Using Sonotube for Sub Building

[mrogowski 5,000+ posts]

A ca.com member requested I do a short write-up about Sonotube use in subwoofer builds. Firstly, I do not claim to be the end all, know all of Sonosubs so if there is something I missed, please feel free to add it to this thread.

A very brief history on Sonotube usage:

Sonotube builds really began to blossom when Dr. Hsu made a splash with his commercial Sonotube-based subs for home audio back in the late 80's. He took an otherwise simple design/build method and literally made a ton of money off it. The tubes were cheap, the assembly was fast and the result was a low-cost, extremely good sounding product that was aesthetically pleasing.

Fast forward to now and you will find many DIYers using Sonotubes in the construction of home theater subs. The advantages that Sonotubes have over the square box counterparts are:

- They are light weight

- They simplify a "box" design and build; Sonosub projects can be banged off in an afternoon

- Sonotube is widely available and comes in sizes 6 - 24" (may even be larger sizes but the biggest I've had is 24")

- Vibrations are dispersed evenly around the tube so internal bracing is not needed

- Finishing the tube is simple using coloured fabric or carpet of choice

Of course, there are downsides to using Sonotubes in sub building as well:

- You are limited to where you can place your driver

- Mounting of a port becomes problematic if you are not placing it at the end (but not impossible)

- Depending on the size/length, they can be quite clunky

- Length of port may be restricted because of overall tube length

- Placement in a vehicle can be an issue

- You may not like the looks of it

Constructing your Sonosub:

Sonotubes come in even number diameters, so if you have a 10" driver look into getting a 12" Sonotube; 12" driver, get a 14" tube, etc. Calculations for Sonotube volume are simple:

Cubic Foot Area = 3.14 x Tube Radius^2 x Tube Length in Inches / 1728

You can apply the same calculations if you intend on using a round port as well.

End Caps:

Many folks like to use two 3/4" (glued) layers of MDF for their end caps. They cut the first layer to fit inside the tube, and the second layer to cover the outside "lip" of the tube. The result is an end cap that provides sufficient baffle strength and inside area for gluing and sealing. The outside lip of the MDF can then be routed to provide a nice rounded finish if desired.

Remove the Wax Coating!

The inside of the Sonotube is covered with a thin plastic waxy film. Make sure to peal this film off prior to gluing your end caps. Don't make the mistake I did - the end cap popped off my first build because the glue couldn't adhere to the coating.

Ports:

Depending on your design requirements, you can make use of the smaller Sonotubes for ports. This too is a good cheap alternative to ABS or PVC piping. As mentioned there are various sizes available - the smaller ones usually come in a "6+" and "6 -" diameter; 6+ is usually about 6 1/4" while 6- is about 5 7/8". Make sure you verify these diameters when designing your ported Sonosub.

Further Reading and Sonosub Program:

Collo has an excellent website dedicated to all sorts of geeky stuff including Sonosubs. I recommend you check it out:

http://www.subwoofer-builder.com/index.htm

He has also created a program that will calculate everything for you. It is simple to understand and worth the download. You can pull it off his site or click the link below:

http://www.mach5audio.com/download/sonosub.exe

Hope this sheds some light on the subject.

Mark

Click to read more...

 

[gymfreak101 10+ year member]

very good write up, I actually bought some of the tubes this weekend from Lowes, and thanks for mentioning the wax coating I would have left it in. I doing this project with a DLS Nobelium 12 I have laying around.

 

[mrogowski 5,000+ posts]

very good write up, I actually bought some of the tubes this weekend from Lowes, and thanks for mentioning the wax coating I would have left it in. I doing this project with a DLS Nobelium 12 I have laying around.

Great, let us know how it turns out.

 

[Xprime4 10+ year member]

yeah good read. I bought some sonotube from home depot at a whooping 10$ for 10feet of 8inch. I wouldn't have use pvc in my life know those easy to work on tubes.

 

[tez4life Premium Member]

Great write up Mark, I was in Home Depo last night looking for some stuff for the house, and saw some Sona tubes and started to get some ideas. Thanks.

 

[mlstrass 5,000+ posts]

Thread saver pic //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[mrogowski 5,000+ posts]

Prime example there folks //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[bamaboy 5,000+ posts]

easy to build and works great for subs

pic of mine id did for my tc2000 12

while i was building it, and its upside down fyi

dont know if you mentioned it, but try and make sure you get the 1/4" thick one

easiest place to find one for me was the PSP basscore tubes, on thriller audio for like 25$,and shipping was cheap when i bought mine

 

[Lakota 5,000+ posts]

Coolness. I've found it interesting that all the street guys in dB Drag have gone back to rectangular boxes.

 

[BigJoker 10+ year member]

Thread saver pic //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

whats that cheap crap? //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

 

[CoilBurner]

Anyone know anymore about these. I was thinkning about making one out of a 20' or similar tube for a single 18" driver if I can find one locally

I dont get how you might place the port though, just simple straight out the back?

Would the box still sound good with the sub woofer pretty much just shooting right out the back of the box...??

 

[bilug 10+ year member]

My sonotube is the only one I've seen like it. A car stereo shop built it back in the late 80's.

Mine has a speaker in each end of the tube and a square port in the middle. There is no internal divider, both speakers share the tube.

Sounds killer.

 

[O.G. D-Wet 10+ year member]

My sonotube is the only one I've seen like it. A car stereo shop built it back in the late 80's.Mine has a speaker in each end of the tube and a square port in the middle. There is no internal divider, both speakers share the tube.

Sounds killer.

blah blah blah pics!

 

[CoilBurner]

Its gonne be a ***** to find a 20" sonotube, but Im gonna ****in try

 

[mlstrass 5,000+ posts]

concrete supply places will have sono up to 36", probably bigger.

Port/sub on the same end or port on end opposite of the sub...