That's not the worst place to start from ... but it isn't any better than what you already have with your H frame and baffle.The more I read, the more tempted I am to just take 2 thread rods, bolt them to a base and zip tie the drivers to them
And both are much better than that large wide baffle!
The wavelength we see with our eyes cover one octace - meaning the largest wavelength is twice as large as the smallest. That makes the construction of a camera or a TV screen so straightforward (just joking).
The wavelength we hear with our ears cover ten octaves - meaning the largest wavelength (of 20 Hz) is a thousand times larger than the smallest (20 kHz). With such large difference it is plainly wrong to consider one baffle (or driver) size as good for the woofer as for the tweeter.
If you keep this 1:1000 relation in mind, you have the key to understanding modern developments in dipole design.
Well, what I have running right now is just a rectangle baffle with a 10" woofer, 6.5 midwoofer and the neo3 up top. Driver spacing is pretty close. The h frame is empty, its just a heavy base that I have the baffle with the drivers attached to.
My next experiment is going to be a baffle about the same size as this one, but with both of the 10s in it, closer to one edge than the other, and I'm going to build a spine that is attached to the motor on the 10s which extends upward and mount the mid woofer to that, and just mount the neo3 with a coat hanger wire from the top of the midwoofer basket.
My next experiment is going to be a baffle about the same size as this one, but with both of the 10s in it, closer to one edge than the other, and I'm going to build a spine that is attached to the motor on the 10s which extends upward and mount the mid woofer to that, and just mount the neo3 with a coat hanger wire from the top of the midwoofer basket.
Why don't you do the obvious - what (most) everybody else with some understanding of dipoles would do with your existing material: put both 10" into the H frame, close the 10" hole in the baffle and leave the midwoofer and tweeter in their places?
Before doing that you could experiment with tapering your existing baffle, making it narrower at the top than at the bottom. Maybe you will be content with that stage and not need a spine and coat hanger
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to Rudolf's links and your plans are 
Why don't you do the obvious - what (most) everybody else with some understanding of dipoles would do with your existing material: put both 10" into the H frame, close the 10" hole in the baffle and leave the midwoofer and tweeter in their places?
Before doing that you could experiment with tapering your existing baffle, making it narrower at the top than at the bottom. Maybe you will be content with that stage and not need a spine and coat hanger
My whole reason for moving away from the H- Frame was because the whole baffle really only needs to go down to around 90 hz to meet with my subs, and your advice in post #6 "if you don't intend to use the H or U frame below 60 hz there's no advantage." so I've only really been thinking about single flat baffles.
Really, I'm just trying to come up with the best baffle I can in order to give this experiment the best chances. The only reason I considered the huge baffle (before I read your PDF) is because the two nice BB ply boards I have that will become the permanent baffle are that size.
I know that's a bad idea after reading more on the subject, I'm just trying to figure out the best possible size and shape before I attack those boards with the saw.
These are the two I'm thinking about at the moment.
Edit: Ignore the Neo3 faceplate, that's the only model I could find to import and I'm far too lazy to draw one myself
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Here is a Edge simulation of the mid driver in your suggested baffle. I used 120mm for the driver membrane, it is typical for 150mm diam drivers (4") I set baffle width to 400mm and the shoulder at 700mm, top at 1000mm and top width 100mm.
Rudolf please - comments!
Rudolf please - comments!
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My three-step proposal:
Make the square baffle and put the dipole tweeter on top of it. Take care to keep the distance between the mid and the tweeter quite small. If the midrange appears to need less baffle width, you could cut off some triangles. If you want even less baffle for the midrange, cut off the triangulated part and install your coat hanger.
Try to keep the woofers to the floor. You want to use the Allison effect.
Make the square baffle and put the dipole tweeter on top of it. Take care to keep the distance between the mid and the tweeter quite small. If the midrange appears to need less baffle width, you could cut off some triangles. If you want even less baffle for the midrange, cut off the triangulated part and install your coat hanger.
Try to keep the woofers to the floor. You want to use the Allison effect.
My three-step proposal:
View attachment 356686
Make the square baffle and put the dipole tweeter on top of it. Take care to keep the distance between the mid and the tweeter quite small. If the midrange appears to need less baffle width, you could cut off some triangles. If you want even less baffle for the midrange, cut off the triangulated part and install your coat hanger.
Try to keep the woofers to the floor. You want to use the Allison effect.
Beautiful, thanks Rudolf
Apparently, after about 15 years of service in about a dozen different speakers, one of my Eton 7-360s has developed a crack in the surround that I can not fix with rubber glue this time. I guess I'll try my HiVi m6a and see how those work.
I'm probably officially in the market for a good pair of midbass drivers. Its a shame the neo magnet scan speaks are so bloody expensive!
V 1.0 of the baffle is done. Now that I'm looking at it, the CTC on the woofer - mid seems a little long at about 20 inches...its something to investigate anyway, I doubt it'll be a problem.
I'm probably officially in the market for a good pair of midbass drivers. Its a shame the neo magnet scan speaks are so bloody expensive!
V 1.0 of the baffle is done. Now that I'm looking at it, the CTC on the woofer - mid seems a little long at about 20 inches...its something to investigate anyway, I doubt it'll be a problem.
v1.0.
To Do:
1.) Figure out the best way to mount the tweeter.
2.) Add another piece to the base.
3.) Investigate the M6a (I don't have terribly high hopes, the motor is quite large.
4.) See if it's going to be worth tapering the baffle around whichever mid ends up in there.
5.) Drink large quantities of Tanqueray and ponder 1 - 4.
To Do:
1.) Figure out the best way to mount the tweeter.
2.) Add another piece to the base.
3.) Investigate the M6a (I don't have terribly high hopes, the motor is quite large.
4.) See if it's going to be worth tapering the baffle around whichever mid ends up in there.
5.) Drink large quantities of Tanqueray and ponder 1 - 4.
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Originally Posted by Rudolf
“The wavelength we see with our eyes cover one octave - meaning the largest wavelength is twice as large as the smallest.
The wavelength we hear with our ears cover 10 octaves - meaning the largest wavelength (of 20 Hz) is a thousand times larger than the smallest (20 kHz). “
What do you mean by a wavelength we see?
“The wavelength we see with our eyes cover one octave - meaning the largest wavelength is twice as large as the smallest.
The wavelength we hear with our ears cover 10 octaves - meaning the largest wavelength (of 20 Hz) is a thousand times larger than the smallest (20 kHz). “
What do you mean by a wavelength we see?
Just to clarify, while we were talking about woofer placement, the general consensus is that WMTW is a bad idea, so I struck those possibilities off the list, but is WWTM a bad idea as well?
I haven't done it yet, I just figured I'd make sure that's on the "don't do that." list before I cross it off any of the potential designs I have in my head.
Edit: I found some other threads where the only issue is tweeter vs ear height. At the height of my current baffle, it'd actually be closer to ear level than if it was up top.
Another idea to ponder.
I haven't done it yet, I just figured I'd make sure that's on the "don't do that." list before I cross it off any of the potential designs I have in my head.
Edit: I found some other threads where the only issue is tweeter vs ear height. At the height of my current baffle, it'd actually be closer to ear level than if it was up top.
Another idea to ponder.
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Well well well, I had forgotten about these. Old Sonogistix (monsoon) computer speakers had these in them. Last year they developed a buzz, so I disassembled them to find that the metallic coating had begun to peel off the magnet strips, so I cracked them open and peeled the rest off and applied a thin coat of polyurethane.
Never measured them to see if they work, but if they do...they might make a perfect little midrange!
Blah, I don't think I got the diaphragm tight enough.
Never measured them to see if they work, but if they do...they might make a perfect little midrange!
Blah, I don't think I got the diaphragm tight enough.
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If it moves the midrange driver even more away from the woofers, it is no good idea. I believe that those 20 inches already are "ambitious" enough.
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