Chaps,

Still a work in progress, but I thought you might be interested in my homebuilt isobaric coupled cavity subwoofer, it should be quite something when it is finished - at least it had better be given the amount of time I seem to be spending on it.

http://www.yourmissus.com/

Let me know what you think, I'm still at the woodworking phase, but the drivers arrive tomorrow!!

Cheers
-Dan

[Import racer]

Originally Posted by toastyboy

Chaps,

Still a work in progress, but I thought you might be interested in my homebuilt isobaric coupled cavity subwoofer, it should be quite something when it is finished - at least it had better be given the amount of time I seem to be spending on it.

http://www.yourmissus.com/

Let me know what you think, I'm still at the woodworking phase, but the drivers arrive tomorrow!!

Cheers
-Dan

personally think isobarics are the best subs !!

Nice to see someone having ago at building a decent sub box , with the amount of effort you have put in, it should sound great.

Nice info links

cheers
steve

[Nimby]

Congratulations on a superb, well illustrated article. A great resource!

I built a pair of passive 6th order series bandpass boxes with SEAS 10" units about 15 years ago.

20-120Hz(-3dB) with 100dB capability and max 100 watts handling to perfectly match Linn Kans or LS3/5as.

I loved them until I moved onto an SVS cylinder and now a 4 x 15 IB for film and music.

You are in for a treat if you drive yours properly.

The drivers (speakers) turned up a couple of days back, so they are in now!

www.yourmissus.com

-Dan

[Nimby]

How does it sound?

[Russell.Williams]

Eminence market the Beta 10 as optimzed for mid range use - 400-4000Hz I think they quote, although they do mention it's suitability for bass guitar. I'm genuinely interested to know how it suits this sub bass application.

Casting my (extremely) amature eye over it, it seems to lack travel, have a noisy corrugated surround and T&S parametres that would seem to rule it out.

I really am genuinely interested to know as I have been feeling the urge to start dabbling in DIY subs for a while and as it currently stands, anything is a possibility.

Russell

PS. great job on documenting the build.

[Nimby]

My 10" SEAS units had roll surrounds and nice low Fs.
But they was taken off the market soon after I built mine.
I ought to try them with REW but they weigh a ton and getting one upstairs could be a problem.

Keep us informed, Dan. Love the website.

Cheers everyone.

Russ, to be honest, my design is loosely based around an article in Electronics the Maplin Magazine from 1995, written by David Purton, in the 3 part article he explains how coupled cavity sub woofers don't tend to rely on the quality of the woofer itself - which is a massive bonus if true, and to be honest did seem to be the case when I built the last pair.

regarding how it sounds, I've still lots to do regarding lining the box, wadding, etc.. but I'm running the cones in as we speak, after 100 hours or so I may start some testing.

Thanks for your interest.
_Dan

[Russell.Williams]

Thanks for that.

I can sort of envision what you're saying as the drivers have to exite the air in the ports to provide output as opposed to directly radiating themselves, plus theoretically the opposed drivers should cancel their own non linearities

I'll certainly be very interested to see the measured results. The band bass designs I've seen measured (and it's not many) seem to either have a 'twin peaks' response curve or don't go very deep, whilst port noise can lead to serious distortion near fb. They all seem to ge very loud though.

Russell

[AngelEyes]

Great documentation on your project there, can't wait to hear how it performs

Adam

[Nimby]

It was David Purton's "The Coupled Cavity Handbook" which got me started on bandpass subs. I have the first edition I think.

A later edition is supposed to have far more examples using different drivers. I heard there was a notch filter included to take out the likely peaks in the response. Probably the major port/pipe fundamentals.

Here's Purton's computer prediction for the design I used.

Nimby, I'm expecting a copy of the coupled cavity handbook to arrive on my mat soon.

I've made a bit of progress since posting last:

www.yourmissus.com

Cheers
-Dan

[Nimby]

Originally Posted by toastyboy

Nimby, I'm expecting a copy of the coupled cavity handbook to arrive on my mat soon.

I've made a bit of progress since posting last:

www.yourmissus.com

Cheers
-Dan

Really? Where did you manage to source a copy?

I have to admire the way you've presented your project.

An example to us all.