While building my new open baffle mid/high speakers, I have been experimenting with a variety of baffle shapes. I have been using The Edge to model them, then building test baffles from a bunch of 1/4" paneling I salvaged from someone's trash. This material certainly isn't ideally stiff or strong, but it was free, I have a LOT of it to use, and it's very easy to cut up.
I have tried some unusual configurations of shapes and driver mounting, and I find that the best sounding shapes are the oddest, with lots of irregular edges. I tried tombstone shape to begin with, and they were awful. Next came some flying wing shaped things, and those were better. Now I have a monstrosity that looks like a jagged piece of alien spaceship, and damn if it doesn't sound absolutely marvelous, with very smooth FR and lots of 3D and great imaging.
Most of the designs I've seen in commercial production or presented here for DIY have very regular shapes. It seems that most designers have not really broken away from the simple enclosure-type shape that usually needs to be coupled to the back of a baffle. Have any of you experimented with really bizarre shapes, or are you aware of any commercial designs that feature something more unusual than the rectangle or triangle with rounded corners?
Once I fine tune this thing, I will gladly share pictures and my design philosophy.
Peace,
Tom E
I have tried some unusual configurations of shapes and driver mounting, and I find that the best sounding shapes are the oddest, with lots of irregular edges. I tried tombstone shape to begin with, and they were awful. Next came some flying wing shaped things, and those were better. Now I have a monstrosity that looks like a jagged piece of alien spaceship, and damn if it doesn't sound absolutely marvelous, with very smooth FR and lots of 3D and great imaging.
Most of the designs I've seen in commercial production or presented here for DIY have very regular shapes. It seems that most designers have not really broken away from the simple enclosure-type shape that usually needs to be coupled to the back of a baffle. Have any of you experimented with really bizarre shapes, or are you aware of any commercial designs that feature something more unusual than the rectangle or triangle with rounded corners?
Once I fine tune this thing, I will gladly share pictures and my design philosophy.
Peace,
Tom E
I'll not embarrass myself by posting pictures of these monstrosities. These things turned into a total bust when I connected a xover and tweeter.
Thanks for the tip on the lopsided pentagon. I tried that next, and it's still not working. Frustration level is getting very high now.
After numerous experiments and lots of sawdust and swearing, lots of modeling baffles and mounting drivers and tweaking crossovers and listening, I'm ready to throw in the towel on this OB thing. There are simply too many contradictions involved, and I can't master the subtleties of design required. I also can't accept the use of massive amounts of EQ to get decent FR. Seems that any baffle large enough to produce anything close to decent low or even midrange FR is so large that it completely messes up HF.
What a can of worms! I guess there are many good reasons why most speakers are put into enclosures, Linkwitz notwithstanding. I've heard lots of nice music during my OB experiments, but never anything totally satisfactory. I have also heard (and made) lots of nice box designs that produce great imaging and spatiality along with a smooth FR. Making good boxes has got to be easier and more rewarding than this stubborn OB thing.
Good luck to you guys who are addicted to OB sound. I quit.
Peace,
Tom E
Thanks for the tip on the lopsided pentagon. I tried that next, and it's still not working. Frustration level is getting very high now.
After numerous experiments and lots of sawdust and swearing, lots of modeling baffles and mounting drivers and tweaking crossovers and listening, I'm ready to throw in the towel on this OB thing. There are simply too many contradictions involved, and I can't master the subtleties of design required. I also can't accept the use of massive amounts of EQ to get decent FR. Seems that any baffle large enough to produce anything close to decent low or even midrange FR is so large that it completely messes up HF.
What a can of worms! I guess there are many good reasons why most speakers are put into enclosures, Linkwitz notwithstanding. I've heard lots of nice music during my OB experiments, but never anything totally satisfactory. I have also heard (and made) lots of nice box designs that produce great imaging and spatiality along with a smooth FR. Making good boxes has got to be easier and more rewarding than this stubborn OB thing.
Good luck to you guys who are addicted to OB sound. I quit.
Peace,
Tom E
Tom, sorry to hear of the frustration but remember, the failures make you stronger, or something like that 
I must say though that the thought of OB bass has always confused me and I share your concerns. OB to me has been an eye opener when it comes to midrange though. The open airiness of it is something I will try to incorporate in as many speakers as I can in the future, but again, the bass thing I just don't get. The baffles have to be too big and the driver motors too small. Non comprende.
I must say though that the thought of OB bass has always confused me and I share your concerns. OB to me has been an eye opener when it comes to midrange though. The open airiness of it is something I will try to incorporate in as many speakers as I can in the future, but again, the bass thing I just don't get. The baffles have to be too big and the driver motors too small. Non comprende.
I've never gotten the feeling that baffle shape was a silver bullet. You can make a bad baffle but you can't make one that cures cancer.
Assuming a box/baffle of nominal proportions and thoughtful driver choice, the real work is in the crossover regardless of the alignment.
I've gotten past the feeling that EQ=evil. It seems to me that any full-range loudspeaker has quite a bit of filtering.
As for bass, my Lambda Dipole12 drivers have pretty big magnets. I think folks are exploiting the OB friendliness of less endowed woofers more than a small magnet being a requirement.
Assuming a box/baffle of nominal proportions and thoughtful driver choice, the real work is in the crossover regardless of the alignment.
I've gotten past the feeling that EQ=evil. It seems to me that any full-range loudspeaker has quite a bit of filtering.
As for bass, my Lambda Dipole12 drivers have pretty big magnets. I think folks are exploiting the OB friendliness of less endowed woofers more than a small magnet being a requirement.
I am a huge proponent of EQ... it's not the EQ that is evil but the people who don't know how to use the EQ that is evil.. though it's always best practice to build properly first and then fix minor issues with EQ... IMO this is the next true evolution in home audio.
Now back on topic... I love creating pieces that put a smile on your face or something you can't stop staring at while passing by..
my pieces
Now back on topic... I love creating pieces that put a smile on your face or something you can't stop staring at while passing by..
my pieces
ultrachrome said:
re:''I'll not embarrass myself by posting pictures of these monstrosities'' - aww, go on
Just as a matter of interest, which drivers are you using?
as for bass, I'm with Cal, I prefer the solidity of a well tuned BR.
OB is nice in theory, but to my mind the room becomes the box, the problems just shift outwards...
That said, I'm going to revisit my OB speakers sometime this year (they take up too much space to ignore ), these sounded OK to me when I did them, a bunch of old High-Q drivers (1x12'', 1x10'', 2x8'' & HF horn) on a 'no-box' style baffle ~46Cm wide, with a simple 1st order series xover, and a smidge of bass boost on the tone controls...
(although I'd rather have something as beautiful as Trusound has produced)
Just as a matter of interest, which drivers are you using?
as for bass, I'm with Cal, I prefer the solidity of a well tuned BR.
OB is nice in theory, but to my mind the room becomes the box, the problems just shift outwards...
That said, I'm going to revisit my OB speakers sometime this year (they take up too much space to ignore
), these sounded OK to me when I did them, a bunch of old High-Q drivers (1x12'', 1x10'', 2x8'' & HF horn) on a 'no-box' style baffle ~46Cm wide, with a simple 1st order series xover, and a smidge of bass boost on the tone controls...(although I'd rather have something as beautiful as Trusound has produced)
I just spent some time going through this thread on MJKs Goldwood H-frames.
I knew the design was passive but I was not aware he was using no shelving on the woofer. Very impressive.
OB makes bass quite well assuming you've picked your drivers, baffle design, and crossover accordingly. The same is fair to say for any alignment. But you may well need to hear it to believe it.
I knew the design was passive but I was not aware he was using no shelving on the woofer. Very impressive.
OB makes bass quite well assuming you've picked your drivers, baffle design, and crossover accordingly. The same is fair to say for any alignment. But you may well need to hear it to believe it.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.