Butch Brown

I am going to try putting a JL Audio 8w3v2 d2 in the front door and wire it for 1 ohm to the factory amp which is 1/2 ohm 100 watt. I have it in the trunk now driven by a Rockford Fosgate Punch DSM-200 amp bridged wired 4 ohm, the amp is also driving the rear speakers, MB Quart 6X9 components, but I am wondering how well the sub will work in the front door. Theoretically at 1 ohm it would get 50 watts since the Boss speaker is getting 100 watts at 1/2 ohm but I think it will actually get 60 - 70 watts at 1 ohm. When I get time I'll try it since I have 6X9 4 ohm blaupunkts that I want to put up front I might as well try the sub while I have the door apart. Any comments appreciated.

lesper4

iTrader: (3)

well if it works you will need to dyno matt the HELL OUT OF THE DOOR for it not to shake.

Jedi54

iTrader: (7)

door rattle is pretty bad already, I'd be careful about putting something like that in there.
Take a look at something like this.... https://www.rx8club.com/series-i-interior-audio-electronics-24/focals-jls-lc6-install-done-92208/

Butch Brown

Yeh I think your right, like there aren't enough rattles already!

Butch Brown

I'll still try it while the door is off. I get allot of bass out of the MB Quarts in the rear and I think the Bose in the front are actually woofers so maybe it won't be much different, I just want to get rid of the mud that comes out of the Bose.

MrWigggles

Butch,

Let me help you out if I can. I did a full 5.1 install in my car and I did get 8" woofers in my doors:

https://www.rx8club.com/showthread.p...ighlight=focal

Here are a couple pictures:



and a close up of the driver's side.



My installation is a sealed installation and I wish I had detailed pics of what my installer had to do to get enough airspace (.35 cubic feet) for an 8W0. He had to create a dual chamber fiberglass enclosure that worked its way around the window. It was very tricky.

You can go that route and get fantastic results or you can go free-air as it sounds like you are doing. If you go free-air just remember that the "muddiness" of a woofer in the doors is both due to the quality of the driver and even MORE importantly the quality of the enclosure.

Low frequency bass loves to cancel itself out and there is no better example than the common door enclosure. When the woofer pushes in, it pressurizes the enclosure . Ideally an enclosure (say made out of concrete) would resist the pressure and not expand at all, but a common car door can't help moving. So when the woofer sucks in, the door pushes out and vice-versa when the woofer pushes out the door sucks in (a little). The effect happens at low audio frequencies and end the end generates cancelling audio waves. To illustrate my point, when you rest your knee on the door and feel the bass coming from the door panel, that bass you feel isn't "extra" bass it is actually out-of-phase bass that is canceling out the woofer's intended bass.

The only good way to fix the problem other than having someone build fiberglass enclosures in your doors for you (it took Lee, my installer, a full day for each door), is to use dynomat or a similar product to make the doors nice and solid. You aren't strengthing the door really you are just making the panels heavier and thus more resistant to the expanding and contracting I described above.

There is one more option and it is the only one you should definitely not do: build an enclosure in your doors that is too small. If you think you can get enough airspace with a simple enclosure, think again. The worse thing you could do is build an enclosure that would be too small for your 8" woofer. (Please note that the JL 8W0 has to have a medium sized enclosure; it can not be used in a small enclosure or free-air. Other 8" woofers might be the opposite in that they have to run free-air and can not be in enclosures.) Woofers in small boxes sound terrible.

Well that's my long-winded explaination and if you want to discuss it further I would be happy too. Good Luck. Please remember that new drivers are only half the battle; you have to have a good enclosure as well.

-Mr. Wigggles

Ps. This is probably the most important thing. I have a pair of 8W3v2's in my garage because they simply wouldn't fit. My installer tried every trick in the book and could only get 8W0s in the doors. 8WO's are fine for any reasonable midbass work. I still have a sub to do the heavy lifting (50Hz and below) in my trunk.

1145climber

mr. wigggles, youre my hero

Butch Brown

Mr. Wiggles,
I'm not sure exactly why you couldn't use 8w3's they take almost the same size enclosure as wo's. My biggest question is how well they would be driven by the factory Bose amps in the front doors. The WO would probably do better since it only requires 75 watt optimum RMS compared to W3 125 watt optimum RMS. I know they should be in an enclosure so if I connect one to the front door Bose amp while in my home built enclosure and it sounds good I will figure out how to build an enclosure in the door, otherwise I will just try the 6X9 Blaupunkt overdrives connected to the Bose amps. I don't intend to rewire at this point but if the Bose amps don't work well I may use my PPI 4X80 amp to drive the front and rears (MB Quart RCE-269). The rears are now driven by an old 1973 Rockford 150 watt per channel amp. The 8W3 is bridged to that same amp and it provides enough base now. Your system appears to be ideal but I'm not about to spend $3500.

forbidden

One thing that you may not have considered and at the same time noticed in Mr. Wigggles install is the addition of a midrange driver. Fire any 8" you want in there but you then need to address the midrange response at the same time. If you look close at his door panel you will see a new black grill cloth panel added above the stock speaker grill for his midrange.

The factory Bose amps in each door are tiny little suckers. While what you want to do may indeed work, I would not expect it to work extremely well. There is something to be said for trying something yourself though, you will always learn from the experience.