Yup. A "bending wave" is just the transverse component (which displaces perpendicular to the propagation axis).
L. Walsh details this in his patent (US3424873) Fig. 2 and section 4, line 42-71.
Cochleus, YES, stated Precisely. Instead of hearing a wavefront that being 'pushed towards' us, we hear that which is radiating 'sideways', so to speak...
That was very succinct, and straight from L. Walsh himself, if I may be a little loose with the legal language it's couched in. Thank you for that. It also does point out the 'common thread' between the Walsh, the Manger, and the German Physiks drivers that Mags and I were kicking about.
The Goebels...ehh, they're of the planar variety to my mind although they are generating 'bending waves'. They are a serious 'go' at making that physical format work well. So far there hasn't seem to be very many really good ones out there. Considering how many of this type of radiators are out there (cell phones, LCD tvs', laptops, tabs, etc.) one would think you could improve the breed...
...but it's hard to hear much 'state of the art' when your local Best Buy is all that's around anymore, unless you're in a major metropolis. And, even then, the 'better' stores seem to have 3~4 'house' brands that they actively promote.
Now, it's the 'Net, what you read and post about, and ultimately what you've decided on, 'pruned' by what you like to listen to and the way you prefer to hear it in the space you want it to be in.
(Well, that speaks volumes...*L*)
That was very succinct, and straight from L. Walsh himself, if I may be a little loose with the legal language it's couched in. Thank you for that. It also does point out the 'common thread' between the Walsh, the Manger, and the German Physiks drivers that Mags and I were kicking about.
The Goebels...ehh, they're of the planar variety to my mind although they are generating 'bending waves'. They are a serious 'go' at making that physical format work well. So far there hasn't seem to be very many really good ones out there. Considering how many of this type of radiators are out there (cell phones, LCD tvs', laptops, tabs, etc.) one would think you could improve the breed...
...but it's hard to hear much 'state of the art' when your local Best Buy is all that's around anymore, unless you're in a major metropolis. And, even then, the 'better' stores seem to have 3~4 'house' brands that they actively promote.
Now, it's the 'Net, what you read and post about, and ultimately what you've decided on, 'pruned' by what you like to listen to and the way you prefer to hear it in the space you want it to be in.
(Well, that speaks volumes...*L*)
Hi,Jim. *S* I've 'seen' you before, on my download file. 
But, thanks for suffering through that sound quality, I was almost too embarrassed to put that out and subject 'audio people' to that! IRL, they sound So Much Better. The mic in that camera will not be used again, I promise.
Part of the attraction of 'rolling (literally) your own' of these is that you get to 'play with it'. Since I shot that vid, I've swapped out the tweeters on top to a different pair. Replaced because they had an annoying *screech* at this one narrow frequency that popped up Occasionally...
Banished.
'New' one's...Much Better. Better match.
The units Finally got off the car stereo/small sub in the center, my 'test' rig.
The units you listened to are driven @ 100 a side. The Polk sub behind the
'test' set is the bass that you can't hear....at all.
It's so much better that...REALLY. I can play them quite loud for a 3" cone on a 1" voice coil of a previous 4" 3way. I resist turning them higher by remembering "...it's only a 1" vc..."... And I rather not blow them up.
....and it does So Well with that piano...
And I've not tried any serious eq....yet...*G*
Jim, look over the manual I posted. If you're comfortable with working with small tools, it's not that difficult. No heavy lifting, either..
If you have any questions, I'm not in hiding.
Think of it as getting something like a 'dirt cheap' German Physiks pair.
(Hell, I feel like a salesperson...)
Just ignore everything I've said in this post.
(...oh, and the easy way to cut aluminum tubing is with a small pipe cutter in the plumbing section...or at least, a new blade for one...)
But, thanks for suffering through that sound quality, I was almost too embarrassed to put that out and subject 'audio people' to that! IRL, they sound So Much Better. The mic in that camera will not be used again, I promise.Part of the attraction of 'rolling (literally) your own' of these is that you get to 'play with it'. Since I shot that vid, I've swapped out the tweeters on top to a different pair. Replaced because they had an annoying *screech* at this one narrow frequency that popped up Occasionally...
Banished.
'New' one's...Much Better. Better match.
The units Finally got off the car stereo/small sub in the center, my 'test' rig.
The units you listened to are driven @ 100 a side. The Polk sub behind the
'test' set is the bass that you can't hear....at all.
It's so much better that...REALLY. I can play them quite loud for a 3" cone on a 1" voice coil of a previous 4" 3way. I resist turning them higher by remembering "...it's only a 1" vc..."... And I rather not blow them up.
....and it does So Well with that piano...
And I've not tried any serious eq....yet...*G*
Jim, look over the manual I posted. If you're comfortable with working with small tools, it's not that difficult. No heavy lifting, either..
If you have any questions, I'm not in hiding.
Think of it as getting something like a 'dirt cheap' German Physiks pair.
(Hell, I feel like a salesperson...)
Just ignore everything I've said in this post.
(...oh, and the easy way to cut aluminum tubing is with a small pipe cutter in the plumbing section...or at least, a new blade for one...)
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Well I believe the principal behind all bending waves is that the voice coil simply induces waves on the diaphragm and does not actually moves the diaphragm such as in pistonic motion. Mbl loudspeakers resemble this very well and actually have some of the same principles to a degree but they are not bending wave nor where they designed to be that way but there seems to be one design which keeps it from being so. I am sure most of you guys know what it is. It seems to be pretty obvious. Where is the video attached? Is in the file? Is it possible to upload it to youtube?
Precisely, Mags. When I look at my units, I know that per the patent, I'm observing that flexion of the cones' surface. I've damped the pistonic on it relatively stiff; until I get an eq on it and quantify something half serious about it.....
The MBLs' are Obsessive. But I look at them as a serious pass @ the pulsating sphere, and they're apparently good at it. And a different animal it is; half bending wave, half pistonic but in a very different fashion than anything with a cone.
Less a flashlight, more of a vibrating bladder *L* I know...goofy analogy, but consider the source *L*.
Moi'? Obsessive? Not yet, just enjoying the investigation and the 'doing of it". And playing with not only making something that can not only sound good but (intriguing for me) is to play with what a pair or equal numbers could look like doing it. I really enjoyed a friend calling them 'sonic steampunk'. Like the MBLs', make them look like alien technology. Limited Edition Sonicpunk.
SAF? For one to consider that sort of thing, your CEO would already be down with it.
I hear I'm supposed to retire one of these days. An option to keep my hands occupied and the head moving around.....
Amazon or EBay? *LOL*
"The Vid from Audiophile HELL....coming to yourTube......*MUHhhhhaaaaaaa!*"
It's in GoogleLand. If it downloads, it can go anywhere. I've not posted to yT at all, just the occasional entertainment forays. But I'd like to redo it with any conceivably better mic, better two. At this point, all I've got to wave at it is a calibration mic, which I need to make or get a jumper for it. It's just another 'getting to it' whose numbers seen legion.
...but I doubt if I'm the only one whose "H.DO List" ends in orbit behind the space station....*shrug*
The MBLs' are Obsessive. But I look at them as a serious pass @ the pulsating sphere, and they're apparently good at it. And a different animal it is; half bending wave, half pistonic but in a very different fashion than anything with a cone.
Less a flashlight, more of a vibrating bladder *L* I know...goofy analogy, but consider the source *L*.
Moi'? Obsessive? Not yet, just enjoying the investigation and the 'doing of it". And playing with not only making something that can not only sound good but (intriguing for me) is to play with what a pair or equal numbers could look like doing it. I really enjoyed a friend calling them 'sonic steampunk'. Like the MBLs', make them look like alien technology. Limited Edition Sonicpunk.
SAF? For one to consider that sort of thing, your CEO would already be down with it.
I hear I'm supposed to retire one of these days. An option to keep my hands occupied and the head moving around.....
Amazon or EBay? *LOL*
"The Vid from Audiophile HELL....coming to yourTube......*MUHhhhhaaaaaaa!*"
It's in GoogleLand. If it downloads, it can go anywhere. I've not posted to yT at all, just the occasional entertainment forays. But I'd like to redo it with any conceivably better mic, better two. At this point, all I've got to wave at it is a calibration mic, which I need to make or get a jumper for it. It's just another 'getting to it' whose numbers seen legion.
...but I doubt if I'm the only one whose "H.DO List" ends in orbit behind the space station....*shrug*
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Bum'mer...my calibration mic is of the powered variety, so no go to record direct to the pc. Then again, it may not be the best or proper choice of type for it, given the known and noted difficulty of testing omnis' with test mics...
I wonder what type would be best suited for it...cardioid,likely. Wonder if a PZM setup would do? Hmmm..
And whats' cheap enough to consider useful enough to keep around? Food for thought.
I wonder what type would be best suited for it...cardioid,likely. Wonder if a PZM setup would do? Hmmm..
And whats' cheap enough to consider useful enough to keep around? Food for thought.
I wonder if there's a way of determining which voice coil/spider/magnet combination would work best with the needs and limitations that seem to be inherent in the design of a Walsh.
Instead of a 'motor' that can move volumes of air by pushing a larger relatively compliant cone, here we have a restrained cone (since the bottom edge needs damping) that has to be strong enough to generate the waveforms in the cone.
This restraint and resistance limits the movement of the voice coil, which seems to me to be a great way of inducing 'voice coil heat death'.
Which has just occurred for me, but it was expected. But it does indicate something to me, which is that a Walsh requires a voice coil that can create a lot of energy within a very limited range of movement.
Or, go with the 'standard model' of voice coil and deal with the surround/damping of the cone bottom edge, absorbing movement while absorbing waveforms....
An interesting conundrum. Since I don't see buying anything at this time to test this theory, I'll go with the 'standard model' and allow move movement with a different form of damping. And save the alternative for future consideration...
Any thoughts on this?
Instead of a 'motor' that can move volumes of air by pushing a larger relatively compliant cone, here we have a restrained cone (since the bottom edge needs damping) that has to be strong enough to generate the waveforms in the cone.
This restraint and resistance limits the movement of the voice coil, which seems to me to be a great way of inducing 'voice coil heat death'.
Which has just occurred for me, but it was expected. But it does indicate something to me, which is that a Walsh requires a voice coil that can create a lot of energy within a very limited range of movement.
Or, go with the 'standard model' of voice coil and deal with the surround/damping of the cone bottom edge, absorbing movement while absorbing waveforms....
An interesting conundrum. Since I don't see buying anything at this time to test this theory, I'll go with the 'standard model' and allow move movement with a different form of damping. And save the alternative for future consideration...
Any thoughts on this?
There are certain voice coils and spider/magnet combinations that will suit the walsh driver. There are no limitations but actually what makes the driver special. Though it does have limitations outside of these parameters. A voice coil that creates alot of energy in a short range is miss worded I believe. I believe you are looking for high bl factor. which is necessary in a walsh type driver for other reasons. I allowing move movement directly contradicts walsh type behavior you will end up with a weird piston driver. You do not absorb wave forms but the time till dead will shorten with any given material. Look up how to do this. There are several materials on this and I have a little library of this information. If anything I way is wrong or miss worded please correct I know I am just an amateur like the rest of some of us.
*L* Well, in this situation you're Definitely more knowledgeable about the subject than I am, believe me. And I likely have misstated exactly what I was attempting to describe. In fact, I don't have a great grasp of the parameters of speakers; a 'high bl factor' at least gives me a big hint as to what I should be looking for in the future when I make the 'great leap forward' and actually buy something specific to modify. At this point, I'm still in the learning curve of how to make these in a relatively repeatable fashion that yields at least a pair of drivers that sound reasonably the same.
Blowing up some cheap drivers' voice coils was more or less expected. I was pleased that they did what they did for as long as they did being slightly abused in the process.
I really do appreciate your thoughts and observations, Mags. There are gaps in my knowledge of what I'm doing that would likely astound you, and I think I'm standing on the edge of one of those chasms.
...and I will go educate self on 'high bl factor' so I can begin a more intelligent approach on this little adventure. What will become of it? I've got no expectations other than documenting what I'm doing, what I'm learning, and the 'whys' involved so perhaps that anyone who'd care to try this would have a guide to go by. If anything else occurs, I'll give it some consideration.
But I hope this continues to spark some interest for you. I appreciate your 'company'...
Blowing up some cheap drivers' voice coils was more or less expected. I was pleased that they did what they did for as long as they did being slightly abused in the process.
I really do appreciate your thoughts and observations, Mags. There are gaps in my knowledge of what I'm doing that would likely astound you, and I think I'm standing on the edge of one of those chasms.
...and I will go educate self on 'high bl factor' so I can begin a more intelligent approach on this little adventure. What will become of it? I've got no expectations other than documenting what I'm doing, what I'm learning, and the 'whys' involved so perhaps that anyone who'd care to try this would have a guide to go by. If anything else occurs, I'll give it some consideration.
But I hope this continues to spark some interest for you. I appreciate your 'company'...
