DIY Open Baffle Info Needed

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.
Hello,

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.

Regards
 
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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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.

:snail:
 
Open baffles aren't for everyone. They can be polarizing and take awhile for one's ears to become conditioned to the new and different sound. I listen primarily to small group acoustic jazz and vocals at lower volumes and they perform brilliantly with that genre. Before I got started into DIY I owned a pair of Zu Omens. I thought they sounded great until I built these simple flat baffles with Betsy drivers over Eminence Alpha woofers. After one listen I sold the Zu's on Craig's List.

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Open baffles aren't for everyone. They can be polarizing and take awhile for one's ears to become conditioned to the new and different sound. I listen primarily to small group acoustic jazz and vocals at lower volumes and they perform brilliantly with that genre. Before I got started into DIY I owned a pair of Zu Omens. I thought they sounded great until I built these simple flat baffles with Betsy drivers over Eminence Alpha woofers. After one listen I sold the Zu's on Craig's List.

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I agree they're not for everyone. I was very pleased with 12" full range drivers in the same baffles as these for about 2 years.
They are now in a single stereo surround, also open baffles with wings.
They use some near vintage Sansui 12" woofers, after changing to much shallower wings due to the much higher qts, and Bohlender Graebener Neo 8 tweeters. I wasn't sure I was going to stay with tweeters, so I didn't scar the baffles.
Possibly the comb filtering at the 1000 hz crossover point is lessened a bit by the limited vertical dispersion of the tweeters, but a "try" placement works well enough I'm not going to change them.
Their simple OB sound is uses in a 2 channel turntable system, and switched to be main speakers in a multichannel surround system using an AVR, where bass management helps greatly with the all OB 7.1 setup.
Maybe it's just me wanting the now vintage sound I first heard LPs with, but while I like them with.box speakers and AVR help, that's not the music sound I like with records, although it's good with concert SACDs,
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Blurays, DVDs, CDs, or streaming.
 
Buy 2 Beyma 12br70 per side and Dayton Audio RST28F-4 1-1/8"
Cross at 1000hz

 
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I'm fortunate to have salvaged a pair of 12" 49CZ852 from a 1957 Zenith console some years ago. These wide band alnico's from yesteryear have become quite sought after. Their popularity with the guitar speaker crowd is probably the reason it's easier to find a single rather than a pair. They originally came with beige gaskets but I painted these black.

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I have a pair of Zenith 49CZ852 coming to me, but unfortunately, I don't own any woodworking equipment, so this project may be on a backburner. For curiosity, what does the frequency response look like if the Zenith is run without any baffle, i.e. used as low-treble to low-midrange driver?
 
I suggest listening to them mounted in a cardboard or foam baffle ( the Zeniths weigh little ) and then with no baffle. If you like the sound of a baffle go to a cabinet shop with the dimensions and have them make you baffles.

Option 2 - Home Depot or Lowes will make all the straight cuts if you buy their material. You may even find pre-cut baffles that work. All you need for the speaker cut out is a jig saw.

http://glowinthedarkaudio.com/zenith-49cz852.html
 
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I think buying a low-cost router may be my better bet. I see the 2"x4" plywood from Home Depot/Lowe's, but man, their looks aren't going to make it in the house. How are people making these plywoods look better..? Cabinet shops sounds like $$
 
If you don't mind a little exercise, open baffles can be made with a handsaw with two saw horses and a few clamps for straight cuts and a variable speed drill and jigsaw for the holes.

For looks, I like to use hardwood panels for my baffles. Sanded plywood with a hardwood veneer works pretty well too. Or use standard plywood and brush on some paint. The wall covering is a nice idea also.

You could add some style by trimming the edges with some wooden moldings and a small miter box with a back saw.

The nice thing is that you can start with a simple baffle to see if you like the sound before going through all of the trimming and finishing steps...
 
Using a heavy textured wall covering can offer a look similar to tooled leather plus it can help deaden the baffle.

I rarely use plywood as it's a lot more expensive than MDF which is a PITA to paint. I usually cover MDF with a wall covering and then paint it.

I see a lot of folks using really thick baffles that work well for high volume levels which can otherwise cause resonance.
I mostly listen to acoustic jazz at low to moderate levels which dosen't audibly excite the baffles and 3/4 MDF with some bracing if the drivers are really heavy works for me. The MDF edges I hide with molding.

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