everyone always says that it sounds bad to cross the subs over at a frequency like 200hz... but for some reason my PPI's sound fine...

I have to cut the kappa plates and the 6x9's at 200hz or I get too much vibration and the plates distort at high volumes... so putting the sub up to 200hz seemed to make the sound more natural... instead of 50hz... where I'd have no response from 50hz to 200hz....

 

You can't cross it around 100Hz? Are you sure it's at 200? Mine starts to sound like crap somewhere between 150-200.

After some more fiddling, it's official: the sub isn't able to pick up the frequencies I'm missing from the midbass. Set at about 150, I was getting a louder sound, but it didn't sound right at all (testing was at moderate volume - loud enough to hear, but nowhere near distortion). There has to be some monkey business going on, and I think my sub and amp are fine because some songs are absolutely beautiful - it's just a handful that sound crappy. It can't get worse with a new box.... I'm keeping it set at a tick above 100Hz, which seems to fill in nicely for most songs (mids HPF 100Hz).

LOL, I just realized that in my last post I wrote "my three choices" and then put four of them. I guess that last one really isn't one of the choices.
It's been a tough week!

 

if I pass my mids at 100hz, I get horrible vibration...

I even put liquid gasket behind my 6x9's the other day... I think the metal that the 6x9s are mounted to are the actual problem.

 

Try finding the bolts for that plate and tightening them a bit. That cut out annoying rattles. I'm either covering those plates with sound deadener, or making mdf baffles to put in there to improve the sound. I've already torn out the rubber in the plastic door vents - that made a huge difference.

 

yeah, I just pulled the actual vents... give you better bass response... in my opinion

I'm running into the problem where I can linterally pull the speaker out, and hold the speaker free-air style, and have MUCH BETTER bass response, than if I were to install it in the sail panels... because nothing aggrevates me more than 6x9 rattles... because normally the 6x9 rattles at relatively low volumes, and the sub can output much more bass at higher volumes before I get any vibrations whatsoever.

I think I'll dig around in there to see if I can't stop the rattles... man that liquid gasket stuff was a mess... and hard to get off my hands...

it didn't really help much... but maybe once I dampen the metal piece, I can get some decent bass...

these speakers are amazing at bass response... just from holding them in front of me and listening to them, I was impressed, and if I could get at least that much out of them in my firebird, I'd be happy...

it's really just the rattles that bother me... goddamned rattles...

 

I guess the question I'm asking now is this:

If you had a single 12", how would you design the box? I'm not necessarly going for style per se - more important are space-saving efficiency (including t-top storage) and sound quality. I do plan to carpet the top so it doesn't look like I found it on the corner (just giving you a hard time, Jim). It needs to satisfy the following criteria:

1. Fits entirely in the well - necessary for t-top storage.
2. Volume around 1.25ft^3
3. Easily removable
4. Good sound quality
5. No fiberglassing (this is only a bonus - I will do it if it makes a difference).
6. Amps mounted to top of box, still allowing for t-top storage.

Clearly, from my other posts, I'm leaning towards Disturbthepeace's design, which fits all my constraints (although the amps on top might not allow for t-top storage):
https://www.thirdgen.org/techbb2/sho...hreadid=146179

My other consideration is something like this top-mounted one by DSLDUDE2001:
https://www.thirdgen.org/techbb2/sho...s&pagenumber=3

There probably isn't enough room on this one to put both my amps on it. It also doesn't appear to be removable without taking off the rear plastic panel and using an oversized shoe horn.

Once again, I'm pretty much answering my own questions, but as always, opinions are welcome

Any other designs I should consider?

 

if you're using the "entire well," as you put it, you're gonna get more like 3.0 cuft, not 1.25...

then you'd want two 12" subwoofers, not just one.

 

Please learn how to read. I never said the box will take up the entire well. I said the box must fit entirely into the well. Bit of a difference....
The box will be a little smaller since it won't be fiberglassed into every nook and cranny, and it doesn't come up to the top of the hump over the gas tank. Since most of the volume of the well is up near the top, it explains how the box only takes up around 1.3ft^3 (and I bothered to do a little thing called MATH).

 

you said "1. Fits entirely in the well"... if something fits inside something... it is typically meant that it will take up as large as a space as possible, while still fitting in the given dimensions....

learn to clarify your vague descriptions.

 

Scrap, we need you to lay off the booze, just for a little while. hehe
If something fits entirely within a space, it means that parts of it don't prodrude outside the space - that is all. I even gave the approximate volume of the box, along with dimensions and pictures in the links. Those boxes clearly don't take up the entire well, and they only hold one sub. Even if you just looked at the pictures and didn't have a clue otherwise, you would have picked up on something... I also said that I want to be able to put both my amps on top of the box, so I clearly don't intend for the box to fill the entire well by itself. I believe I was quite clear, you just made an incorrect assumption. I'm sure you fit entirely within your car, but I wouldn't assume you take up the entire space. That's just silly.
Where do you come up with such an off-base comment? I wouldn't build a box that takes up 3 ft^3 for any sub on accident. Your statement about putting 2 12's in there is not the least bit helpful to me. The only random knowledge I have gained from that post is that someone could possibly fit a box in there at around 3ft^3.

 

from your post 04-30-2005 @ 03:33 PM... it sounded to me that this box was theoretical, and had not been constructed... you even ask, "If you had a single 12", how would you design the box?"...

For some reason all these pictures that you apparently posted, do not show up on my browser... that's wierd.

anyways, the only time you 'brush' on this... is here:
"It would also solve the problem of an ugly box that takes up an awkward amount of space - with a flat box deep in the well, I could at least put stuff on top of it if I had to and perhaps move my amps so I can store my t-tops again. Would there be any problems with the bass needing to escape through the small hole in the top mdf panel or around the sides of the box to reach the front of the car?" --- aside from the reference to those other box designs... and that's fine, but you are a tad vague when you say "T-top storage necessary," and "fits entirely in well...."... because you're right, it can mean ANYTHING... but pretty much 100% of the time when someone says their subwoofer box fits 'entirely' in the well... they mean its as big as the well... obviosly in your case, you mean something else... I'd just pick a tad different approach at describing it.

however, getting back to the topic....
Disturbthepeace's box looks ideal for you, that way you can mount BOTH amps on top of the box... and as long as there is an opening for air to travel to your ears... you will be fine, and also you get almost ZERO rattles when you have a shallow well-box, that is rear-firing...

I had a 10" orion xtr pro in a truck box that took up a good portion of my well, and when I faced it rearward, I'd swear it put out a deeper bass response than both of my 15"s...

 

The pictures are found in the links, not posted directly in the thread (I see no reason to post them twice). And you're right, I haven't built anything yet. No worries about the confusion

Good to hear that I shouldn't be getting many rattles. I'm guessing that you mean inside the car, because I've heard these orientations tend to rattle the sh*t out of the tail lights and license plate.

In fact, I just got an email from Disturbthepeace a little while ago.
Here's what he said about his box:

"The box sounded good with most rap and was very responsive with rock. Mudvayne sounded great as well as Korn and most other rock. Never really listened to country but when I did I had no complaints. I hit a 148 dB with an eclipse in the box and the Eclipse was pretty deep so I would imagine that your JL would fit as well. I listen to everything from eminem to dre to bone crusher to tech n9ne to mudvayne to lamb of *** to korn to oasis to incubus to lonestar to chris kagle to everything else under the sun. I was happy with it and i think u would be to. Let me see some pics when ur done if you decide to build one."

Has anyone gone with a down-firing sub? I like the way mine sounds for my home theater, but it seems like a strange application for the well, since the box would probably cut off the path from the speaker cone to the cabin.

 

the main problem with down-firing, is the sound wave is pretty much just leaving the vehicle... its going down to the ground/bottomofwell, and then coming back up...

you'd be better off reflecting off the glass in that case.

 

That's what I was thinking. Unless you concrete the bottom of the well to give an excellent reflective surface, it seems like more sound will leave the car than will reach the listening area.

 

I also feel that on a hatch-reflection setup, you lose a lot of bass on the hatch vibrating... you have to have a perfectly tight hatch, and all plastic panels, otherwise you'll not only lose your bass output becuase the hatch is converting it into motion... but you also just have annoying plastic rattles... which I seemed to be able to turn up the volume/bass a lot more when I had a rear-firing box, with little or no rattles, (in the car)..

as a side note, I still get mad vibrations on my tail lights and license plate... I need to go in and replace those plastic wingnuts with something made out of metal, so I can tighten that stuff up somethin' fierce.

 

Facing the subs down will work fine as long as there is adequate space for the sound to get into the cabin. I've heard setups with them facing straight down and they work fine.

BTW, I looked for those pics I mentioned above, but I can't find them. Hopefully I've got backups on my father's computer.

 

Just buy a gallon of Second Skin Spectrum to paint in the well and the back of the hatch and you'll be golden. If you use a little more than a gallon, you can cover the spare tire area and behind the lock box. Nothing outside the car vibrates now and it's so quiet, except for the places where my t-tops don't seal (must be the same place the water sneaks through).

I decided not to build the box afterall since it will not allow clearance for the t-tops, at least not with the amps mounted on top. The only other option is if I can find another out-of-the-way spot, which isn't looking so good right now. I saw one mounted in the back seat, but it doesn't look like it gets enough air to stay cool - maybe if I put a couple small fans back there....

 

okay, some things to think about...

1- can you not store the t-tops OVER the amps and subs, (you have speaker grilles, right?)

2- is there SOME way to safely store the t-tops behind the back seats? possibly requiring alteration of the back seat?

I just strap mine over the sub box and amp... works great so far...

 

I was thinking of hollowing out the back seats to accomodate the t-tops - that would be pretty sweet if people could still sit back there. BUT, since that would require a lot more work and there is rarely anyone sitting back there (and it's not at all fun to sit back there with the t-tops off), I'm sure I could just fold the back seat down and create a way to attach the leather carrying bag since it already has adjustable straps. Either way, I could put the stereo equipment in the well and not care how tall it is.