Cardboard 10" DOS sub project

[ppataki]

Now let's see some measurements!

From 1cm at (almost) 100dB, no DSP whatsoever

Frequency response and phase:

Distortion:

Group delay:

IR and Step:

Wavelet:

Some other observations:
- zero motor noise, these SB drivers are of really high quality
- practically zero cabinet vibration due to the DOS design (as expected)
- cabinet is totally airtight

All in all I am super happy!!!

Next steps: finalize the second cabinet, test it then start the paint job (ultra matte white chalk paint)
Moving to my new house approx. end of June

 

[ppataki]

And finally, the looks

I applied 3D printed rings on the two ends to provide a kind of a futuristic look

The shock absorbers are Swissonic Riser XL (by Thomann) - I have been using them with my 15" DOS sub too, I think they have a really great price/value ratio

The feet are also 3D printed, they do not touch the ground + there is a self-adhesive, foamed EPDM sealing tape applied between the sub and the feet

I consider this project to be finished from the build perspective
Next update is when I give them a try in stereo in my current living room then comparing them in the living room of my new house

 

[kemmler3D]

Wow, nice measurements. Looks great, my only critique would be the small gaps in the rings you added on the ends, but I imagine that is correctable during the finishing process somehow. I'm a little surprised that the tube is able to handle this usage so cleanly... nice! I imagine people might want to replicate this design since it seems pretty easy compared to building a box the normal way.

 

[ppataki]

Wow, nice measurements. Looks great, my only critique would be the small gaps in the rings you added on the ends, but I imagine that is correctable during the finishing process somehow. I'm a little surprised that the tube is able to handle this usage so cleanly... nice! I imagine people might want to replicate this design since it seems pretty easy compared to building a box the normal way.

Thank you, appreciated!

Those gaps are unfortunately intentional, due to the size constraint of my 3D printer
I will be able to get rid of those once I upgrade my printer to a bigger one (planned later this year)

The tube is totally fit for this purpose, especially with the butyl treatment - what's more, one could further up the game by using CLD but because of the DOS design I did not deem that necessary
However, in the near future I am planning to upgrade my 8" woofer cylinder cabinet with that - I am wondering if there would be a measurable difference

One thing to note: instead of painting, one could use self-adhesive foil or even better: 3D print a cover fully or partly around the tube (that is also planned for later once I upgraded my 3D printer)

 

[kemmler3D]

Thank you, appreciated!

Those gaps are unfortunately intentional, due to the size constraint of my 3D printer
I will be able to get rid of those once I upgrade my printer to a bigger one (planned later this year)

The tube is totally fit for this purpose, especially with the butyl treatment - what's more, one could further up the game by using CLD but because of the DOS design I did not deem that necessary
However, in the near future I am planning to upgrade my 8" woofer cylinder cabinet with that - I am wondering if there would be a measurable difference

One thing to note: instead of painting, one could use self-adhesive foil or even better: 3D print a cover fully or partly around the tube (that is also planned for later once I upgraded my 3D printer)

Every printer eventually runs out of bed space for something you want to build... I guess the trick is to cover / fill gaps as needed.

I think printing a cover to go around the tube is an interesting idea. But at that point... I guess you don't even need the tube? Just print it and reinforce it with something?

 

[10PSPMemSticksForMiku2007]

Great project, and you made it look about as beautiful as such a design can be. I also like this format. I made a similar subwoofer once though a bigger one and it was ported, tuned to about 17hz. I used two plastic bins combined with a wooden baffle on the bottom of each and in the middle. The dual opposed system works well as long as your material is stiff enough to transfer the force between the two baffles without bending.
You can also get a significant reduction in even order distortion, as well as a little more internal volume, by inverting one of the subwoofers to a push pull configuration. (you also invert the wiring to this speaker of course). The effect is supposed to work better the closer the woofers are, but it still had a good effect with them a few feet apart. Downside is looks, although mine was already ugly, and possibly more mechanical noise. Maybe you would be interested to try it and see if there is any difference in your measurements. However the lower quality the drivers you use, the more pronounced the improvement would be.

 

[roundsound]

About 10 years ago, I made some DIY Rythmik subs out of cardboard tubes. I had the local company spin on more cardboard layers for a total thickness of 20 mm. The company also sold MDF discs of the right diameter so it was an easy project (expect for the veneering...)