3rd Gen Sub Replacement

[TahoeDust]

After recently acquiring a '04 Eddie Bauer I set out to upgrade the Audio. I replaced the head unit with a Pioneer AHV-X2700BS and all the door speakers with Kicker KS series 6x8s. I wanted to replace the sub with something that would fit in the factory enclosure and work with the stock amp for now, but would be happy taking some serious watts if I chose to do so later. After a lot of research (thanks to this great forum!) I decided no the Kicker CompRT 8" (40CWRT82). The factory sub is a dual voice coil and the factory amp puts out a dual signal at 1.2ohms & 60 watts. The kicker is a shallow sub that is 2 ohm dual voice coil and recommends 100-300 watts RMS.

Getting the stock enclosure out was not too bad...took about 15 minutes. Here are the steps I took.

1. Removed the plastic trim running along the bottom rear of the cargo area by prying one edge with an interior tool then firmly pulling.

2. Removed the plastic D pillar trim with interior pry tool and pulling.

3. Removed the plastic C pillar trim with interior pry tool and pulling.

4. Removed second row passenger side lower seat belt bolt with a T50 Torx socket.

5. Removed rear passenger 1/4 trim using interior pry tool to loosen all fasteners then pulling up.

6. Unbolted factory sub enclosure (10mm - 2 nuts and 1 bolt) and removed.


Here is a picture of the rear of the factory sub...

Here is Kicker sub wires with the factory harness...

Here is the Kicker sub sitting in the factory enclosure...

I am still trying to decide if I should use polyfill in the enclosure or not. Anyone have an opinion on this? Also, the holes for mounting the speaker do not quite line up so I will need to drill some new ones.

I will take some more pictures as it is going back in the truck that may help others if they choose to swap theirs out.

 

[Anime]

Since you have an aftermarket head unit, you would probably benefit from putting a Kicker amp in there to power the sub. Their smaller 2-channel amps will probably fit perfect in place of the factory amp and should have much lower distortion. They are also pretty inexpensive.

As for the polyfill, that's usually something you see in small enclosures when the volume is actually a little small for the specs of the sub. Some people just use it so a sub doesn't sound too "boomy". Usually the factory subs have a foam-brick-like piece of polyfill in there instead of the softer/loose fabric/craft store polyfill stuff.

You can enlarge the mounting holes slightly so they line up with the new sub, just be sure that you still get a good seal and have enough area betwen the edge of the sub and the holes. An enclosure that leaks air affects the performance of the sub and the sound.

 

[TahoeDust]

Since you have an aftermarket head unit, you would probably benefit from putting a Kicker amp in there to power the sub. Their smaller 2-channel amps will probably fit perfect in place of the factory amp and should have much lower distortion. They are also pretty inexpensive.

As for the polyfill, that's usually something you see in small enclosures when the volume is actually a little small for the specs of the sub. Some people just use it so a sub doesn't sound too "boomy". Usually the factory subs have a foam-brick-like piece of polyfill in there instead of the softer/loose fabric/craft store polyfill stuff.

You can enlarge the mounting holes slightly so they line up with the new sub, just be sure that you still get a good seal and have enough area betwen the edge of the sub and the holes. An enclosure that leaks air affects the performance of the sub and the sound.

Thanks for the reply. I am actually planning on putting a 5 channel amp on the whole system sometime in the next few weeks. I have my eye on this Pioneer... http://www.crutchfield.com/S-Y0TU73EJfqv/p_130GMD9605/Pioneer-GM-D9605.html It should fit under the middle second row seat.

I guess I will see how it sounds with just the "foam brick" material left in it for now.

I think I am just going to go ahead and drill new holes, it should be pretty simple. I am also not sure of the best way to seal the hole in the back of the enclosure. where the factory sub had a bolt running into it.

 

[Anime]

5-channel amps are a good all-in-one solution, and you will definitely get better midrange and highs with a higher power external amp, but systems where the amp is plopped under a seat don't always work out so well, depending how you use your ride. Sometimes it works if you do a clean install and bolt down the amp to a plate or block secured by brackets, but I tend to favor factory-clean installs that use cool-running amps hidden behind interior panels, maximizing cargo/passenger space and keeping expensive audio components from prying eyes. Avoiding a big space-stealing sub box is key, but amps under seats can be a hassle too. Just make sure that the amp placement doesn't interfere with folding the seat down or interfere with anything else.

The factory foam should be fine, I'd only spring for soft fiber fill if the sub specs call for a much larger enclosure and the factory enclosure is too small. Most shallow subs have really low volume requirements, sometimes a factory enclosure is pretty close or just right, so the factory foam might be all you need to keep the boominess away.

I'd suggest just enlarging the existing holes rather than drilling new ones if the pattern is the same.

You can seal the hole a few different ways, the most secure would probably be with a short bolt, two washers, and a nylon locknut and some black silicone or other RTV silicone sealant, putting the sealant around the hole after putting one washer on and sticking the bolt through from the back, then putting the other washer on and tightening the locking nut so it's snug. Should give an airtight seal and won't come loose. You could also find a similar piece of plastic like what the enclosure is made of, and epoxy it into the hole, putting a circular piece over the inside and outside as well for additional strength.

 

[TahoeDust]

5-channel amps are a good all-in-one solution, and you will definitely get better midrange and highs with a higher power external amp, but systems where the amp is plopped under a seat don't always work out so well, depending how you use your ride. Sometimes it works if you do a clean install and bolt down the amp to a plate or block secured by brackets, but I tend to favor factory-clean installs that use cool-running amps hidden behind interior panels, maximizing cargo/passenger space and keeping expensive audio components from prying eyes. Avoiding a big space-stealing sub box is key, but amps under seats can be a hassle too. Just make sure that the amp placement doesn't interfere with folding the seat down or interfere with anything else.

The factory foam should be fine, I'd only spring for soft fiber fill if the sub specs call for a much larger enclosure and the factory enclosure is too small. Most shallow subs have really low volume requirements, sometimes a factory enclosure is pretty close or just right, so the factory foam might be all you need to keep the boominess away.

I'd suggest just enlarging the existing holes rather than drilling new ones if the pattern is the same.

You can seal the hole a few different ways, the most secure would probably be with a short bolt, two washers, and a nylon locknut and some black silicone or other RTV silicone sealant, putting the sealant around the hole after putting one washer on and sticking the bolt through from the back, then putting the other washer on and tightening the locking nut so it's snug. Should give an airtight seal and won't come loose. You could also find a similar piece of plastic like what the enclosure is made of, and epoxy it into the hole, putting a circular piece over the inside and outside as well for additional strength.

If my measurements are right the Pioneer amp I linked should fit under the middle seat of the second row. That seat does not fold forward and the placement should not get in the way of either outer seat folding and allowing access to the third row. I plan on bolting it in securely. I am really all about a clean install, but it seems like very few 5-channel amps use fans and a passively cooled amp behind interior panels concerns me.

I do not think that just enlarging the holes will work for me. The diameter of the hole pattern of the new sub is about 1/2" larger than that of the factory sub.

I was thinking about just epoxying a piece of plastic over the hole as you mentioned, but a short bolt/nut and two large washers and RTV sounds like a better solution...I'm going to see what I can dig up in the garage.

I'll post some more pictures as it comes together. Hopefully I will get a chance to play with it some tomorrow.

 

[Anime]

That 5-channel amp is a Class D amplifier, which means it is more efficient than traditional Class AB amps, and so it runs cool rather than hot. The downside to Class D amps is some people say the sound is more tinny or not as full as a Class AB, but it probably doesn't matter as much in non-audiophile systems. I have Class AB amps behind the rear panel and they are fine since there is plenty of airspace behind there and I am not hard driving 12" subs at high volume or low ohm loads, even class AB amps can be decently efficient at 4 ohms.

The bolt/nut is a good secure option if you have enough space behind the sub. If you don't have any room to spare behind the sub or behind the enclosure when installed, the plastic discs will work.

Do what you gotta do with the holes. You can fill the factory holes with that same Black Silicone or whatever RTV you get if they might leak air around the sub rim. Use tape on the backside of the hole so it doesn't drip through but take it off after it cures so you don't have tape come off and fly around inside the enclosure.

 

[TahoeDust]

These are pretty much the three amps I have it narrowed down to. I can get them all for close enough to the same price that the cost is not a factor between them. The Pioneer is the most powerful, and power is good. I love their head units, but I do not know much about their reputation with Amps. I know Rockford Fosgate is supposed to make a solid amp, and have also heard good things about Kenwood. Thoughts?

http://www.crutchfield.com/p_130GMD9605/Pioneer-GM-D9605.html?tp=35808

http://www.crutchfield.com/p_575R600X5/Rockford-Fosgate-R600X5.html?tp=35808

http://www.crutchfield.com/p_113KAC7005/Kenwood-KAC-7005PS.html?tp=35808

 

[TahoeDust]

I just come across this deal...it may be too good to pass up....

http://www.amazon.com/Rockford-Fosg...ie=UTF8&qid=1452716921&sr=1-1&keywords=r600x5

 

[Anime]

You should take into account the RMS power ratings of the speakers and sub you have before just buying any amp. You want the amp output at 4 ohms to match or be slightly below the RMS (continuous) power handling of the speakers and sub, otherwise they will blow and you'll have to buy new stuff.

The 2 ohm dual voice coil sub can be wired to present a single 4 ohm load from a mono-sub output, but the power handling stays the same, a sub that can handle, say, 250W per coil at 2 ohms can only handle 250W when wired for a 4 ohm mono channel.

Pioneer makes okay amps, I like their stuff, but some of their amps tend to have more THD (distortion) than I feel is acceptable, given the price and the reputation of the company. There are plenty of quality audio companies that put out amps with less than 0.01% THD, so 0.1% isn't bad, but 1% is just unacceptable.

Kenwood is similar, big company with a good reputation, just not putting out the quality they should be for the price. Same issue with distortion, too.

Rockford Fosgate is okay too. They have a reputation as a more 'enthusiast' brand, I can't say I like a lot of their stuff, but the specs seem decent.

I would go with the amp that goes with the power ratings of the speakers and sub you already have, though getting a deal on it would be nice too.

 

[TahoeDust]

The bolt, stop nut, two large washers, and RTV worked great to seal the hole in the back of the enclosure. I also used a little RTV to seal all the existing sub mounting holes even though they were all covered by the foam backing of the Kicker sub. I just used some self tapping screws to mount the new sub. Overall I am pretty pleased with how it sounds, even with the factory amp. I am looking forward to hearing it with the new amp.


Here is how it looks and sounds in the car...
http://youtu.be/Nuw5cY362nM


Here is how the sealed hole turned out...

 

[Anime]

Looks good.

When you get the new amp, I would use thicker gauge speaker wire for the sub (10 or 12 AWG isn't a bad idea), and use a file to round off the sharp edge on that area where the speaker wire goes behind the sub rim, so the wires don't get crimped in or the sheathing doesn't get split on that edge. Very little chance of it shorting out on the plastic, but not worth the risk of it contacting the metal sub rim or even a strand or two of the positive/negative wires making contact.

You might also consider a new foam piece for sealing the wires, maybe cutting a strip to place on top of the wires as well so the foam ring around the sub isn't the only thing sealing the top part of the wires. You can also make a custom "plug" with RTV by putting down some plastic wrap (or cutting up a clear plastic sandwich bag or using painters tape), putting the wires into position, putting RTV under and over, then putting something flat on top and taping off the ends to contain the RTV so it doesn't run. When it dries you'll have a form-fitted "plug" that wont be stuck to anything but the wires.

The enclosure probably doesn't need to be that airtight, but the Kicker sub will benefit more from a less leaky enclosure than the factory sub.

 

[Jason94sport]

Bumping to say thanks. I did the same thing this week. Sub changed models but still the same as far as I can tell. Sounds much better. Long bass lines are not bottoming out like the stock one. It's not going to rattle windows, but inside it sounds good. Note on my radio anyway, I had to reveres sub polarity. I even have the stock speakers still. Working on that upgrade next.