1967 Gto car audio subwoofer set up

I’m currently setting up my stereo. Getting closer after like a two year break from third child.
Running
(2)jl audio 12w6v2/v3
xd1000.5 amp 1000w

How should I set this car up for super high end bass.
How would I run the box, sealed or ported?
Should I run one box or two? And where in the trunk?
I would love to put facing out under package tray and rear seat but not sure if there is enough space and volume because of the rear differential hump in sheet metal.
Where to put front speakers. I tried the speaker kickpanels but they don’t fit and the speakers are cheap. Should I put them in door?

Subscribed

From the picture, it looks like your car is a coupe? What is high end bass? Loud? or well rounded response and sound quality?

The XD1000.5 is a good amp, but not a great choice if youre powering TWO W6's
a 12W6 is dual 4 ohm, so you can wire it to 2 ohm or 8 ohm. The XD1000.5 will do 600W @2ohm. running two will either put the amp into protection mode (1ohm) or under power them (4 ohm)

If it was mine and I was using the equipment you have it would do this:
run 1 W6 firing through the rear deck in a sealed box. (Not sure if TheShopLLC sells a 12" version of their under-deck box, but the 10" ones are killer)

If you want to keep it all JL,
JL C2690X 6x9's for the rear deck
JL C2650 6.5" components in the kick (again, TheShopLLC if they have kick's that will fit your car) or in the door if you dont mind cutting.
Tweeters in the top of the door, again if you dont mind a little cutting and fab. OR if that car had factory speakers in the corners (not the center) of the dash pad, put them there.

Not sure what your source unit is, but Id sell the other W6 and buy the JL TwK88 to EQ and time align it.

Keith:

In the car audio world there are very different philosophies when it comes to the low frequencies and sub woofers. There is the sound quality (SQ) approach where the goal is accurate frequency response, not maximum sound pressure levels (SPL) and then there is the competition (comp) approach where it is all about max SPL, and thunderous bass. To answer your sub-woofer questions I need to ask some questions for you:

1. What do you consider "super high end" bass? Are you looking for tight, punchy bass or do you want the max SPL, loud bass that rattles the car next to you?
2. Do you have enough room to put the sub in the rear deck, or do you want the sub hidden in the trunk.?
3. Are you handy with power tools? Could you make your own sub box or do want to buy an off-the-shelf box?

Generally speaking, sealed sub boxes sound tighter and more controlled than a ported box, but the ported box will be louder especially at the tuning frequency of the port. This is why some car systems have peaky bass response where a particular bass note sticks out above the others. It is also much easier to blow out the driver in a ported box than in a sealed box because the ported box doesn't have any air pressure behind the speaker cone to protect it from traveling too far and breaking the suspension (of the driver, not the car). A sealed box uses the trapped air behind the cone as a spring to protect the driver from traveling too far, this is also why sealed boxes sound tighter and more controlled.

You asked about using a single sub or running two subs. In a sound quality install, 1 sub is better than 2 unless you mount both drivers in the same box. You will get comb filtering, (frequency cancellation) when you install 2 subs in separate boxes because the sound waves from each sub interact in a way the cancels out certain frequencies. This effect is less severe when the 2 subs are facing the same direction and installed in the same box.

If you are handy with power tools and you want the tight, punchy bass from a sealed box, I would mount one, single sub in the middle of the rear deck and make a custom box behind it out of 3/4" plywood. I would make a template of the rear deck and cut a 1/2" or 3/4" piece of plywood to glue and screw to the entire rear deck to tighten up the sheet metal so it can't rattle and vibrate. You can also mount the amp to the back side of the box facing the trunk where it will be easy to route the wiring and adjust the filter settings and gains. The other nice benefit from the custom box I just described is everything is bolted, screwed and glue in place; it won't be sliding around in the trunk every time to take a fast corner or make a hard turn. If you lack the fabrication skills or the power tools to do a custom box, I would still recommend a single driver box that you can put in the trunk but it needs to be bolted down for safety. JL Audio recommends the 12w6v3 sub to be installed in a 1 cubic foot box for a sealed enclosure, and a 1.3 cubic foot box with a port tuned to 33Hz for a ported box.

For the front speakers, you can install coaxial speakers in the doors, preferably ones where the tweeter can be adjusted to point upward toward your ears, not your ankles. You really don't need big speakers and you should roll off the low frequencies at about 100Hz to let the sub handle the low end. 5-1/4" or even 4" speakers can sound really good with a powerful sub in the back. Component speakers (where the woofer and tweeter are separate drivers) typically sound better and have better crossovers to divide the frequencies between the highs & lows, but these will require 2 holes in each door.

If you're a purist who doesn't want to cut up his classic car, you can install a single 4x10 speaker that has 2 tweeters (L & R) in the factory dash location. RetroSound make a nice high powered, dual voice coil, 4x10 speaker that sounds pretty good although the tweeters are not that great and the stereo separation is poor because all the sound is coming from the center. It's definitely a compromised but you get some kind of stereo image up front without cutting up your car. If you have a factory AC car you will need to get a slim speaker (RetroSound has one R-410N) that will clear the center AC ducts behind the dash. I'm doing an install right now into a '72 Olds 442/Cutlass convertible that is using the RetroSound speaker in the factory location and 2 small 1/2" tweeters mounted in the dash at the A-pillars. The tweeters in the RetroSound center speaker have been disconnected so the tweeters at the A-pillars will handle the high frequencies to create better stereo separation and image. The tweeters will be mounted in the metal part of the dash forward of the dash pad so it's a pretty stealth install. One caveat is the windshield needs to be removed to drill the holes. I did sound check, test mock-up and it sounds better than I expected.

If you plan to put 6x9 speakers (or any speaker for that matter) in the rear deck you should also to roll off the low end at about 100Hz so they don't compete with the sub and cause the comb filtering I mentioned earlier.

I hope this info is helpful,

Rodney

Great response, Rodney!

I agree too with getting the sound from the subs directed into the interior and not allowing it into the trunk. While it looks nice opening the trunk and seeing subwoofers, when they play they create sound waves to where you can get some nasty rattles at louder volumes from the three point mounting catch setup on your trunk lid. Not to mention possible license plate rattles, vibrations getting transfered to the amplifiers circuit board components and also a reduced sub volume. I've heard way to many cars with the trunk lids rattling or license plates rattling and to me it's worse than having an exhaust leak as it sounds like junk. To me putting a sub in a trunk and having it filling up the trunk with sound and not so much the interior where you will normally will be at is like putting a home sub in a closet and closing the door. Granted bass will go through a lot of things but the less it has to go through the more sound you should get. Also if you fire the subwoofer up towards the angles rear glass you may get some additional output VS firing the sub sounds through the rear seat frame and metal backup panel.

Onto something else, is if that battery in the trunk is also used for starting you car and is the only battery planned on, please fuse the wire going forward up to the starter and the rest of the car (and maybe it is already but I cannot tell due to the photo angle).

Also too if you are leaving a battery in the trunk, please enclose it and vent it to the exterior of the car. If something screws up with the alternator and overcharges the battery, the trunk could become filled with explosive battery fumes with how the battery is now in your original photo and all it might take is a spark to light things up. Also do not be confused that batteries like Optima's do not need to be in a vented enclosure when in a trunk. They too can vent fumes out of them.

Jim

Attachment 174977Thank you for everyone’s responses. So informative. I decided to use some advice above. I’m going to sell the 12w6v2 and keep the 12w6v3. I will keep the xd1000.5 jl amp and supply the 500-600w to one sub. As for the door speakers I will check out the jl recommendations from above. I just had an idea and it was installing the sub in the interior and make a custom center console that will house a sealed enclosure. I have the space and I think it would look unique being in the cabin. I bet the bass would sound amazing too.

I agree with Rodney's thought and ideas . As for a box , I'd recommend a band pass design box ported thru the rear deck. The port can easily be covered with mesh or speaker cloth

Just measured and that space is too small. Back to the drawing board

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Originally Posted by keith4909

Just measured and that space is too small. Back to the drawing board

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6 months later, what did you come up with?

My audio guy has been backed logged due to other projects parts failures. I hope to get in the first or second week of the new year.

One subwoofer 600 watts i’d go ported. Wire woofer parallel (2omh). It also depends on the music you listen too. Rap, R&B, EDM..... id go ported. Most other sealed

Being an audiophile myself, I’d like to know the rest of the components being used, and what has been done to the vehicle. If the car has a 1500 hp engine and no sound deadening, you aren’t going to hear much with 1200 watts. Also, if there is a 2 5.25s in some kick panels and nothing else, there is so much unbalanced audio going on, then I can only recommend an 15 incher in the truck with a 5 foot box ported to around 32 htz

Here's my build in my 70 Chevelle. It has 2 10s ported through the rear deck in a bandpass box. If could do it over I'd only use one, there is no rattle nice clean bass.

Attachment 183041[ATTAC
H=CONFIG]183042[/ATTACH]Attachment 183043Attachment 183044

Nice set up. I ran it with one but liked how it was with 2.

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Originally Posted by lawrenq

Here's my build in my 70 Chevelle. It has 2 10s ported through the rear deck in a bandpass box. If could do it over I'd only use one, there is no rattle nice clean bass.

Attachment 183041[ATTAC
H=CONFIG]183042[/ATTACH]Attachment 183043Attachment 183044

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This is what I pictured for my old-school Buick. Clean and looks well thought out. Why would you go with one if you could do it over? I currently have two kicker LS7 Q series 12's w/ cxa1800.1 kicker amp. My car is at the audio shop as I'm typing getting sound treatment. Any advice before I drop this bag off. Plan is (2) 4" morels in center dash, (2) 6.5" morels in kick panel, (2) 6x9's in rear deck, (2) 12" square kickers in trunk, Sony 5500 head unit mounted in custom console.

You ever finish your project? Interested in how it turned out

Quote:

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Originally Posted by cdrod

If you're a purist who doesn't want to cut up his classic car, you can install a single 4x10 speaker that has 2 tweeters (L & R) in the factory dash location. RetroSound make a nice high powered, dual voice coil, 4x10 speaker that sounds pretty good although the tweeters are not that great and the stereo separation is poor because all the sound is coming from the center. It's definitely a compromised but you get some kind of stereo image up front without cutting up your car. If you have a factory AC car you will need to get a slim speaker (RetroSound has one R-410N) that will clear the center AC ducts behind the dash. I'm doing an install right now into a '72 Olds 442/Cutlass convertible that is using the RetroSound speaker in the factory location and 2 small 1/2" tweeters mounted in the dash at the A-pillars. The tweeters in the RetroSound center speaker have been disconnected so the tweeters at the A-pillars will handle the high frequencies to create better stereo separation and image. The tweeters will be mounted in the metal part of the dash forward of the dash pad so it's a pretty stealth install. One caveat is the windshield needs to be removed to drill the holes. I did sound check, test mock-up and it sounds better than I expected.

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How did this work out, divorcing the tweaters from the center dash location and putting them near the a-pillars? I've been thinking about something like that to get a stereo effect, but I'm not sure if it's worth the effort.

Great reply by the way. I know it's over a year old but I see you are still active on the forum so I hope you are willing to share your experience.

Clint:
My car has been a work in progress for many years, but it's currently in the body shop and should be painted in the next few weeks. That being said, I haven't actually installed my audio system to assess the benefits of the dash mounted "A-pillar" tweeters. I did a little testing with a 4-channel amp powering the center speaker and the tweeters just to check the wiring and polarity, etc., but without the windshield in place to reflect the sound it was not a good evaluation.

I can tell you that drilling the holes for the tweeters is not possible with the windshield installed. There is simply no way to get a drill with a hole saw into that space. I drilled the holes for the tweeters as close to the dash-windshield junction as possible so the sound reflection off the glass should appear to have a single source. I hope to have the car reassembled be the summer's end. I'll post an update when I have the audio system up and running.

Rodney

Thanks for the update Rodney! Congrats on getting her into the paint shop - that's a very exciting step. I'm working on my stereo install now and will see how it sounds first with the 2way speakers in the dash. I think on my Nova I can run wiring to the a-pillars easily and they are removable so I can modify to add tweeter pods if I decide to go that route. More than likely it will not be worth the effort for me, but I suspect it will help a lot with the stereo effect for you.