Building my first subwoofer (1 Viewer)

[Patrick Sun]

Max, I've merged your 2 subwoofer threads into one because I don't want to see 20 threads on the same subwoofer that you'll be building. It's best for all that your sub's discussion take place in one tidy thread. Hope you'll understand. And good luck on the subwoofer construction!

 

[Mike_Ped]

Well Max, to give you an idea...

My sonosub is approx 3 and a half feet tall and 24 inches wide. It actually doesn't take up to much space, I know this for a fact because it is in my bedroom...not to much room to begin with. Overkill? You can never have enough. I have a Tempest in that puppy with 700WATTS goin through it and I LOVE IT! I shakes the walls when I pump it up. It's like having a tactile transducer without sacrificing your couch! Plus, if you're going to move into a bigger place, build something bigger now so that when you do get to that bigger place, your bass won't be to small for the new room.

Mike

 

[Max Malloy]

Damn i really want to go for the Tempest now. One question though, how tall does the tube have to be to get good results? I'm a little confused here - someone said 6 ft, yet others have 4 ft tall Tempest subs. If i can get better performance out of a 4 ft Shiva than a 4 ft Tempest, obviously i'll go with the Shiva. I'd have to say about 5 feet is as high as i'm willing to go.

 

[jeff lam]

Like we said, it depends on the diameter of the tube. A 24" diameter will be much shorter than a 18" diameter. You pretty much have to go with at least 18" though to fit a 15" driver. A 16" tube is really pushing it and it will be about 6ft tall. You have to decide what type of alignment you are shooting for and see if that works for you. The tempest EBS will need 10ft^3 and for me, that's just too big. So I decided to go with Dan's tight Q design above.

Will get me exactly what I need in a reasonable size enclosure.

 

[Max Malloy]

Alright, so if i were to make a Temptest sub using say, a 4ft tall tube, what would it's diameter have to be?

 

[Michael R Price]

Probably 18-20". That's an internal volume of 7-8 ft^3 or so with the driver and endcaps. Big enough for the 'Adire Alignment'.

Unless you have to use a really small enclosure I think you should go with the Tempest either way.

 

[Dustin B]

The formula for volume of a cylinder is:

Volume = pi x radius^2 x height

There are 61"^3 in a L. You want a volume anywhere from 160L for the little design Hank used. 220L for an Adire Alignment. 260L for an alignment similar to mine. 320-340 for an EBS alignment.

This will only give you a rough guess (as this will be an inaccurate net volume). Mainly because you will still have to account for the endcaps, displacement of the Tempest and the displacement of the port you use. But, you still have to decide on the diameter and tuning frequency you want before you can calculate a proper gross volume (mind you these change depending on volume, so it is really hard to pick a height and determine the gross volume, much easier to pick a net volume and determine the height). Then you have to add on how long you are going ot make the legs, the thickness of the endcaps and a base plate if you decide to use one before you get the total height.

 

[Patrick Sun]

Max, it's easier to think in terms of total enclosure volume required to meet your "specs" and then put the constraint of enclosure height to determine the widest sonotube you'll need.

Once you figure out how much internal volume you need for a specific driver, then you can apply you're constraints on it.

It's not just a matter of saying "I want it be no more than 4 feet tall" but that you have to select the right driver for such constrainsts if you want to wring out the most performance out of the driver.

We don't just throw out a height number just to make it fit, it's a certain height because that's the height/width that makes for the best possible enclosure size in terms of internal volume which helps the driver performs its best.

 

[Mike_Ped]

Max, download the program supplied by Adire if you are going to go with the Tempest. That way, you can use that program to determine the size according to the best results. There is also a site out there that explains how to use the program really well. I have it bookmarked at home, but I won't be able to post it till I get home tonight. Anyone else know what I am talking about? Anyone have the link?

Mike

 

[Greg P]

Max,
I highly suggest you visit www.diysubwoofers.org. You will then be able to better understand some of our suggestions. You can not randomly stuff a driver in whatever size enclosure. There are equations you have to plug in to see what your getting with various dampining(air space) You need to learn about the drivers QTC. This affects how the driver will sound. Some people suggested a .577 QTC, but others prefer a .7 QTC which requires a smaller box. Also not all drivers need the same air space to get the same QTC. My blueprint 1503 needs less than a 2 cubic fedt to get to a QTC of .64, while a tempest requires around more than double the airspace to get to a QTC of .64.

 

[Mike_Ped]

Ok Max, here's the link to that site that outlines to use of the program supplied by Adire - just in case you decide to go with an Adire driver.
http://www.quux.net/roo/diy/sonosub/
Mike

 

[Max Malloy]

Thanks for all the replies guys.

I was wondering, what are the pros and cons of sealed and ported systems? I did a bit of reading over at Diysubwoofers, and it seems that sealed systems sound better and are easier to make?

Also, is there a site out there that lists existing designs for sonotube subs that use the Tempest driver?

 

[Patrick Sun]

There's a SonoSub link at the start of the DIY area. You'll just have to plow through all the link for different Sonosub projects to find the Tempest related ones.
If you go to the Adire Audio DIY gallery, you'll find an Adire's projects page which features projects that people have done with their drivers and kits, and there's a link for just Tempest-related projects (not all are sonosubs).