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Open Baffle Epiphany!

portnoy said:
I've been thinking about trying open baffles for a while so I finally dipped my big toe in the other nite.
I really do like the way they sound. The Magnavox 15" drivers are a little light on the low end so I'm augmenting the low end with a couple of subs.
I think I do need to think of the most efficient layout of the drivers so I can make something smaller in overall dimensions.

Cheers,
Wayne
Click to expand...

Surprised no one mentioned this but I noticed most OB users prefer their woofers close to the floor.
As far as the layout how about something like these here: http://glowinthedarkaudio.com/openbaffle.html
...a combo of the first and last picture, woofer near the floor, tweeter(s?) at ear level and the mid right below.:scratch2:
 
In this 3 way tri-amped OB a tweeter was used as the Eminence Beta 12LTA wide bander needed a little help on the top end. Whereas the Lowther DX3 in my signature extends high enough to go it alone.



picture.php
 
My open baffles completed

These sound amazing,should have done it years ago.
 

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Drivers are Dayton 10" #DC250-8 25hz to 2500hz
Tweeters,Dayton silk dome # DC28F-8
Crossover,Dayton #260-142 1300hz to 20k
They are wired for 4 ohm
It's surprising how good the midrange is on these. I am truly amazed how good they sound.Theae probably won't see the living room set up and remain in the shop or studio but I think I may have another another go at it with different drivers although I'm quite happy with these. Did I say that?
MDF for the stands.Doubled up on the bottom piece for weight.Three feet on the bottom.I sealed the ends of the MDF with hide glue,then primed and painted.
 
I have had my open baffles since December of last year, and have finally found a combination of electronics that work well with it. These speakers are pretty efficient, but didn't like my Electra Print 300B SET amp. So after a few false starts, I have found a First Watt Mini J clone and a DIY B1 pre-amp that works wonderfully with these speakers. There is a wonderful tonal balance, remarkable low level resolution, nice imaging, and darn good dynamic expression. I still need a sub to fill in from 50 hertz and below, but that is to be expected. The system is good enough to show all the limitations in a multi track commercial recording, but it still sounds good even though its obviously flawed. Now a good recording sounds sublime, with detail and nuance that is on par with many a good quality SET and horn set up I have heard. Now the system doesn't quite have that tube warmth and texture, but I find that too much of that really kills the music for me.

But with that being said, I am having an F6 built, which might have a bit more body than the Mini J does. As good as the system sounds now though, I am not sure I really should have ordered the F6. But I am sure I can move either amp once I make a choice, although I suppose I could see a scenerio where I keep both.

But this combination of higher efficiency speakers and the First Watt amps is really nice, and I am glad I took a chance and experimented. It was money well spent.

Regards
Mister Pig
 
I'm going to try these with my Decware set amp and see how they perform.
Been running them with a 2285B and a Sansui 9090db.certainly no lack of bass like some people have experienced.I started with one woofer when they were in the experimental stage then added a second and the bottom really came alive.Pushing more air I guess.My first speaker build and I got lucky.
 
Thread bump!

40+ pages back!
Here is some info + pics on my latest project - pales compared to others posted here but I like them.
Started with modded Altec 619 ceiling speakers. 15" duplex. I didn't like the tweeters & when I had one apart to replace a voice coil I noticed a bolt on horn adapter fit. So some cheap Pyle compression drivers were swapped on.Added a modded horn also.
These made great bass in a cabinet but nothing on open baffle so I added GRS 15PF woofers.(cheapskate here).Not bad but not quite enough so added 2 more. Highly recommend these woofers at $30 each at PE.
Havent been out to the cave today to get pics of progress made last night & headed out to family diner now.
Will post more info & pics. later.
Happy T-day!
 

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Progress

Sounding pretty good! More tweeking to do but so far so good.

Preamp - Maratz 7( lol) from Hong Kong with vintage Motorola AX7 tubes.
Parametric Eq - SAE 180
Amp powering Altecs - Magnavox console pull 990?
Amp powering woofers - JBL 6230
X over for woofers - Behringer CX 3400

Been trying different xover points for the woofers & tried both stereo & low summed.
Sounds best to me low summed 80-100hz. range.
Have some 200uf motor run caps on order to block some of the bass too the Altecs.
Using about 8 uf total on horns.
Thanks pioneerguy & thanks to everyones input on this thread.
I have followed it from the beginning so I hope I have learned a little......
 

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I've been an OB convert for years now, but the most difficult part of the experience has been making OB bass work properly. I absolutely love the quality of OB bass but getting the quantity and reach has always been the tricky bit. I personally don't care for the high Qts route as I feel it affects the SQ. Comparing Qts of 1.2 and 0.3 drivers it became apparent to my ears that the SQ of the lower Qts drivers was preferable.

Please check out the following links. Graham Maynard proposes a solution to optimize lower Qts drivers for use in OB, even with narrow baffles. Everyone who has actually implemented his solution seems to agree that the effect is not subtle and is beneficial.

I've ordered the requisite trafos and will be working towards a working prototype ASAP.

Here's the links:

http://bovan.net/gmweb2/new_page_1.htm

http://www.diyaudio.com/forums/full-range/130679-t-bass-drive-ob-lf-drivers.html

Oh, and why not add Nelson Pass' contribution: Slot Loaded OB bass:
http://www.firstwatt.com/pdf/art_slob.pdf

I hope some of that is of interest and contributes to the discussion.
 
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