Yes, Paul, I mean a flat cake. Not sure whether to connect the segments with textile stripes or not.
Here is an NXT speaker that works with wooden panels (at least partly, a report in Image Hifi said it is in compound with fiber glass. The speaker was said to be really good, not mid-fi like other NXT speakers.
http://www.goebel-audio.de/
Here is an NXT speaker that works with wooden panels (at least partly, a report in Image Hifi said it is in compound with fiber glass. The speaker was said to be really good, not mid-fi like other NXT speakers.
http://www.goebel-audio.de/
el`Ol,
If you don't fill the gaps between your segments, you will have a dipole radiator that is full of holes. This will reduce low frequency output due to leakage of the out-of-phase backwave to the front. So I should definitely fill them.
The Goebel-Audio speaker did show up at NXT in Huntingdon. I seem to remember that it sounded quite good.
Paul.
If you don't fill the gaps between your segments, you will have a dipole radiator that is full of holes. This will reduce low frequency output due to leakage of the out-of-phase backwave to the front. So I should definitely fill them.
The Goebel-Audio speaker did show up at NXT in Huntingdon. I seem to remember that it sounded quite good.
Paul.
Hello Zelter,
The Sumo Aria was about 83dB. So were the later Museatex Meliors. We pulled the usual trick of quoting a 4 ohm speaker to the standard 8 ohm watt (2.83V), putting 86dB in the specification. Naughty!
The line source was only ever a prototype. It was hopelessly inefficient: Mid 70s as I recall.
Paul
The Sumo Aria was about 83dB. So were the later Museatex Meliors. We pulled the usual trick of quoting a 4 ohm speaker to the standard 8 ohm watt (2.83V), putting 86dB in the specification. Naughty!
The line source was only ever a prototype. It was hopelessly inefficient: Mid 70s as I recall.
Paul
Here is a pic of what the exciter in the SI Soundpads looks like. I have four of these I would be willing to let go for cheap. I've had my fun with them; I'm over it.
An externally hosted image should be here but it was not working when we last tested it.
Zelter,
The Arias were pretty well optimised in terms of balancing the needs for low moving mass, low inductance, efficiency and long throw, given the magnet materials we had then.
Efficiency is defined by the moving mass, the coupled radiating area, and the motor's BL product - that's B (field strength) x L (length of wire in the gap), usually quoted in Tesla Metres (Txm).
So in theory there's four ways to increase efficiency: Reduce the mass (but we already did that), increase the coupled radiating area (not so much make the diaphragm bigger, as make it stiffer), increase the L (but it then gets heavier - or shorter) or use a more powerful magnet system (possible nowadays with neodimium, but a serious engineering job).
Maybe the thing to do is to buy the most efficient full range driver you can find and cut it up for parts to make your own exciter. But most of these sort of units have very little linear throw - they try to get as many turns as possible in the gap, so you won't get much low frequency headroom. But it might be worth a try.
Those exciters look like genration one 19mm units (a guess, comparing tag size with the coupling ring). The BL probably doesn't even make 1 Txm, so they won't be very loud. You need to be looking for a motor with at least 5 Txm.
There is a range of high powered exciters with radial magnets made by Billion Sound, and similar to the Fane units. eg:
http://www.billionsound.com/eBusiness/EN/product_detail.asp?catalogid=2&productid=315
Maybe you could ask for samples... But while you'd get lots of mid-band level, the coil is almost the same length as the gap, so they will be no good at all for bass.
Paul
The Arias were pretty well optimised in terms of balancing the needs for low moving mass, low inductance, efficiency and long throw, given the magnet materials we had then.
Efficiency is defined by the moving mass, the coupled radiating area, and the motor's BL product - that's B (field strength) x L (length of wire in the gap), usually quoted in Tesla Metres (Txm).
So in theory there's four ways to increase efficiency: Reduce the mass (but we already did that), increase the coupled radiating area (not so much make the diaphragm bigger, as make it stiffer), increase the L (but it then gets heavier - or shorter) or use a more powerful magnet system (possible nowadays with neodimium, but a serious engineering job).
Maybe the thing to do is to buy the most efficient full range driver you can find and cut it up for parts to make your own exciter. But most of these sort of units have very little linear throw - they try to get as many turns as possible in the gap, so you won't get much low frequency headroom. But it might be worth a try.
Those exciters look like genration one 19mm units (a guess, comparing tag size with the coupling ring). The BL probably doesn't even make 1 Txm, so they won't be very loud. You need to be looking for a motor with at least 5 Txm.
There is a range of high powered exciters with radial magnets made by Billion Sound, and similar to the Fane units. eg:
http://www.billionsound.com/eBusiness/EN/product_detail.asp?catalogid=2&productid=315
Maybe you could ask for samples... But while you'd get lots of mid-band level, the coil is almost the same length as the gap, so they will be no good at all for bass.
Paul
Paul,
thank you for your help. I intend to use the magnet of a prosound mid or midbase speaker to do some experiments. How much y-max did you use in the Sumo Aria?
In an earlier post Moray wrote you used 150 gauge Mylar HS.
Do you still know the dimensions of the membrane?
Up to now I didn't find any review in the web. Hopefully there is someone who has some additional information.
Zelter
thank you for your help. I intend to use the magnet of a prosound mid or midbase speaker to do some experiments. How much y-max did you use in the Sumo Aria?
In an earlier post Moray wrote you used 150 gauge Mylar HS.
Do you still know the dimensions of the membrane?
Up to now I didn't find any review in the web. Hopefully there is someone who has some additional information.
Zelter
Zelter,
They were 50 x 75 cm.
By Y-max, do you mean X-max? I can't remember, to be honest. But it was something around +/- 6mm linear throw.
There is very little about the Arias on the net. There was a feature article in HiFi News, a review in The Absolute Sound, and another feature in (I think) Stereo, done by Moray after I left. I suspect there may have been more reviews of the Melior derivatives, as they remained in production for some time, but I never saw any myself.
The reason I am vague about this is that, over the course of many house moves, I have lost the file in which I kept my copies. So I too would be interested if anybody has anything they could post on this forum.
Paul
They were 50 x 75 cm.
By Y-max, do you mean X-max? I can't remember, to be honest. But it was something around +/- 6mm linear throw.
There is very little about the Arias on the net. There was a feature article in HiFi News, a review in The Absolute Sound, and another feature in (I think) Stereo, done by Moray after I left. I suspect there may have been more reviews of the Melior derivatives, as they remained in production for some time, but I never saw any myself.
The reason I am vague about this is that, over the course of many house moves, I have lost the file in which I kept my copies. So I too would be interested if anybody has anything they could post on this forum.
Paul
moray james said:
"We spent just under two million dollars in the first year and a half getting ready for production of the "Aria" which was distributed by Sumo of California."
Moray, can you give a rough breakdown of how the 2 million was spent. Are you just refering to tooling up or does this include R&D etc?
It seems like a lot of money.
Thanks, SP.
"We spent just under two million dollars in the first year and a half getting ready for production of the "Aria" which was distributed by Sumo of California."
Moray, can you give a rough breakdown of how the 2 million was spent. Are you just refering to tooling up or does this include R&D etc?
It seems like a lot of money.
Thanks, SP.
I was wromg then...
I don't haver the numbers on paper so I will guess for you. Over the time of a year and a half we probably blew through a half million or the best part of it on everything from bic pens to crazy glue, R&D the lot. Over time we spent more than two million that's for sure. By the time that Museatex had done with our invertors it was a lot more than that.
I don't haver the numbers on paper so I will guess for you. Over the time of a year and a half we probably blew through a half million or the best part of it on everything from bic pens to crazy glue, R&D the lot. Over time we spent more than two million that's for sure. By the time that Museatex had done with our invertors it was a lot more than that.
There never was $2,000,000.
Highwood (developers and manufacturers of the Sumo Aria) did have venture capital funding, but it only amounted to $500,000 (CAN), taken in two tranches. I think there was a small third round, just to keep the company going, but I had resigned by then.
Any later funding will have been related to Meitner / Museatex / Meloir. This will have been mostly electronics, not the speakers by themselves.
Moray: Stop living the lie. $2,000,000?. Try to remember what actually happened. It might do you some good.
Highwood (developers and manufacturers of the Sumo Aria) did have venture capital funding, but it only amounted to $500,000 (CAN), taken in two tranches. I think there was a small third round, just to keep the company going, but I had resigned by then.
Any later funding will have been related to Meitner / Museatex / Meloir. This will have been mostly electronics, not the speakers by themselves.
Moray: Stop living the lie. $2,000,000?. Try to remember what actually happened. It might do you some good.
My post #50
I checked back through this thread and found a reference to the article I referred to in yesterday's post #50. It was in Moray's post #13. I quote:
"Audio" June 1992 the article was titled "A New Type of Speaker, A Shere of Sound". (I assume he meant "Sphere". )
Anybody got a copy?
Paul
I checked back through this thread and found a reference to the article I referred to in yesterday's post #50. It was in Moray's post #13. I quote:
"Audio" June 1992 the article was titled "A New Type of Speaker, A Shere of Sound". (I assume he meant "Sphere". )
Anybody got a copy?
Paul
I just built this magnetostatically driven speaker with balsawood diaphragm:
There is a second arch below the table that can´t be seen in the picture with a rectangular voice coil in the region where they touch eachother. The project originates in two goals that suddenly found together: Building a line-array of bending wave transducers to overcome the max-SPL and THD problems of the manger and building some speaker with wood to explore the phenomenon of "material sound". As expected there are nasty resonances. But there are other aspects that are quite unexpected:
The material has no "material sound" at all, especially no wooden one.
It is not as precisely localizable as other speakers.
Most unexpected is that the sound is almost independent of the listening position.
The level is not very dependent on the listening distance.
The CSD is quite slow even in the region above 2kHz, where it is resonance free:
Seems that I have built no bending wave transducer but a DML. What I indend to do next is experimenting with flat diaphragms made of natural materials and NXT exciters. I heard both the Göbel and the Podiumsound at the Highend this year and my first listening Impression of my elaborate tells me it should be possible to top the performances of these two.
The problem: Where getting exciters (Fane prefered) as a private person?
An externally hosted image should be here but it was not working when we last tested it.
There is a second arch below the table that can´t be seen in the picture with a rectangular voice coil in the region where they touch eachother. The project originates in two goals that suddenly found together: Building a line-array of bending wave transducers to overcome the max-SPL and THD problems of the manger and building some speaker with wood to explore the phenomenon of "material sound". As expected there are nasty resonances. But there are other aspects that are quite unexpected:
The material has no "material sound" at all, especially no wooden one.
It is not as precisely localizable as other speakers.
Most unexpected is that the sound is almost independent of the listening position.
The level is not very dependent on the listening distance.
The CSD is quite slow even in the region above 2kHz, where it is resonance free:
An externally hosted image should be here but it was not working when we last tested it.
Seems that I have built no bending wave transducer but a DML. What I indend to do next is experimenting with flat diaphragms made of natural materials and NXT exciters. I heard both the Göbel and the Podiumsound at the Highend this year and my first listening Impression of my elaborate tells me it should be possible to top the performances of these two.
The problem: Where getting exciters (Fane prefered) as a private person?
Motorizing
The EC Motors would maybe call for renewed thoughts ?
The EC motor have parallell coils in the stator. The rotor consists of permanent magnets. Electronically switched coils controls the rpm, making frequenze regulators obsolete..
What if.... Class D-Amps. switching direct in ribbon arrays...
Or EC motors controlling a real woofer ?
The EC Motors would maybe call for renewed thoughts ?
The EC motor have parallell coils in the stator. The rotor consists of permanent magnets. Electronically switched coils controls the rpm, making frequenze regulators obsolete..
What if.... Class D-Amps. switching direct in ribbon arrays...
Or EC motors controlling a real woofer ?
Something like that is one of my options for this Project:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=109872&pagenumber=3
Seems that the flatpanel project is dead. I think I have used Google extensively and I just found one company/person who could manufacture the diaphragm to my specs, so I didn´t dare to ask for the price. Not to speak that exciters are unavailable.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=109872&pagenumber=3
Seems that the flatpanel project is dead. I think I have used Google extensively and I just found one company/person who could manufacture the diaphragm to my specs, so I didn´t dare to ask for the price. Not to speak that exciters are unavailable.
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