DIY Open Baffle Info Needed


2009-02-24 7:12 pm
Pic of experimental OB set up, using 2 disubs, active system with modded ( passive output and digital input) DCX2496 and a RX-V3800 as 6 ch pre and powerunit


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In the main system I do use four 15" woofers, two per side, one after another, like emerald physics, but with bridge over, to serve as stand for midbass and up. I used to have web page describing my dipole bass, but is was on geocities and was taken down. I have ultracurve to eq flat in my listening position, so I do not have any lack of bass, since its flat all the way to 20Hz.
I do not listen very loud (75-85dB), but occasionally have friends over, and we do crank it up. Bass is always clean, precise, no matter what level.

I do have three other systems, two of which have closed box woofers, utilizing the same 15" woofer, but the quality of bass is not there. OB done well, the bass is accurate and free of any boominess (or boxiness), for lack of better word.
One more thing, steeper slope is used for active crossover for sub then for midbass and up. Since I use midbass on open baffle too, natural roll off and first order crossover is enough. However, for sub, that is not enough, I cross much steeper.

I have a 3 way system, semi Open baffe, only for the mids and high and a bass reflex for the bass (beyma 12 b100r not suitable for on).
The mids from the BC 6md38 are very good and the sound feels live to me just when I had compression drivers...

But my question is, what do you think of the width of the on considering the mids (16cms 300-3000hz) should it be not too wide ?

But I am already enjoying my 75% system !

I do digital filtering with high slopes.



Paid Member
2004-11-10 8:31 pm
When it comes to mid, baffle width depend on lowes frequency you need to cross without significant loss. 300hz is pretty high crossover, you can easily use small baffle. Not much bigger than driver itself. Read about NaoNote.
Ideally you should measure response of each driver individually.
Hello, thanks for response.

I was enjoying the sound but then reading all the different theories I became a little be nervous, maybe I was enjoying something completely wrong (even though I have audiotechnica and focal headphones for comparison), I am not yet expert at measurements, I just play 1s of pink noise, record, and analyse spectrum in cool edit.
There is no major accident in response. As my system is active I could add some gain to the highs. Beyma 12 small bass reflex produces low frequencies in the room, never tried wide open baffle for louds but don't feel the 'slow' effect...
60-65cm is no problem for me. I have to integrate tweeter better with waveguide I can measure 2 diffraction carves.
But everything sounds lovely and live from now...


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Nelson Pass

The one and only
Paid Member
2001-03-29 12:38 am
Well, to be honest, zero design. I just bought a piece of 24X48 Bambo plywood. Decided on 18X24" so I'd have some left over for the stands. Cut a hole in the middle and mounted the Tang Band drivers I removed from a previous build.......That's it! Not very scientific, but I'm listening to them as I type this and they really do sound good!
That's the ticket. I got started with roughly the same approach. 50 years later it still works.