Custom Box = Epic Fail

[skylinedrifter]

Several weeks worth of work has yielded a subwoofer box that completely sucks. In fact, I am reasonably certain that I have made the audio gods weep. But, I have learned a few things which should come in handy for box 2.0. such as making certain that the next box is sealed, offsetting the speaker hole and using measurements that take moving seat parts into account.With the Audio Gods as my witnesses, I will redeem myself! lol.

[damronjr]

Are we going to see 1.0?

[NibCrom]

Don't we get pics of your fail?

[Sublimewind]

Agreed, we need pics of the fail... So we can devise ways to return to the path of WIN.. What went so wrong, how was the construction done... WHY is it a fail...

[Toasted7]

We want pics so that we can assist to help you make 2.0 a success!

[skylinedrifter]

I have some pics but not on this PC. Here is an illustration, tho.The speaker fit underneath the seat while the angled area provided extra volume as well as a comfy place for passengers to place their legs.

[Sublimewind]

Yeah, so what went wrong with construction???

[RePo]

The sub woofer mfg will have a recommended box volume in cubic feet. There should be a narrow acceptible range for ported (larger volume), and sealed (smaller box). Do you know the range (or the speaker model so we can look it up)? That will be the first thing that comes to mind when calculating the next box build. If your current box is about 1.0x cubic feet, it might just need the port deleted.

[B14CK_H4WK]

just keep your custom box sealed it will sounds fine and the life of the sub will last longer

[skylinedrifter]

Yeah. That was my biggest problem is that I designed it to be ported. I plugged the port and it sounded better, but still not good. I reckon that part of the problem is the flat area behind the speaker reflecting sound right back to it. Box 2.0 is going to be a similar construction except the speaker will either be angled or there will be some material inside to deflect sound.

[wyatt89]

If you have never designed speakers before, ports are not a good thing to try the first time...do you have winISD?

[skylinedrifter]

I don't... but I will when I get home.

[Sublimewind]

Quote, originally posted by Sublimewind »Yeah, so what went wrong with construction??? Once AGAIN, what went WRONG.... Can't help if you don't answer...

[Sublimewind]

Quote, originally posted by skylinedrifter »Yeah. That was my biggest problem is that I designed it to be ported. I plugged the port and it sounded better, but still not good. I reckon that part of the problem is the flat area behind the speaker reflecting sound right back to it. Box 2.0 is going to be a similar construction except the speaker will either be angled or there will be some material inside to deflect sound.If you designed it to be ported, it WILL be to big for a decent sealed box... Ported designesd are "typically" 2/3's larger than a sealed box, just off the top of my head.. but usually If I see a sub that requires .5cf net, the ported counterpart will be ~1.5cf net.. And I want to know WHY you think that the reflection off the back wall is causing a specific problem... there are literly hundreds of thousands of boxes running around with parallel walls... now, this isn't ideal, but it works (Ideal being a sphere made of cement )How far was the sub from the back wall? You want at least 1/2- /4" for the pole vent to breath.. You need to have a look here.. http://www.bcae1.com/ ... On the right, scroll down to topic 110.lastly, WHAT SUB are you using?

[skylinedrifter]

Sorry, bro. Didn't mean to ignore your question.Sub: Pioneer Shallow Mount TS-SW251Minimal sealed volume: .5 cfMy volume: .7 cfFirst mistake: Innacruate measurements led to me needing to build, mock, disassemble, re-cut, re-assemble and so forth several times over. Now I have the correct measurements so this won't be a problem.Second mistake: I designed the box to contain slightly more than the minimum volume for a sealed box. At the time, I didn't realize that there needed to be a volume difference and only made that discovery after most of the construction was finished and the box was already glued & screwed. I plugged the port as best as i could and this dramatically improved the sound.Third Mistake: I really think there is some interference from the soundwaves bouncing off the back of the box. The speaker seems to be working way too hard and I am getting minimal sound for what looks like a whole lot of effort. The sound I do get seems way too distorted. Regardless of whether or not this is actually the case, I am not going to take the chance and box 2.0 will have an angle designed to help reflect the sound deeper into the box. As it stands, the speaker almost rests on the back of the box.

[Sublimewind]

Well, you do need some breathing room behind the woofer, but only 1/2-3/4" and you really don't have to worry about the backwave "that" much... When making your measurements, just make sure you include/exclude the 1 1/2" depenings on if you use 3/4" MDF, but I can' tell you right now, for that small of a box, you CAN get away with 1/2" MDF... If need be, add a brace that bridges between the front and back wall, to stiffen it up... I'm not sure I follow the "third" mistake? I personally have built boxes with parallel walls and had no issues.. I'm wondering if you got it sealed properly... Oh, and I wouldn't be expecting HUGE bass from a thin mount sub, they simply can't do it as well as tier "normal" counterparts.. They make bass, but never as much as the same regular sub will...FYI... Keep us informed.. good luck with 2.0

[wyatt89]

Quote, originally posted by Sublimewind »Oh, and I wouldn't be expecting HUGE bass from a thin mount sub, they simply can't do it as well as tier "normal" counterparts.. They make bass, but never as much as the same regular sub will...FYI... Agreed on that one You most likely wont have the amont of space necessary to make a good sounding ported box under the seat...If you put one under both the driver's and passenger's seats you could get some thump going but I honestly have no idea what is under the driver's side seat...I've got a 6 disk under my passenger though.Make sure you seal everything with caulk, liquid nails, silicone, resin, or whatever else you deem useful because if your sealed box has any leaks in it it's not going to sound right...In my experience with building cabinets, you shouldn't need screws or nails if you have built it right