I have a sub with a mounting depth of 4 5/8 inch. This is probably a silly question, but is that from the outside edge of where the sub mounts? So, my box would be made out of 3/5=4 mdf and would have to be minimum 5.5 inches tall?

Thanks!

Dave

 

That is pretty close. Your thinking is correct. With 3/4 MDF the max depth for a 5.5" box would be 4 7/8". Which would technically just touch the MDF. Although 3/4 is just a bit less than 3/4 thick.

 

The more room you can have between the sub's magnet and the back panel of your enclosure, the better. Especially if have a high powered system and your sub has a vented pole piece(noticeable by a hole in the middle of the magnet). The purpose of this hole is to allow air to get to the voice coil for cooling. Pretty difficult to do with no room there. Experts recommend 3" clearance in high end home subs. That's not always feasible in car audio, but like I said, the more room, the better. People will say they have run subs with no clearance with no problems and that may be true. But this is can also a big reason for sub failure, overheating the voice coil to the point of damage or failure. And, in a lot of cases people think their sub just "blew", when actually the lack of a quality installation and their lack of knowledge is the culprit. Even very average subs don't just fail for no reason IF they are installed properly and used within their capabilities.

 

Thank for the info....I just wanted to know the minimum depth I had to work with. I am making a box to fit under the seats of my 05 Screw and will make it as deep as I can. I just need to figuire out how much room I need under it was well. Is it a problem if the sub grill touches the floor a little or should there be some room there as well?

Thanks
Dave

 

The sub grill can touch and not cause a problem. But, you do not want the subs surround, when it moves in and out, to touch. My first box from musicmoose, the subs surround was on the carpet and it sounded really bad. You could hear it hitting the carpet.

 

I have spikes under my boxes to give some clearance, plus they also "couple' the box to the floor, which helps bass response. They are actually made for home speakers. They are adjustable to a degree, which allows for some experimentation of the amount of clearance. Like dconder said, if your sub surround hits the carpet, it will sound like crap. You will also notice a difference in bass response by trying different clearances. But under the seat location doesn't allow much. I raised my seat about 3 1/2" in my '97 to make the room I needed for the set-up I wanted.

 

Although my sub sits behind the seats, it still applies here. I ran the risk of hitting the seat if I moved it back too far, so I put a grill over the sub to keep the surround from touching the seat. This would be a smart idea for a downfiring sub as well, just because the grill is designed so that the sub won't touch IT, therefore if the grill doesn't touch the ground, or barely does, your surround will be fine. Again, the more clearance both in front of the sub and behind it (inside the box), the better your sound will be.

For mine, I chose a deep mounting sub (Premier TS-W1500SPL, 6.4" mounting depth) and there isn't much room between the back of the box and the sub. The box itself has an outer depth of 8" and an inner depth therefore of 6.75". Not a lot left.
It's been in that particular box for a good 8 months now with no problems, sound quality is excellent.

 

Cool thanks guys. The sub I am getting has a grill that comes with it. I will mount that to make sure I have enough room and try to get as much extra as I can when I build the box.

Dave

 

Sounds good. Post some pictures as you go, or at least once you have the finished product! I'm curious to see how it works out.

 

I will! I am hooking my amp up and running the wires right now. I amtrying to get a really decent sound and figuire a sub is a must for it. My sub should be here by the end of the week and I already have the MDF to build the box. I hope to get the amp wiring done before the sub shows up, but with work and the weather things sometimes take longer than I plan them to be.

 

Awesome!

Amp wiring takes me about 5 - 6 hours depending on a few things in the vehicle and how well I hide the wires. This is also assuming I don't have to stop and go buy more stuff.. and how cold I am :P

As for the sub being a must.. yes. it is.
No matter how good your door speakers are, they still cannot hit those low low frequencies. Then you get higher excursion on the door speakers as they try, and your mid-high ranges suffer. Even a small 8" sub will make a world of difference if wired properly. It takes the stress of your other speakers.

Good luck!

 

I am sure once I get everything hooked up I will be hitting the forums up again for tuning info on my head unit. It is a Kenwood KDC-X689 and has more options for tuning different things than I can figuire out. I really want to get everything sounding as best I can with it.

Dave