Enclosure advice
hey guy's, i recently swapped from 2 x Velocity 10's to a single 15 inch Soundtream SPL sub, which i fitted to a sealed Beva Enclosure. Recently the box has broken collapsed around the outside of the sub, and in a few other places. Now i've searched the net, but the sub is an older model, so i cant find any spec's for it's ideal enclosure. So short of actually contacting soundstream, i was wondering if anyone knew some rough specs i could follow to create an optimum enclosure for it. I've always wanted to build my own enclosure, so i figure it's about time i gave it a go a go. I would also like to go for a ported enclosure this time around to. The previous box was made from 12mm MDF, should i go a little thicker?. I'm willing to sacrifice any and all sound quality to achieve maxuimum bass and SPL. I know that might sound a little odd, but i just removed a SQ system, and i'm merely just playing around and expereminting and having a bit of fun hitting those low notes
If you're building a ported enclosure, you need the EXACT specs or it won't work as designed.
Use 18mm minimum for sub boxes.
What's the model number of the sub?
These are the recommended ported/vented boxes for the SPL15 model subwoofer.
The full manual can be found here. The manual has the T/S parameters for you to design a proper SPL box.
Thanks mate, i'll have a read through it, i must suck at searching on the net!!
Yeah, 2nd page of results in Google when searching for "soundstream SPL15"
what would happen if i was to build a box larger than thier reccomended dimensions? And what size MDF is the best, cause the 12mm broke last time..
I already told you to use 18mm MDF minimum
If you make the box larger, it changes the tuning frequency (lowers it) and frequency response.
Sorry dude i missed your post about the MDF and ports, i scrolled straight past it-
Ok so i looked at the chart for the box dimesnions, and i couldnt make much of it, it says, either 2,3, or 4 foot (3) enclosure, i coulnd;t figure out the dimensions for a 4 foot (30hz) enclosure. Assuming that it would be quite large, i went to bunnings and had them cut up some 18mm MDF. So the box will be 900L x 500W x 500H. I'll put it together and see how it goes i guess. I'll have to pop into jaycar aswell and pick up some ports.
Jaycar ports will most likely be the wrong length. Use PVC pipe offcuts from a plumbing store.
900mm x 500mm x 500mm is 8 cubic foot... Double what you need. If you're going to do this, you need to do it properly or it's going to sound shit.
A 4 cubic foot box is 113268 cubic cm or 113.268 Litres.
Calais_Rattling....
n jaycar dont have any ports with decent bends, i jst got 3 of their 90mm adjustable ports cut em all up so i get a nice 90deg bend, then coated it in sum 100mile tape.
Shoulda just got a heat gun, done it right istead of muckin around with prefab
How can i do it properly, or should i just go get the MDF re-cut before i start? its not a problem getting it re-cut cause i have to go back down there anywhere, because when i measued it, i forgot about overhang, so i have to take 40mm off both the side pieces so the top and bottom with will line upOriginally Posted by StoneX
By "do it properly" I mean you need to work out what size box will be 4cubic feet in volume and then get the wood cut to size. Remember that the internal volume is what matters.
You need to draw up the box and then do the math to find out what dimension timber you need. If you can't do L x W x H = Volume, you might need to get someone else to design it for you.
I thought you were saying i could do it with those dimensions. Well i made a box anyway, so i'll just see how it goes i guess. It's slightly larger internally than the sealed box the sub was originally in. I'm hoping it will atleast perform better, seeing as it's 6mm thicker , will be ported, silicone sealed, and dampened. As far as ports go, how far should they need to extend into the box?
Last edited by HCVP; 11-05-2009 at 03:44 PM.
Tell us the internal dimensions
ok, dunno if this helps, from the front of the box, it's 435mm deep, so to the back wall. By 460mm high, ad 430 mm wide. Thats measured internally with a tape measure....I'm probably wasting my time, but hey i gotta start somewhere, and atleast if this enclosure doesnt work, well then i've at least built one, and have a much better idea of what i'm doing next time around
43.5cm x 46cm x 43cm = 86043cm^3 = 3.04ft^3
You'll need to use the ports recommended for the 3ft^3 box... Three 4" wide x 13" long ports.
I've never noticed on a sub box before ore than one port. If im putting 3 ports in, will it matter where they go? Stone X do you think the enclosure will turn out okay. Also i didnt screw it together, cause i dont have a drill instead i glued it and put a nail like every cm across?
If those dimensions are right and you use the right size ports, it should sound fine. You'll have pretty much nailed Soundstreams recomended size and tuning.
What type of glue did you use? Typical wood glue or liquid nails work well.
Ok, i come up with a list of questions, than i am unsure of the answers to. I've read quite a bit on the net, and now i know a lot more than i did when i started, but i still obviously have a loooooong way to go!
1- Does it matter where i put the ports on a box, in relation to where the sub is mounted
2- How does the positioning of the sub in the boot, and the direction it fires affect it's SPL levels
3-If maxuimum SPL is the target, should the inside of the box be dampened.
4-Can the use of Polyfill on a Ported enclosure, increase volume levels
5 With my Head Unit, i have some options with the Sub settings, 30,50,60,80,and 120hz. And also normal and rev- The best i could get out of it before, was set at 80hz, in rev mode...But adjusting the HZ setting, had almost no affect on the sound at all.
6-In full pass mode on my amp, there is a tuning adjustment for the HZ, which goes as low as 30hz, or should it just be run on LPF? I realise it's a lot of questions, so thank you heaps to anyone that can answer even just one of them. And also a big thank you to Stone X and Calais Cruzin for your help with this so far.
Custom Car Stereo Systems
1. Ideally you want to mount the ports on the same side as the subs, although not overly important.
2. In most sedans, sub box at the rear and facing towards the tailgate is usually the loudest....although not the most practical spot
3. No, for maximum SPL you wanna build the box as strong as possible, inside the box should be coated with fibreglass resin (firstly to aid in strength and secondly to aid in air movement as the resin is smoother than MDF)
4.No
5. The LPF setting in your head-unit is basically the same as a LPF on your amp, only digital. Maybe the filter on the amp was set to 80hz and turning the head-units filter above this wouldnt make a difference as the amp is filtering at 80hz anyway.
6. LPF would be the ideal filter but i will admit im not too familiar with the full pass mode.
Hope this helps.
150db in a commodore =
Thanks that helps a lot. Ive never had any experience with fiberglass before, is it a difficult task. I'll do some research on it tonight and see what i come up with. Will the current dimesnions of the box still be alright by the time the ports and resin go in? From everything i've read on the interent, it says ported enclosures are gererally larger than sealed ones. From what i can see with the one i'm building it's actually a little smaller, but being a different shape i know it could be larger internally..If the sub is going to face the rear towards the tailgate, does the sub require a minimuim distance between itself and another object e.g the tailgate for optimum performance?
Last edited by HCVP; 11-05-2009 at 03:44 PM.
Custom Car Stereo Systems
Fibreglassing the inside of the box isnt a hard task.....just get yourself some resin, mix it up with the catalyst then paint it on the inside of the box, just like paint itself.
Another little secret is to eliminate all right angles inside the box by either pouring resin into each corner while the box is sitting on an edge so it forms a 45 degree angle, or buy some 45 degree angle wood strips and screw/glue them into the corners. See attached pic. (i used modelling clay for where the corners meet, the smoother the better)
Whats the outside dimensions of the new box, and wood thickness?
I'll let you know its internal volume.
For rear loading, anywhere around 6-10" from the tailights is the way to go, you'll have to get on a spl meter to test the optimum clearance though.
150db in a commodore =
It's 18mm, 460 x 440 x 500, Stone X did some calculations earlier and came up with 3.04ft^3 When apllying the resin, is it true i shouldn't apply it to the baffle board? And should i resin it before, or after i've made my port holes?
Last edited by HCVP; 26-04-2009 at 01:00 PM.
Posting Permissions
LinkBack URL
About LinkBacks
Reply With Quote