do you think

[vasyachkin]

anybody would be interested in a driver that had the following specs:

* 115 db/watt efficiency

* 150 W power handling

* 300 hz - 30 khz response

* good dispersion patter horizontally and vertically across the entire operating range

and did all that using about 20 dollars worth of raw materials ?

it would also look better than any driver you have seen

:)

all i had to do was take the best technology and make it 10 times better by putting it on its head :) can you guess what it is ?

:)

i wonder if there is any point in trying to explain how it works. bill fitzmaurice would probably understand but i don't think anybody here would be able to actually build it.

by the way this concept could be applied to anything from midrange to supertweeter.

[Max_Andrews]

make it out of antimatter and power it with energy siphoned from your all-knowing aura of gravitons?

[bobblickle]

Vas,
I've got $40. I'll take 2. You want my address? :D

[vasyachkin]

Vas,
I've got $40. I'll take 2. You want my address? :D

lol. no you have to build it. it would also be not trivial to design or fabricate. basically it would all be about the phase plug. you could make it out of any cheap plastic but the shape would be complex. it would be a little bit like building a ship inside a bottle :) only the ship would have to be computer optimized and built to exact tolerances lol !

[billfitzmaurice]

bill fitzmaurice would probably understand but i don't think anybody here would be able to actually build it.
I understand that it's impossible to achieve that performance from a moving coil driver mounted in a direct radiating enclosure. OTOH there are horn compression drivers that exceed that when properly loaded.
BTW, sensitivity is measured in dBs. Efficiency is expressed as a percentage figure.

[vasyachkin]

OTOH there are horn compression drivers that exceed that when properly loaded.

i don't think so.

you would need a 4" driver or so to hit 300 hz which unless it was made out of beryllium would have pretty c4appy response above 10 khz.

but yes of course i am talking about a compression driver. the improvement would come from doing the phase lens ( or whatever you call it ) differently. horn would have to change completely as well. there is also a second upgrade to the diaphragm itself that is optional and would increase performance even further if you need it.

basically the change to the lens and horn that i came up with would essentially remove driver size as a variable in high frequency response - you could have all the top end you want from any size driver.

the optional change to the diaphragm would merely increase power handling and off-axis response both by a factor of 2.

i really don't feel like drawing diagrams though, i could try to explain in words ?

:)

[Green Machine Mowing]

if this is sugh a darn good idea, then why havent the big guys, like JBL picked it up??

[vasyachkin]

if this is sugh a darn good idea, then why havent the big guys, like JBL picked it up??

because the traditional design is easier to make.

[billfitzmaurice]

i don't think so.

you would need a 4" driver or so to hit 300 hz which unless it was made out of beryllium would have pretty c4appy response above 10 khz.
http://bmspro.com/Specification.specification4.0.html

[mike1234]

I think Bose is looking for a new Acoustic Wave gilfridgit to sell.:D

[vasyachkin]

http://bmspro.com/Specification.specification4.0.html

coaxial - disqualified !

:)

[nick29498141]

make it out of antimatter and power it with energy siphoned from your all-knowing aura of gravitons?

Dark Matter is more "musical" IMO... :p

[nick29498141]

GOTO Unit has exceeded it, but their compression drivers cost $65,000+


NK

[vasyachkin]

GOTO Unit has exceeded it, but their compression drivers cost $65,000+

NK

you are giving me headache

your post is so wrong i don't know how to answer it

go away !

[greysplash]

Vas is the Greg House of the P.E. forums.....

[nick29498141]

you are giving me headache

your post is so wrong i don't know how to answer it

go away !

I'll stick around, and give you time to think of a proper response. :p

[toddshore]

Vas is the Greg House of the P.E. forums.....

Nah, he just complains and postulates about the patients of others. He doesn't have enough patience for patients.

[brianpowers27]

How about a large surface radiating ribbon with a horn reversed to funnel the frequencis into a forward facing horn!:cool:

[vasyachkin]

How about a large surface radiating ribbon with a horn reversed to funnel the frequencis into a forward facing horn!:cool:

ribbons are expensive. i said $20 worth of materials not $200 worth :)

basically i think that compression tweeters are on the right track. they have lightweight but large diameter voice coil. lightweight diaphragm that at the same time does a pretty good job of resisting deformation due to being shaped like a dome. they also have optimum loading.

there is a fundamental problem with domes though and its off-axis response. this is because the high-frequency energy is being generated at the very perimeter of the diaphragm.

in this respect a regular woofer is much better because it generates the HF energy closer to the center better approximating a point source where it counts ( where wavelengths are short ).

when you take a 4" compression driver and give it 1.5" horn mouth that improves the situation somewhat because 1.5" is more of a point source but still not good enough.

now how do they go from 4" driver to 1.5" horn mouth ? they use 3 or 5 or whatever slits. problem is all the HF energy still stays on the outside except now its on the outside of a 1.5" circle instead of 4" one.

what i am suggesting is to redesign the phase lens such that the slits cross over each other and the ones from the outside of the diaphragm come out in the center of the horn mouth. this will be rather complex to design as well as manufacture but can be made out of plastic so in the end shouldn't be terribly expensive.

thats not all of it though because you still need the HF energy to couple properly to the horn itself. this is easy. you simply make several concentric horns like russian dolls. inner horns don't have to be as large as outside ones as their job would be to shape only the HF response and the outer large horn would help them with midrange.

each slit ( remember you had like 3 or 5 slits ) would couple to its own horn directly.

so out of 1 diaphragm and 1 voice coil you now have 3 or 5 coaxial horns and ability to optimize dispersion across the entire operating range.

you also no longer need the diaphragm to operate like anything close to a piston. you can now replace a 4" beryllium diaphragm with cheap mylar film or whatever and still get the performance you need.

this is basically like a coaxial speaker only much better. because you don't need a crossover and you can't possibly fry the tweeter because there isn't any tweeter. the tweeter now is simply the region of the diaphragm that is in direct vicinity of the voice coil ( say within 1/4" of it ).

there is virtually no limit to performance. simply by increasing the size of diaphragm and number of slits in the phase lens you can make it go lower and lower, louder and louder and still keep your treble. in practice of course the complexity of the phase lens will quickly start to get out of control so there is some limit in practice.

do you understand ?

a second, optional optimization of the compression driver has to do with diaphragm itself ...