Jerry, from what ive seen the "balloon" diaphragms mostly are able to operate well and should contain only the air inside said diaphragm. The shape of the surround is unique and so is its function. it is a very narrow u and is a lot stiffer than most surrounds. I still have to work out the details for construction.
A 'balloon' surround was intimated in the patent...but to be filled with some sort of 'damping fluid'. Might be possible now, but back then....nope. Even now it'd be difficult. Like mating a bicycle tube with an 'O' ring...and flanged....
By 'diaphragm', are you referring to the volume beneath the GP cone? In their 'stand-alone' models, it's not large, and I don't suspect there's any opening(s)....'course, they've elected not to post any pics of the underside either...
By 'diaphragm', are you referring to the volume beneath the GP cone? In their 'stand-alone' models, it's not large, and I don't suspect there's any opening(s)....'course, they've elected not to post any pics of the underside either...
Talkin about balloons, flyin pretty high right now. Didn't have to work this weekend! YeeeHaww!!!
....like I was saying, the next thing he'll post is that he's moving to Colorado and taking up *ahem* 'alternative gardening'....
Sounds like you've started the weekend early... 😉 'Course you know They might have some sinister 'thing' to spring on you Monday. "Rest up, next week is going to be busy..." Makes one want to bug offices and clone phones, spend the weekend vacillating between wild abandon and grinding paranoia....*Evil L*
Sounds like you've started the weekend early... 😉 'Course you know They might have some sinister 'thing' to spring on you Monday. "Rest up, next week is going to be busy..." Makes one want to bug offices and clone phones, spend the weekend vacillating between wild abandon and grinding paranoia....*Evil L*
Yeah, that's what we were all saying when we left work. 🙂
BTW Do you have the actual physical specs for the GP cone?
I scaled it on screen based on their base diameter and get a 5.5" cone with a 1.9" VC. The angle was 73 degrees.
A carbon-fiber/epoxy cone that size would be extraordinarily light-weight at less than 3 grams. It would be about 6.5 mg/cm^2. 😱
*G* Well, y'all may be right....Monday's 'stick' vs. today's 'carrot'. Enjoy the extended weekend....sounds like you've got a 'plot' that's hot to trot... 😉
Ah, #539, Mags states the cone @ 2"vc, 5" dia. base, 5.5" h., angle's 'bout right. Yeah, a cf cone would be the ticket....you considering playing with your carbon sheet material on your 'unexpected holiday'? I don't know enough about the process involved as to how to go about that, but that could be a fun diversion.
My weekend looks like the typical slavery. We're pretty busy, so I haven't had much time for 'creative play'. I'd like to make a pair of paper cones for the mids I salvaged (or would you say 'savaged') from that pair of 3 way speakers I scored from Habitat. One of the tweets is dead, so they're not candidates. The woofs can wait, but they'll likely get the same abuse at some point...
Had a thought about the mids I did for the V3.5's which I corrected and will try to check out this weekend. The structure seemed too tight between base and magnet/vc, perhaps damping the cone excessively. Cheap fix: add some washers. If I blow them up, no great loss.
Ah, #539, Mags states the cone @ 2"vc, 5" dia. base, 5.5" h., angle's 'bout right. Yeah, a cf cone would be the ticket....you considering playing with your carbon sheet material on your 'unexpected holiday'? I don't know enough about the process involved as to how to go about that, but that could be a fun diversion.
My weekend looks like the typical slavery. We're pretty busy, so I haven't had much time for 'creative play'. I'd like to make a pair of paper cones for the mids I salvaged (or would you say 'savaged') from that pair of 3 way speakers I scored from Habitat. One of the tweets is dead, so they're not candidates. The woofs can wait, but they'll likely get the same abuse at some point...
Had a thought about the mids I did for the V3.5's which I corrected and will try to check out this weekend. The structure seemed too tight between base and magnet/vc, perhaps damping the cone excessively. Cheap fix: add some washers. If I blow them up, no great loss.
I made a couple drivers last week. one is a carbon/paper lam weighing in at a hefty 3.41 g. The other, a cotton vellum at 1.41 g. The paper cone has slightly better highs, the carbon/paper lam handles wattage without breaking a sweat. Both sound nice with an enclosure. You don't need a "woofer", unless your a bass freak. In that case...add a sub.
Thinking about an easy way to measure impulse propagation velocity. I can then tweek the cone angle. I think that will improve perceived high freq output (coherency), although it's already good.
Thinking about an easy way to measure impulse propagation velocity. I can then tweek the cone angle. I think that will improve perceived high freq output (coherency), although it's already good.
Attachments
Here's a pic of the paper cone. the paper is clearprint cotton vellum (.076mm) at 64g/m^2. Nice highs. Cone fails at high driving levels though. When making a driver, assembling everything in perfect alignment is the key to success. There was a small imperfection where the cone base connects to the surround.
Attachments
Nice looking pair ya got there. 😉 (Nice to be able to say that without getting slapped *L*)
Alignment is definitely important to attend to. I've made it standard procedure to shim the vc before gluing the cone to keep it centered, and to ensure the base of the cone is centered on the surround since I've been 'rolling my own' with the EVA foam...
"Impulse propagation velocity"...now that's a parameter that will be interesting to hear how you intend to quantify that. It brings to mind bouncing a laser off the cone to some sort of sensor, but that doesn't sound like the usual gadget one finds in a normal shop. But since I've no clue as to what you've got on your workbench, I maybe shouldn't be too quick to assume....*G*
Per the patent, the velocity of an impulse descending the cone was stated as being the speed of sound, 1,126 ft./s. How much any given material would effect that would be interesting to know, but would seem to be somewhat daunting to quantify in a diy fashion....IMHO. But don't let my skepticism stand in the way. If HP and Apple can start in a garage, you can measure IPV @ home.
But if I hear next week that somebody invented warp drive in their bathroom, I'm out. *L* Reality would have become way too warped for even yours truly to comprehend, much less carry on in...
Anywho, back to your observations of cf/paper vs. vellum...it does make sense that the cf/p would be able to 'play harder', likely due to density. The vellum, being less dense and lighter would be able to 'go higher'. Pity it breaks up...do you think the imperfection can be repaired?
They look like 4" dia. units...I wouldn't expect huge bass from them, either. And as for the need for more bass, a sub is my weapon of choice even with my 6's. And they've got the surface area of a 8" dia. typ. speaker, roughly. It just 'rounds them out' for general listening. Since they've broken in, they can handle being turned up a bit although I still try to be conservative with the volume control. Having 4 of them running, creating a 'field' seems to make up for higher volume, ultimately. It's immersive, and really rather addictive. I've not used my 'regular' speaker stacks for quite awhile....haven't felt the need to. Haven't needed to try to knock the dust off the walls, either. *L*
In any case, it sounds like you're enjoying your 'extended weekend'....do carry on...😉
Alignment is definitely important to attend to. I've made it standard procedure to shim the vc before gluing the cone to keep it centered, and to ensure the base of the cone is centered on the surround since I've been 'rolling my own' with the EVA foam...
"Impulse propagation velocity"...now that's a parameter that will be interesting to hear how you intend to quantify that. It brings to mind bouncing a laser off the cone to some sort of sensor, but that doesn't sound like the usual gadget one finds in a normal shop. But since I've no clue as to what you've got on your workbench, I maybe shouldn't be too quick to assume....*G*
Per the patent, the velocity of an impulse descending the cone was stated as being the speed of sound, 1,126 ft./s. How much any given material would effect that would be interesting to know, but would seem to be somewhat daunting to quantify in a diy fashion....IMHO. But don't let my skepticism stand in the way. If HP and Apple can start in a garage, you can measure IPV @ home.
But if I hear next week that somebody invented warp drive in their bathroom, I'm out. *L* Reality would have become way too warped for even yours truly to comprehend, much less carry on in...
Anywho, back to your observations of cf/paper vs. vellum...it does make sense that the cf/p would be able to 'play harder', likely due to density. The vellum, being less dense and lighter would be able to 'go higher'. Pity it breaks up...do you think the imperfection can be repaired?
They look like 4" dia. units...I wouldn't expect huge bass from them, either. And as for the need for more bass, a sub is my weapon of choice even with my 6's. And they've got the surface area of a 8" dia. typ. speaker, roughly. It just 'rounds them out' for general listening. Since they've broken in, they can handle being turned up a bit although I still try to be conservative with the volume control. Having 4 of them running, creating a 'field' seems to make up for higher volume, ultimately. It's immersive, and really rather addictive. I've not used my 'regular' speaker stacks for quite awhile....haven't felt the need to. Haven't needed to try to knock the dust off the walls, either. *L*
In any case, it sounds like you're enjoying your 'extended weekend'....do carry on...😉
...and I won't assume why you've got a gram scale....but musicians sometimes need that sort of paraphernalia...makes sense to this refugee from the '60's....
The cone velocity must be greater than (supersonic). This page explains why...Evanescent Waves (sound radiation from a plate)
The bending wave velocity is proportional to the square root of frequency, so it slows at lower frequency.
My carbon/paper laminate has way different stiffness properties than plain paper, and is able to handle higher stress loads. A curve-linear cone shape would greatly improve the mechanical integrity, and also disperse slower waves at a more appropriate angle. At higher driving forces the straight-sided paper cones can be effected by standing waves fairly easily.
The small 95mm cones actually have a respectable bass output if coupled with an enclosure. Mine are on a couple different types of transmission lines.
I have no measurements to offer, but I do EQ some of the bass out.🙂
Darkroom, photo lab...OK, check. *G* One needs that sort of thing in their personal 'red light district'. 😉 Just kidding...
And a curve-linear cone shape would be a feat to diy....so we're kinda stuck with the typ straight side cone config.... One could cast that shape with paper pulp and the appropo equipment, but that would be an advanced sort of experiment. Interesting to consider, though...
Yeah, I know you like to couple yours to bases to utilize the back wave from the cone, where I ignore mine. Perhaps this winter I may play about with the PVC bases that I'm using to support them to see what's possible.
Meanwhile, it's starting to look like a serious Cone Collective around here. I've got 5 pairs up and running, and two potential pairs and two singles (both Bose drivers, a gift from my commercial 'neighbor') up for renovation....
Time for more a 'serious' wiring experiment....I have this Plan...
And a curve-linear cone shape would be a feat to diy....so we're kinda stuck with the typ straight side cone config.... One could cast that shape with paper pulp and the appropo equipment, but that would be an advanced sort of experiment. Interesting to consider, though...
Yeah, I know you like to couple yours to bases to utilize the back wave from the cone, where I ignore mine. Perhaps this winter I may play about with the PVC bases that I'm using to support them to see what's possible.
Meanwhile, it's starting to look like a serious Cone Collective around here. I've got 5 pairs up and running, and two potential pairs and two singles (both Bose drivers, a gift from my commercial 'neighbor') up for renovation....
Time for more a 'serious' wiring experiment....I have this Plan...
Fun find, online...Equalizer APO with the Peace GUI. 1/3 octaves if you need that sort of audio razor. Makes the array a bit happier to play loud without making the vc's complaining. A curious 'db pumping' unless one dials in a tad of delay...I wonder if it's the CPU stuttering about trying to keep up in RT. Makes me consider running a pair of 'puters and spreading out the chores, source in A, processing in B.
*L*mock sigh* Just another project...😉
Meanwhile....we're wrestling with bears....I'm not kidding...
*L*mock sigh* Just another project...😉
Meanwhile....we're wrestling with bears....I'm not kidding...
I know its not to me but I use mine to mix my own supplements. also I am able to get darn perfect epoxy ratios.
I think the process for the cone is very simple and pretty good to get an accurate cone. Now this is pretty basic I will expand latter on what I actually mean with some things and why.
Materials : Mirror, 2.9oz plain carbon, Epoxy, vacuum pump/press, scissor, template, spray adhesive, glue, sand paper.
Process: lay mirror on table, spread a base of epoxy, lay carbon, spread epoxy, vacuum-bag, or lay a releasable weight on top to firmly press, make a cutout template with cad and spray re-positionable adhesive then lay the template on the carbon. cut out with the scissors. sand edges to make up for cuts. remove template, roll to the proper shape and glue the ends, then do what ever treatment then proceed to glue to terminations.
Materials : Mirror, 2.9oz plain carbon, Epoxy, vacuum pump/press, scissor, template, spray adhesive, glue, sand paper.
Process: lay mirror on table, spread a base of epoxy, lay carbon, spread epoxy, vacuum-bag, or lay a releasable weight on top to firmly press, make a cutout template with cad and spray re-positionable adhesive then lay the template on the carbon. cut out with the scissors. sand edges to make up for cuts. remove template, roll to the proper shape and glue the ends, then do what ever treatment then proceed to glue to terminations.
Yes, I've had no problems making cones that are as accurate as I can draw and cut with scissors (using a template).
I made a sample with carbon/epoxy, and it is very robust. But, it is also relatively heavy, that's my concern.
I did find a place in the UK that sells super light bi-axial here: Carboline SC26/2/45 Spread Carbon Fabric +/- 45° 26g/m² - Carbon Materials