suggestions, 12 subs less than 1ft^3

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=120222
Printed Date: May 18, 2024 at 4:57 AM

Topic: suggestions, 12 subs less than 1ft^3

Posted By: 02_grandam
Subject: suggestions, 12 subs less than 1ft^3
Date Posted: February 18, 2010 at 8:08 PM

Well, I came across these today from an old friend:

[img]https://img534.imageshack.us/img534/1818/sspx0164.jpg[/img]
[img]https://img442.imageshack.us/img442/6412/sspx0163.jpg[/img]

I've had ideas for a system shake up for awhile now, going for a cleaner look rather than a huge box that now fills the trunk (Even though it produces oh so good SPL :( ) and something a little more practical for a DD. Anyways, after filling each box with water, I found one to be ~1ft^3, and the other to be ~.85ft^3.

The question is, what subs can I find that sound good in such a small sealed enclosure? I still want some nice thump, basically a decent SQ/SPL mix, leaning towards SPL more than SQ. Is there anything out there that will preform that well in that small of a sealed enclosure? Or will I have to make the boxes a bit bigger? I could probably chop the top off each one and go up, maybe make each one 1.5 cubes. I'll need to keep the power to each sub to around 400W RMS, my amp does 500W @4ohm, 900 @ 1 or 2 ohm.

So, should I build out to 1.5, or is there anything in that power range that can perform in what I've got? Also, how can I port these suckers? Can i use the round port calculator on here, and just install a round port? Thanks

Replies:

Posted By: 02_grandam
Date Posted: February 18, 2010 at 8:10 PM

posted_image

Pictures that didn't load in the first post.

Posted By: z03mz03m
Date Posted: February 18, 2010 at 9:49 PM

Maybe these:

Boston G3 Recommended 1ft3 sealed 375w RMS
Pioneer Premier TS-W1207D2 0.85 ~ 1.75 Cubic Feet 400w RMS

also the new-ish kicker 09S12C2 SOLO CLASSIC is made specifically for a sealed .88 Ft3 box but its RMS is 600W

there are a lot of subs made for small enclosures because that's the "thing" that people want now.

good luck

Posted By: 02_grandam
Date Posted: February 18, 2010 at 9:52 PM

Thanks for the suggestions.

I've decided I will be chopping them and going bigger, try to get them to 1.5-2 cubes each, since 1 cube just seems wayy too small for me. I'm figuring a wrap-around type of setup. Maybe hard to think of, but extend the back of each box out until I reach the backseat. Then, make up a fiberglass amp-rack that sits between the two.

Any ideas on the porting Q?

Posted By: z03mz03m
Date Posted: February 18, 2010 at 11:07 PM

Sounds like a good project especially since that's what I plan on doing in my protege but just on one side with the sub box/amp rack in one. Post pix on your progress if you do it in the fibreglass/fabrication forum on here.

I've been researching the "porting a fibreglass box" lately and it seems the best way to do a port would be using pvc pipe for the port and using small packing peanuts to measure the internal volume. Then use WinISD Pro to calculate the best port length/diameter. I'm new to the WinISD and there is a post on here for help using it

https://www.the12volt.com/installbay/forum_posts.asp~TID~74558~PN~1

I have also used ajdesigner software in the past and it is pretty easy to use but not as flexible as WinISD.

https://www.ajdesigner.com/speaker/index.php

both of those software(s) are free.

Posted By: 02_grandam
Date Posted: February 21, 2010 at 9:53 AM

I have the volume, and I will be expanding each to 1.5 cubes. Does it matter about the shape of the box, or just that you've reached the desired volume? Some areas are much "skinnier" than others, not sure if that would matter. How much port area/volume would I need to not have any port noise at 1.5 cubes?

Posted By: 02_grandam
Date Posted: February 21, 2010 at 3:09 PM

Here's the idea I came up with. Not going to have time to take the measurments until later this week, but heres the plan (The drawing is not to scale haha)

[IMG]https://img717.imageshack.us/img717/5885/10485885.jpg[/IMG]

Planning on having ~2 feet cubed before port displacement (Depending on whatever subs I end up going with), and port using 6" pipe with an elbow to accomodate the turn (I need 25" of port lenth (Says a calculator) for each sub, so without an elbow the lenth would not be possible)

Can I port the boxes this way, or will it just end up sounding like crap?

Posted By: 02_grandam
Date Posted: February 21, 2010 at 3:11 PM

posted_image

Posted By: z03mz03m
Date Posted: February 21, 2010 at 7:29 PM

What subs did you pick? I'm assuming you have some picked that you made the calculations for the enclosure size and port length.

What calculator did you use?

HHHmmmmm...

I thought you were going to just go straight back with the expansion but bigger is better if the calculator says so, and also I've read and had plenty of people tell me that the less SQUARE your speaker enclosure the better. I've seen plenty of ports that aren't straight especially slotted ports so I don't think the 90 degree elbow will affect anything but you do need to account for it in your total port length; um.. not sure how you do that... found it...here you go:

https://wiki.answers.com/Q/How_do_you_calculate_volume_of_a_pipe_elbow

S=R(theta) with R being the radius to the center of the pipe and theta, the angle of the bend (in radians). S will be the length in the same units as R.

so
posted_image

And about the port direction(s) that you sketched I really don't think it matters but I would go with the top pic (ports near center of car) because you will probably end up with a flatter surface to mount the port to in that area of the box if your fiberglassing.

Below is a good example of an elbowed port. He didn't use it because of space in his enclosure, but its a good reference and also check out the flare he made. You might want to try that but I would just stick with a router and a quarter round bit on both ends of the port.

https://www.diyaudio.com/forums/subwoofers/158243-first-subwoofer-done-over-top-pics-start-finish-56k-unfriendly.html

He also mentions in there that, according to one of Vance Dickason's books, 4" pipe is a Minimum port diameter for a 12" sub so you shouldn't have to worry about port noise with 6" pipe, also remember to keep the end of the pipe inside as far away from the nearest perpendicular surface as possible I think mine is ~3". Guess I'll be upgrading to bigger myself when I build my new box...When I get my Eclipse SW6210.

BTW: If you decide to upgrade your amp or for future reference the new Ice Power Class D amps are AMAZING!!! I just finished putting an Eclipse XA4200 in my car today using 2 ch for my front and 2 ch for my 12" infinity and it pounds harder and is SOOO TIGHT and CLEAN with this 200W RMS compared to the Legacy class a/b that gave it 300W RMS, not to mention the clarity up front.

Posted By: 02_grandam
Date Posted: February 21, 2010 at 7:52 PM

I was just going to go back to the forward end of the trunk, and place the amp rack on the floor in the middle, but I'm almost completly sure that won't give me my 2 - 2.5 cubes. I'm also toying with the idea of expanding at the rear of the trunk instead (Basically expanding across the back where there's nothing), so I can still can access from the cabin to the trunk and still place the amprack on the floor there. But only time and space restraints will tell there

Here's the calculator I used. Pop in the volume of the enclosure, frequency you want, and size of round port, and it gives you a lenth.

https://www./help/Articles.cfm?id=31

Should I be using another one, if this one isn't a widely used one, or something of that nature?

I don't have the subs picked out yet, this is purely planning stages, just so I can get my ideas straight and be off to the races when I'm able to build. Whatever I get should be at home in 2 - 2.5 cubes, ported at 35Hz, however I won't start building until i have my subs, so i can get as close to spec as possible. Only thing is, the port needed for a 2.5 cube box is 26" long, and takes up about .35 cubes of volume, bumping me down to 2.15 cubes if the initial design is 2.5 (***I Wonder does the calculator I posted above take that into account, or should I have 2.5 cubes after port displacement? Is there a calculator that does take it into account for sure?***)

Thanks for the lenth calculator on the bend, it will most definatly come in handy! Not sure what your talking about on that bit though, do you mean round off each edge of the PVC port?

Thanks for the help! Also, anyone else, please post your thoughts. I need all the opinions and help I can get :)

Posted By: paidnfull
Date Posted: February 22, 2010 at 4:56 PM

Have you already started redoing the box? The new solo classic kickers recomended above are pretty badass. They were designed to be run in extremely small enclosures.

Posted By: z03mz03m
Date Posted: February 27, 2010 at 9:54 AM

Sorry I've been busy at school catching up after a week off from snow ...you being a Canadian will probably laugh your *** of at that.

Anyway, Yes that port calculator should do just fine and I might use it myself because of how simple it is and I found a post by stevdart ***** Platinum member on here that recommended that calculator also. That calculator should work fine as long as the subs you get have recommended enclosure sizes which you seem to understand

"Whatever I get should be at home in 2 - 2.5 cubes, ported at 35Hz, however I won't start building until i have my subs, so i can get as close to spec as possible."

If I were you I would consider tuning to a lower frequency than 35 Hz but if thats were you like it then thats fine but since you said you were going for a little more SQ that would be a good idea. To go lower reasonably you might have to switch to 4" pipe. Also keep in mind that your subs will probably come with the recommended enclosure size, port diameter and length. Right now I have a 12" infinity in the manufacturers recommended box/port and it sounds "better" than my friends 2 Diamonds but obviously not as loud cause I'm running 1/3 the power but it hits hard never the less, rattling my whole car and making my rear view mirrors inside and out useless at times.

That calculator doesn't say that it takes port area into account but I would assume it does I might try and check it against WinISD later.

I think that was everything you asked there.