Pics of my DIY sub box

[tsbrewers]

Pics of my box I made. I don't have it installed yet, still trying to decide what subs to throw in there.

http://imagep.webphotos.iwon.com//1000027187/1000027187_372002112808AM0.2842981.jpg

http://imagep.webphotos.iwon.com//1000027187/1000027187_372002112824AM0.6664392.jpg

I will have installed pics later.

Brew

[ibthumpin]

Looks good man!:thumbup: And with that little storage cubby, you have a place to put all those potatoes or apples or whatever they are..................:D

What's it gonna hold 10's or 12's?

[tsbrewers]

Well, the cubby is for the amp, but I figured I would get asked about those things in the background. It is about 300 stuffed pumpkins. My Finace and her parents are big crafters so we always have stuff like that laying around the house. :(

It will fit either, I ended up with .85cu3 of air space, so I have found a couple tens and a couple twelves that would be fine in that space, but I am not sure my 350wattx1 amp will push two twelves.

Brew

[tsbrewers]

Just an addition, this thing better be worth it, cuz I broke my little toe on it today, seriously. the toe is the size of a wattermelon and the whole rest of my foot is deep blue. I guess I know it is solid though! at least more than my toe is. :)

Brew

[TribalVision]

even though your going to use a small amp, you might want to vent that compartment. couple holes in the back should do.... but it's a good looking box. I'd personally look into a small class D amp, and a set of 12's. say maybe a JBL 600.1 and a set of IDQ's. 300 per sub would be nice.

JMHO

[tsbrewers]

Please, before you reply, at least read the last 2 paragraphs. :(

Well, I already have the amp and I am sticking with the amp. :) Seriously, if it comes down to not having enough power, I will live without subs. I am not a big music freak, this is an example. My last truck had a 10 disk cd changer in it when I bought it, the day I bought it, I put 10 cd's in it. The day I sold it, -four years later, it had the same 10 disks in it, and I couldn't name 5 of them.

I am a carpenter and did some work for a local guy that own's a car shop here in town. We traded my labor for credit at his store. So a couple years ago I got the amp, HU, some speakers, etc. But my last truck wasn't worth the time to install them. So they have been sitting in my shed for a couple years. Well, now I have a little better ride, I decided to put them in. I don't need a huge system, just a little better than stock. I have a total of about $50 invested as we speak, and don't want to spend a whole lot more.

Ok, what is the difference between ported and sealed? I know the physical difference, but what would make one better/worse than the other? From what I know about them, a ported is slightly more efficient and can go a few hz lower? Am I on the right track?

I don't mean to be pissy at all, but I have posted this on probably 4 pure car audio sites, and even though I have gotten many responses, no one seems to be reading my questions. They see "I need a good 10 sub....." and they start firing away. Get this, or Get that, or Get these subs and this amp. They don't read that I have an amp already with limited power, what size my box is, or anything. I appreciate the help from everyone, but I am not getting anywhere. I have spent literally 15 hours on this discussion and have not gotten anywhere. :cussing:

MY MAIN QUESTION- I have narrowed it down to the Image Dinamics subs. The IDQ10's or IDQ12's. Now the problems, I have .85cu'3 and these tens are best in a .25 to .50cu'3. The twelves would be perfect in my box, they require .75 to 1.0 cu'3. SO my big question is, will my amp be ok for the 12's? or Should I get the tens and try to make the box slightly smaller?? The tens would be ok if I ported the box, thus my question above, should I port or what?? ??????? These subs will never be over 100db, so will my amp cut it???


Brew

[TR02Yukon]

Over simplified generalization regarding ports:
Ports have the advantage of making some of that energy that's being radiated from behind the driver available though the port. Sealed obviously can't do that.

Here's a better read:
Ported
http://www.diysubwoofers.org/prt/

Sealed
http://www.diysubwoofers.org/sld/

or here:
http://www.landfield.com/faqs/car-audio/part3/

I like properly tuned ported subs as you almost get the output of two drivers(around tuning point) while only using one! When I say properly that's with a large enough port and low enough tuning that it closely resembles a sealed subs response.

___________

" Now the problems, I have .85cu'3 and these tens are best in a .25 to .50cu'3. The twelves would be perfect in my box, they require .75 to 1.0 cu'3."

Please keep in mind, recommended box size means crap. In reality it is almost always advisable to go bigger than recommended as you'll lower the subs overall Q which will lead to better transients or "faster", "Cleaner" bass. Almost every SQ competitor wouldn't even think of using a suggested box size. I'd go with the 2 10's using your speaker choices.

I wouldn't attempt to port that small of a box using a 12". In order for the vent mach(wind noise known as chuffing when wind is pushed through the port at high volumes) low enough you need at least a 3.5" port that would need to be 39" long if tuned to a low 27hz!

If you use 10" a port that is 3" in diameter and 28" long would work nicely although I think you may not have the room. Going shorter just raises the tuning which can result in a boomy sub or crappy SQ when the sub unloads because it's trying to play a frequency lower than its tuning point. If you want ported the lowest I'd tune is 30hz which would need a 3" port @ 22" long.
_____________________



" SO my big question is, will my amp be ok for the 12's? or Should I get the tens and try to make the box slightly smaller?? The tens would be ok if I ported the box, thus my question above, should I port or what?? ??????? These subs will never be over 100db, so will my amp cut it??? "

In most instances 175W per sub is more than enough and especially in your case with those drivers and saying you're not after bone crushing bass. Heck, with 2 10's and 175W each you ARE in for some killer bass either way, just not the insane levels some are used to.

Hope this helps?

[tsbrewers]

Yup, anything in plain english right now helps. I am just a little frustrated. But you saying that 175 apiece should be enough-really helps the most. I wasn't sure if I was wasting my time or not. No one else would come out and say either way. So thanks, I needed that. :)

Brew

[tsbrewers]

Thanks TR02Yukon, I will probably just go with these tens and try it sealed. If worse case, I can put some blocks in or something to decrease the air space. Thanks much for your help.

Brew

[TR02Yukon]

I think you might have misunderstood? There won't be any need to decrease space, bugger is "almost" always better. By going bigger you lower the overall Q of the sub which ultimately gives better sound.

Manufacturers just pick a design that is rather small(to accommodate the masses) and yields decent sound. If a person says you need to follow the manufactures spec'd box size to get the best sound they don't know a lot about subs. You can trust me on this one for sure.

[tsbrewers]

Ok, I was planning on just giving it a shot, then if it needed it, I would decrease the size. But if I am going to be fine with this size, all the better. :) I am really looking forward to getting them in my truck, and appreciate the help you have given.

Brew

[HENRY]

To add a little,
Choose the woofer with the best efficiency.
In my opinion, the amp you have will do fine, and since you wont have a better amp to compare it to, you really wont know the difference.

Not only would a larger amp give you "slightly" more sound, but i think whats more important is that a larger amp usually yields better sound through more control of the driver.

Remember, to get even 3 db louder you need TWICE the amplifier power.

[tsbrewers]

Ya, if I had the money or I guess more importantly the space I would love to the the DEI 1100, (imagine that, DEI again, :) ) But I don't and I can't so i won't. Seriously though, as long as I can get a little base I can feel, I will be ok. Worse case, I will just unplug one of the subs, and feed the other the whole 350 so I think it will all work out ok.

Brew

[TR02Yukon]

To add to Henry's statement, here is a break down on amplifier power and how it relates to sensitivity and output levels.

Say you have a sub with a not so great Sensitivity rating of 85db.

Here is the wattage needed for the volume levels attained. (as long as sub is capable)
85db=1W
88db=2W
91db=4W
94db=8W
97db=16W
100db=32W
103db=64W
106db=128W
109db=256W
112db=512W
115db=1024W
118db=2048W
121db=4096W

Now a new driver with a 89db sensitivity:
89db=1W
92db=2W
95db=4W
98db=8W
101db=16W
104db=32W
107db=64W
110db=128W
113db=256W
116db=512W
119db=1024
122db=2048


Since TSB said he doesn't plan to run more than 100db he is more than safe with 175W even with the least sensitive speakers he can find. Even then they will still pound by many peoples standards. I'm willing to bet he comes away from this astonished at the bass his truck is capable of and realizing he was worried about absolutely nothing. Even though I run way more than 175W to my sub I believe 175W per driver is still a lot of power, many happy owners of subs out there being run with less.

Also keep in mind that the small cabin of a car usually adds anywhere between 5-12db of sensitivity(depending on size of cabin) compared to a much larger anechoic chamber where speakers are usually spec'd at. This is why its so easy to attain way in excess of 120db measurements in a car while only using as little as 250W to 500W's.

[BC Rod and Custom]

i'd got with 2 infinty kappa 100.3 se 10's i've got one in my truck in a .66 cu. box with 130 watts to it and it thumps. just put it in yesterday and i'm very happy with the whole sound of my system.

:edit:

you can get them for 85 a piece at www.ikesound.com

[HENRY]

Forgot to mention that if you wanted a bit more volume, you could always port the box.

It would be a bit more boomy, but could yield a little more sound.

[redsierra]

I just have a Reference Series 8 inch powered Bazooka sub in my 00 GMC. It is ok, but I have been wanting to build myself a sub box for under the back seat similar to Tsbrewer's. Looks like you did a great job. I am very handy but would like to have some plans or dimensions (handy but not creative).

Once you find out how twell your enclosure works, would you be able to either post or email me some plans?


Again, Tsbrewer, good job!

[tsbrewers]

Well, I can give you some rough dimensions, but probably not a whole lot better than that. The problem was, my amp is fairly large being a 5 channel one, so I actually made the center section to fit the amp, then made the boxes as big as I could. I could have gone larger if I would have made the box go up and over the hump where the jack is (was, it is now under the hood) but once I did some figuring and found that I could almost get 1.00cu' a box with out, (figuring putting some fiberfill in, which I am not going to now) I just basically made them square. Plus I needed some room behind the box for the cap and stuff.

I will help out as much as I can. I am a carpenter for my day job, so it is one of those things, I do a lot of and couldn't really explain it. I just took the wood, scribed it, cut it, measured the next, ripped it, glued and nailed it, etc. Not really taking my time, but it turned out ok.

But to be completely honest with you, if my amp weren't as big as it is, I would have gone with a prefab, like the mtx thunderform. They are about $250 shipped from Ebay, sell the two subs that it comes with for $100 or maybe more, so for $150 you get a nice color matched one, that has a ton more space, giving you more options for the subs. So IMHO, figuring in the 3 or 4 hours to build. $20 for wood, same for carpet and glue, I am not sure it is worth the time. But it is cheaper if you don't figure in your time. I am not trying to talk you out of it, just giving you my thoughts behind making mine. feel free to ask any questions if you decide to build, I will help as much as I can. You can email me when you start, and I will take a buch of picks, do as much measuring as I can, that kind of stuff to help you out.

Brew

[tsbrewers]

I thought about porting the box, but I don't have the room for the specs on the Sub's page. They say a 3" id port 15" long for 30hz. My longest inside dimension is 16", so the port would have to be elbowed or something. I will give it a shot leaving it sealed, it has to sound better than no base at all.

Brew