Contour Enthusiasts Group Archives Forums Modifications Audio Rear Deck free-air Sub question.

The idea of an 8" free air sub in my rear deck appeals to me, as I don't want to spend a fortune on a big woofer and box, and I don't need a lot of bass... just some to fill out the sound.

I don't own a jigsaw, nor do I know anyone who does. Would it be possible to just drill some holes in the rear deck where the cut-out is to let the sound get in? I figure a whole bunch of small (1/8" or 1/4") holes would almost substitute for a speaker grille anyway.

Do ya'll think this might work?

Thanks for any comments. If you tell me the idea sucks, I will not be offended! Unless Honkey Tonk tells me it sucks, then I'll be deeply disturbed.

Brian

There is someone on the list who has a free air 8" sub in that location, and he is quite happy with it. I don't recall what brand...
he actually cut out the rear deck and mounted a grille over the sub instead. It looked pretty good actually. The grille color matched the interior.

APT CSVT and cthomp21 both are using 8" free air subs. Both seem reasonably happy with them. They won't be hitting 140 dB with them or anything like that but they are competent at reproducing sub bass. If you want just something to fill in the bottom end of your system, they are a very good option.

Brian, the reason why I used an MDF adapter was becuase the driver I used has a pretty decent Xmax for an 8" (8.7mm, IIRC). I didn't want it to hit the metal of the deck as that would cause some seriously bad noises. I left the carpet of the deck in place, but cut away the cardboard-like material under it which is the real sound blocker. Cthomp21 didn't do this at first and said it sucked. Ened up disconnecting it for a while. Then he cut away the insulation above just the speaker (I think he left the carpet also) and it made a world of diffrerence.

Jeff's right, there is another user that cut it all away and put a speaker grill there. I cannot remmeber who, though. I was going for the stealthy factor.

I highly recommend the MDF adapter. If no one can help you out, I could probably cut a piece for you and ship it. I'm sure I have some scraps around to work with. Just pay for shipping.

You said you have a drill, right?

Most people are completley against free air systems. But, I've heard of many cases where it's worked out very well. It certianly is'nt ideal, but I can still put 4 suitcases and a toolbox in my trunk for 1500 mile trips without losing my bass. I think in the worst case, the driver will wear out sooner. Maybe 4-5 years instead of 10. That's fine with my as it was only $50 and could be cheaper next time.

Aaron

Yep, I did leave the carpeting in place. I just trimmed out all of the cardboard backing to make it as acoustically transpearant as possible.

I also used some 3/4" felt carpet padding between the metal of the rear deck and the rear deck cover. It made a world of difference, completely eliminated all of the rattles.

I'm planning on putting another 8" sub in the rear deck on the other side in the same configuration for a little more bass.

Just not enough time and too many different projects going on right now.

In any case, cutting/drilling holes in the rear deck is unnecessary. Just use some 3/4" MDF to bottom mount the speaker, trim out the rear deck cover, and use some rattle-preventing insulation. It'll definately fill the goals you're describing.

Hey Guys,

Thanks for the replies.

I dont' know that I worded my question right.

I would of course use a spacer of some sort because I know that the woofer would likely hit the deck if it was mounted directly.

However, my question was just based on the idea of not removing an entire section of my rear deck, but just drill holes in it instead.

Would that work?

Again, you all rock. Thanks.

Brian

I don't understand. The only part of the rear deck I removed was the cardboard backing on the carpet. This was done by my brother lying in the trunk with an Exacto knife. You don't have to remove the metal of the deck itself nor the carpeted cover. However, you do have to emove the cover from the cabin side if you want to add some insulation there. I haven't done that yet but need to. I've got carpet pad lying around and haveno excuse why I haven't stopped my rattle yet.

So, where would you drill these holes? In the metal or the carpet or the cardboard?

I THink i am confugled too...

Are you telling me that in your contique the hole was already cut out in the rear deck? Mine isn't. I would have to use a jigsaw to remove the 6" diameter section in order to get any sound through.

I figured I"d drill into the plate instead of removing it in order to create a passage for the air to get through.

Brian

Ahh, yes, there is a measured 6.5" diameter hole in just the metal package tray on the right side when bending over and looking from the trunk side in my car. I asked a co-worker with a 99 Mistique and he has it as well. Seems odd that you would not have it.

But, if you really do not, I recommend cutting a hole large enough to directly mount your driver. That way, no MDF adapter.

Or, possibly you can just use an adapter and don't cut any holes in the metal. It is bass and shouldn't reflect the frequencies it'll get.

Any thought's Dave?

you need to get yourself a bucket, a thick piece of cardboard and a sparkomatic 12" woofer....

j/k

let me think about some possibilities and get back with you.