/5 channel amp for them or can i just use one for the subs. When I was searching people were saying the stock head unit is not powerful enough for aftermarket speakers?

[Superperv23]

You can just use on for the subs and run the upgraded speakers from the stock head unit if you buy speakers that can perform well with lower wattage, something like the JL Audio TR series or Rockford Fosgate prime series would work fine. The stock head unit will not power speakers with higher power handling that are designed to work with aftermarket head units or external amps. You should also avoid trying to run a set of components with a stock head unit and just stick to coaxials.

[emerson1]

You know there are space issues under the backseat. I have an 08 and it was a pain in the ass because of how low it sits and that hump in the middle.

[PFF09Sierra]

You can just use on for the subs and run the upgraded speakers from the stock head unit if you buy speakers that can perform well with lower wattage, something like the JL Audio TR series or Rockford Fosgate prime series would work fine. The stock head unit will not power speakers with higher power handling that are designed to work with aftermarket head units or external amps. You should also avoid trying to run a set of components with a stock head unit and just stick to coaxials.

 

Thanks I think I'll go with the JL's...apprecitate all the help!

 

 

You know there are space issues under the backseat. I have an 08 and it was a pain in the ass because of how low it sits and that hump in the middle.

 

So the boxes specially made for under the seats in the extended cabs wont work?

[Superperv23]

So the boxes specially made for under the seats in the extended cabs wont work?

 

He is likely talking about trying to build a box himself, which would be a pain as the top has to be angled but as long as you get one specifically for 07up extended cab you will be fine.

[Modom65]

You can just use on for the subs and run the upgraded speakers from the stock head unit if you buy speakers that can perform well with lower wattage, something like the JL Audio TR series or Rockford Fosgate prime series would work fine. The stock head unit will not power speakers with higher power handling that are designed to work with aftermarket head units or external amps. You should also avoid trying to run a set of components with a stock head unit and just stick to coaxials.

 

Thanks I think I'll go with the JL's...apprecitate all the help!

 

 

You know there are space issues under the backseat. I have an 08 and it was a pain in the ass because of how low it sits and that hump in the middle.

 

So the boxes specially made for under the seats in the extended cabs wont work?

 

 

 

JL Audio has whats called a Stealth Box comes with the 2 10" JL subs I have it and they are awesome

[PFF09Sierra]

You can just use on for the subs and run the upgraded speakers from the stock head unit if you buy speakers that can perform well with lower wattage, something like the JL Audio TR series or Rockford Fosgate prime series would work fine. The stock head unit will not power speakers with higher power handling that are designed to work with aftermarket head units or external amps. You should also avoid trying to run a set of components with a stock head unit and just stick to coaxials.

 

Looked at their website...whats the difference betweed coaxials and components. They seem to be the same price, the price for the fronts come with tweeters too? Also, whats your opinion on their stealth box (Thanks Modom65)? Seems kinda expensive and I always thought downfireing subs were better?

[emerson1]

There are a lot of custom boxes out there. I just mentioned it because the subs I had picked out were to deep for any kind of box(10" infinity kappa) unless you did major work and raised the seats. The space is definitely workable, but you don't have a 100% open market to what will fit.

[Superperv23]

Looked at their website...whats the difference betweed coaxials and components. They seem to be the same price, the price for the fronts come with tweeters too? Also, whats your opinion on their stealth box (Thanks Modom65)? Seems kinda expensive and I always thought downfireing subs were better?

 

Coaxial speakers are two or more speakers mounted together on the same axes, hence the name, and components are separate speakers often with external crossover networks to connect them.

 

They both have advantages and disadvantages, the coaxial creates all of the sound at one point so that the sound is balanced when you hear it as the high and low frequencies are coming from the same place. Also there is ease of factory replacement without cutting or major rewiring and lower cost. The downside is that while the quality is far greater than stock you get what you pay for generally so coaxials are generally not the quality of components, UNLESS you are looking at a component and coaxial version of the same series from the same company, such as the JL TR series you were looking at.

 

The main advantage of components is the external crossover, which the JL TR doesn't have, this separates the high and low frequencies and in turn produces cleaner sounds as it keeps booth the tweeter and woofer in their operating frequencies. You will also generally find that component sets have higher power handling as they use higher quality drivers and are designed to be run on external amps. The other advantage is quality but that is strictly based on the price price you pay. The disadvantage is that the further speakers are mounted apart from each other you will hear one more than the other creating an unbalanced sound, for instance if the tweeter is closer to your ear than the woofer you will hear mainly high frequency sounds. Most crossovers that come with components have a jumper to reduce the the tweeter volume, refereed to as attenuating, to correct this as most factory locations have the tweeter higher in the vehicle, closer to the listeners ear.

 

With our trucks the distance between where the woofer and tweeter would be mounted in factory locations is so large that it would require that you attenuate the tweeter, either through a built in jumper or by using resistors/lpad. The JL TR does not have built in jumpers so you would have to go the resister/lpad route to achieve perfectly balanced sound. It would still sound ok but the front would seem to be producing less bass than the rear, like it does now. However if you cant tell that it sounds that way now, and lots of people cant, chances are you wont notice with a set of components either.

 

I know this may have confused you even more but either version would work for you and they are the same drivers just either together or separate, it basically comes down to the coaxials you just hook up and they will sounds great but the components you may need to fiddle with a bit to create a perfect balanced sound.

[Doug_Scott]

There are 6 speakers in your truck, one in each door and then 2 tweeters in the a pillars. I think you want to power your full range speakers from an amp since you asked about two amps. The easiest way to is buy a RE-Q5 you will see them branded both MTX and Streetwires. Basically you wire the outputs from your factory head unit to this unit and it turns the outputs to rca front, rear and sub so you can use them with an amp. You can also connect amps using the speak leads if the amp has high level inputs but most amps dont so it lowers your selection.

 

As far as amps go you can do one of two things, you can buy a 4 channel amp for the door speakers and a 2channel or mono amp for the subs or you can buy a 5 channel amp that will run the door speaks and subs all in one. The 5 channel is the easier option as far as running power wires and grounds and only having to mount one amp instead of two.

 

I did the same thing with my truck, but a word of advice, buy the best (highest quality) line out converter. This piece converts the speaker output of your stock head unit into proper line outs. If you cheap out on this one piece, it will not sound very good as any noise you introduce into the system will just be amplified.

 

I am very pleased with the way my system turned out, looks completely stock, all features were retained and it sounds amazing. My total cost was about 2k Canadian. I could have done a very nice aftermarket system for that price, but do not like the idea of having to add in more adapters than I did with the line out adapters.

[PFF09Sierra]

Looked at their website...whats the difference betweed coaxials and components. They seem to be the same price, the price for the fronts come with tweeters too? Also, whats your opinion on their stealth box (Thanks Modom65)? Seems kinda expensive and I always thought downfireing subs were better?

 

Coaxial speakers are two or more speakers mounted together on the same axes, hence the name, and components are separate speakers often with external crossover networks to connect them.

 

They both have advantages and disadvantages, the coaxial creates all of the sound at one point so that the sound is balanced when you hear it as the high and low frequencies are coming from the same place. Also there is ease of factory replacement without cutting or major rewiring and lower cost. The downside is that while the quality is far greater than stock you get what you pay for generally so coaxials are generally not the quality of components, UNLESS you are looking at a component and coaxial version of the same series from the same company, such as the JL TR series you were looking at.

 

The main advantage of components is the external crossover, which the JL TR doesn't have, this separates the high and low frequencies and in turn produces cleaner sounds as it keeps booth the tweeter and woofer in their operating frequencies. You will also generally find that component sets have higher power handling as they use higher quality drivers and are designed to be run on external amps. The other advantage is quality but that is strictly based on the price price you pay. The disadvantage is that the further speakers are mounted apart from each other you will hear one more than the other creating an unbalanced sound, for instance if the tweeter is closer to your ear than the woofer you will hear mainly high frequency sounds. Most crossovers that come with components have a jumper to reduce the the tweeter volume, refereed to as attenuating, to correct this as most factory locations have the tweeter higher in the vehicle, closer to the listeners ear.

 

With our trucks the distance between where the woofer and tweeter would be mounted in factory locations is so large that it would require that you attenuate the tweeter, either through a built in jumper or by using resistors/lpad. The JL TR does not have built in jumpers so you would have to go the resister/lpad route to achieve perfectly balanced sound. It would still sound ok but the front would seem to be producing less bass than the rear, like it does now. However if you cant tell that it sounds that way now, and lots of people cant, chances are you wont notice with a set of components either.

 

I know this may have confused you even more but either version would work for you and they are the same drivers just either together or separate, it basically comes down to the coaxials you just hook up and they will sounds great but the components you may need to fiddle with a bit to create a perfect balanced sound.

 

 

 

Man I wish you lived in Maryland...I would pay you bookoo dollars to help me pick out my stuff and install it Really do appreciate all the help. I'm gonna get some quotes from a few places and see how much this is gonna cost me. I've looked at a few places to order the box from, are they all pretty much the same or do you recommend one type or brand. Also, do I have to go with a shallow mount sub with these boxes? Downfiring or Upfiring? Sorry for all the questions lol.

[temmert1]

I didnt read all your replies so some info may be repeated. I just completed a similar project. I have a 2010 sierra crew, I replaced all 4 door speakers with Polk audio 6.5's. I added one 10 inch sub down firing, powered by a Polk amp. The bass blends nice and is good and tight. I personally think 2 10's will be over kill. Im considering putting an amp on my door speakers. If I do I will go with a 5 channel amp. Yes you can use a 4 channel but you will be running your doors at 2 ohm and sharing a channel thus loosing either front to rear fade or left to right balance depending on how u wire it. You will need at a minimum 8 guage power wire but with a 5 channel I would run 4 or 6. So to answer your question a 5 channel is the best way to go. I used the PAC-AUDIO adapter that plugs right into the factory harness behind the radio. This keeps all factory functions and gives you RCA outs and remote lead to run to your amp.........Another thing to keep in mind if you amplify your door speakers you will also be amplifying your door chime and turn signal.......Thus the volume of these will be controled by the gain on the amp.... Learned that the hard way on my wifes car. I had to turn gain way down. My buddy used to be an installer for circuit city then got promoted to manager. Its a fun project but time consuming. We may be willing to do the install for yah. We are in central pa though....

[Superperv23]

Man I wish you lived in Maryland...I would pay you bookoo dollars to help me pick out my stuff and install it Really do appreciate all the help. I'm gonna get some quotes from a few places and see how much this is gonna cost me. I've looked at a few places to order the box from, are they all pretty much the same or do you recommend one type or brand. Also, do I have to go with a shallow mount sub with these boxes? Downfiring or Upfiring? Sorry for all the questions lol.

 

I never understood the upfiring sub installs myself, in that position the sub is more prone to accidental damage from just general use of the vehicle. Downfiring is arguably the best way to install a speaker as it safer from accidental damage and sound quality wise it has less effects from gravity, that may seem a little nuts but you have something 10" in diameter moving in and out 200 times a second gravity can play a role. So for under the seat applications downfiring is the way to go.

 

As far as the box and shallow mount, well there is not a lot of room under the seat so you are not going to have a lot of volume in the sub enclosure or mounting depth. This basically means either you can buy lower end subs which are not very deep or you can buy higher quality shallow mount subs.

 

If it was me what I would do is put in a single high quality shallow mount sub like the Alpine SWR-T10 which you can find around $240 mounted in a Q Logic QLF-GME110 box around $80 and powered by an Alpine MRP-M500 amp around $150. This one sub would put out more bass than a lot of two 10in combinations, it might seem like a lot for one sub but compared to the price of two sub setup that is not going to preform better it is a good value.

 

The MRP-M500 amp also has speaker level inputs so you can connect it directly your rear speaker leads and not have to worry about a speaker lead to rca converter. In this case you are better just running the speaker input than buying an adapter and using rca's, the amp will process the signal change fine and you will be able to use use the fade on the headunit to control the volume of the sub, although you will turn down the rear speakers at the same time.

 

You will be able to find a suitable way for the remote on lead without using a special adapter, however the best way when integrating to a factory system is to tap into a 12v that comes on with the ignition and run it to a switch then the amp. This way you will be able to turn the sub on and off as you may not always want it on with the radio. As far as power and ground wire you will be fine with 8awg for that amp.

 

The last advice I have for you is when you mount the box you will be drilling through the floor and you want to make sure you that you use some rubber washers in the process. I am sure you are used to seeing people with subs and their whole car rattles which is very annoying, this is mainly because the box is lose and just rattles and therefore everything attached to the panel that is rattling rattles, the sound waves do cause some rattle but the box is often the main cause. So what you want to do is use L brackets screwed to the side of the box that slightly lift the box so it is not resting directly on the truck floor, only the L brackets are. Then it should go bolt, metal washer, rubber washer, L bracket, rubber washer, carpet, rubber washer, truck floor, rubber washer, metal washer, nut. This way will significantly cut down on the rattling and really improve the sound quality.