HD3 box designs.

[SPL140.2 5,000+ posts]

.23 is the woofer displacement, my advice is to listen to DJ he knows what hes doing //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif If he says a 12 is optimum for your space use it BTW a 12" can be just as loud as a 15" //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[Jeremiah25 10+ year member]

ho is that??......not me right?

no he wasn't talking about you

 

[Jeremiah25 10+ year member]

Typically speaking firing the sub up is not a good idea in a trunk car. That's the point DJ was trying to get across. In general, because you are using a trunk car, you would be better off with a smaller sub firing to the front or rear of the car than you would with the larger sub firing up.

I've done quite a bit of testing with the HD3 12 -vs- the HD3 15, and with a properly designed box there is very little difference in SPL. Firing the sub in the wrong direction will yeild a much larger loss in SPL than going from a 15 down to a 12. On the other hand from what you have said so far, it sounds to me like you have room to fire the 15 to the front or rear.

 

[cha0 10+ year member]

Just wow. . . . . . . MAKE UP YOUR MIND. I'm only going to say this once.
The recommended enclosure is 4.5 cubes @ 40hz. That size and tuning is RIGHT on the dot. It doesn't need to be smaller or larger, period.

40hz tuning gives the best blend of SPL and SQ. Tune lower and you don't really gain anything. Every note gets quieter and it's not worth the trade off for low end extension you'll never hear. LOL @ the people who say otherwise.

This is a plan for a 4.5 cube after displacement box using external 4" aeroports. There are only 3 holes pictured because that's what I planned on doing. I put 4 ports on instead now. Use this calculator to calculate your tuning

You have everything you need here.

yea i have that the only problem is the specs of my trunk. i have a depth of 32 inches, a width of 44 inches and a height of 12 inches.

i dont have the knowlege to adapt the box you posted to match the specs of my trunk...

 

[prochobo 10+ year member]

Dang I read wrong. Go with the 12"s for christ sakes. You DO NOT want to fire any way except for forward or rear.

 

[jeremiah 10+ year member]

Dang I read wrong. Go with the 12"s for christ sakes. You DO NOT want to fire any way except for forward or rear.

the car is 44 W/32 D/12 H you cant do a 12" sub

 

[jeremiah 10+ year member]

dos the HD3 com in a 10" if so two 10" DH3's>>one 15" DH3

 

[jeremiah 10+ year member]

.23 is the woofer displacement, my advice is to listen to DJ he knows what hes doing //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif If he says a 12 is optimum for your space use it BTW a 12" can be just as loud as a 15" //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

OK:yumyum: ...what is the driver dis of the 12" and 10" //content.invisioncic.com/y282845/emoticons/yumyum.gif.0556df42231b304b9c995aefd13928a8.gif

 

[prochobo 10+ year member]

the car is 44 W/32 D/12 H you cant do a 12" sub

OK //content.invisioncic.com/y282845/emoticons/rolleyes.gif.c1fef805e9d1464d377451cd5bc18bfb.gif

So what size sub is in there right now? stfu kthnxbye

To the OP, now that I look at the picture of your trunk again, you can possibly fit a 15" firing fowards/backwards. All you needa do is make the box long so that it doesn't hit the rear deck. That way you can retain your 17" of height. The only problem is airspace. Measure that area in your trunk before you hit the 12" height barrier and if it comes out to over 4 cubes, then you're good.

 

[DJL 10+ year member]

This is a copy of my last e-mail to chaO:

"Mike: If you would read over my e-mails and answer the specific questions I asked of you regarding specific dimensions and amp power your box design would have been resolved with the exception of the 8 cubic feet net size which is far to large to get any decent sound quality. SPL would depend to a large amount on amp power and loading of the port and sub which I am trying to find the best solution. I am trying to get away from having to squeeze the the sub up under the back seat deck area.

I believe we can find room to fire a HD315 upward but I need the dimensions I have to work with. If you could provide the INTERIOR dimensions of the "divit" it would help. I asked for the dimensions of the box pictured (which you did not provide) to determine just how much space was available in that area.

I can't really help you if you don't provide the information I need. It is a simple matter to design a box of 8 cubes and fire the sub up; no problem. Would it do what you want it to do; no it wouldn't. Would it make our sub and box design fuction to its optimum; no it would not. Would I design such a box; no I would not.

I also need the distance between the floor of the "divit" area and the bottom of the trunk lid."

For some reason Mike is hung up on the 12" box height and huge box when neither is necessary. I really would like to help him out but I can only do so much.

 

[prochobo 10+ year member]

Yeah, I know what you mean. I'm pretty sure he can fit a 15" firing forward/backward in 4.5ft3 as well if he makes the box extend the length of the trunk towards the back.

 

[DJL 10+ year member]

I don't think that would be a problem and would be the best solution but he wants the sub to fire up.

 

[cha0 10+ year member]

.23 is the woofer displacement, my advice is to listen to DJ he knows what hes doing //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif If he says a 12 is optimum for your space use it BTW a 12" can be just as loud as a 15" //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

thats the displacement for the 15? thanks in advance.

 

[cha0 10+ year member]

Typically speaking firing the sub up is not a good idea in a trunk car. That's the point DJ was trying to get across. In general, because you are using a trunk car, you would be better off with a smaller sub firing to the front or rear of the car than you would with the larger sub firing up.
I've done quite a bit of testing with the HD3 12 -vs- the HD3 15, and with a properly designed box there is very little difference in SPL. Firing the sub in the wrong direction will yeild a much larger loss in SPL than going from a 15 down to a 12. On the other hand from what you have said so far, it sounds to me like you have room to fire the 15 to the front or rear.

thank you, that was very informative. i never knew there was a difference in which way you fired the driver.

 

[nVRuckus 5,000+ posts]

DJ is going back and forth asking questions and such. he is really pushing a 12 in height wise but im want a 15 on tip firing up since i have such a wide and deep trunk. i dont want to settle for a smaller driver just because of the height when i have plenty of depth and width. since i have almost 8 cubes why not go 15...

I have an 18" firing up and am switching to 12s firing forward. in a trunk you can actually get louder with a 12 firing forward than a 15 firing up, it doesnt work like a hatch or suv in a trunk.