Hemp Acoustics, Tone tubby, and Omega loudspeakers..
Just so nobody thinks that I have a particular bias (OK, I do, I'm Canuck, but all you south of the 49th do too), I invite any of the principals involved to join in the thread. And I am not encouraging bickering regarding who said what to whom, etc. I guess I feel that whatever the "true" story is, it must lie someplace between A said, B said, C said.
I believe the absolute truth may never be known about this situation. I wonder if Hemp is even legal to possess in the good old, US of A? Although I do have an "alignment" with Hemp, I am not encouraging absolute here say, but I would rather have each of the parties involved to actually make a statement regarding these issues. It may help clear the "air".
As per performance, I know that musicians are enjoying Tone Tubbys, And Omega loudspeakers have been well reviewed , regardless of whose drivers are in them. So Gentlemen, if Messieurs Pecker, Harrison, and Chochos would like to make a comment or statement I would invite them to do so.
sit back, relax, and enjoy some tunes tonight. Life can be way too serious.
Just so nobody thinks that I have a particular bias (OK, I do, I'm Canuck, but all you south of the 49th do too), I invite any of the principals involved to join in the thread. And I am not encouraging bickering regarding who said what to whom, etc. I guess I feel that whatever the "true" story is, it must lie someplace between A said, B said, C said.
I believe the absolute truth may never be known about this situation. I wonder if Hemp is even legal to possess in the good old, US of A? Although I do have an "alignment" with Hemp, I am not encouraging absolute here say, but I would rather have each of the parties involved to actually make a statement regarding these issues. It may help clear the "air".
As per performance, I know that musicians are enjoying Tone Tubbys, And Omega loudspeakers have been well reviewed , regardless of whose drivers are in them. So Gentlemen, if Messieurs Pecker, Harrison, and Chochos would like to make a comment or statement I would invite them to do so.
sit back, relax, and enjoy some tunes tonight. Life can be way too serious.
The Hemp8 is used by a friend in a TL and I have helped him with measurements and notch issues. Now he is preparing an MLTQWT with it (notched). To my ears the Hemp has less enough self noise than any Fostex and sounds attractively organic. It loses in sensitivity and half last upper octave energy.
nodiak said:
The damar has smoothed out a little of the harshness, or hotness, or whatever you want to call it, that bothered me. The edge that rode on top of voices was reduced. Kind of like turning down the distortion a notch. I expect it's damping down a breakup mode or two in the whizzer that were in evidence in the 3 - 10 kHz range. It's been effective enough that I've reduced the cut in my makeshift correction circuit, and may back it off another notch this weekend.
Wake up the FR125? I suspect it would pu them all the way into REM! Then again, I LIKE the copper, so YMMV.
Hemptone8
I looked at the A Broun Soun web site and they are now selling an 8" full range driver that that looks like a twin of the Hemp Acoustic FR8.
$128 plus $10 shipping. The plot thickens. James
http://www.abrown.com/home.htm
I looked at the A Broun Soun web site and they are now selling an 8" full range driver that that looks like a twin of the Hemp Acoustic FR8.
$128 plus $10 shipping. The plot thickens. James
http://www.abrown.com/home.htm
Daveis said:
It's just a notch, not a crossover. Its for 1.10mX0.26m (HxW)baffle.
3 components in parallel together, and the whole connected in series to + input. 1mH, 3uF, 10R for heavy damped TL or MLTQWT, or 6R8 for almost undamped TL or BR. Can't foretell results for different baffles causing different diffraction. The R element affects mids spl. The bigger, the less the mids. You can play between 6R8 to 10R (10W) for your particular cab.
Hemptone8
The Broun Soun's FR looks exactly like the one I've got from Hemp, cone, basket and all.
Their 5.25" looks way different though, with stamped basket and much larger magnet.
The FR of 8" FR also looks very close to what I've measured, both peaks including. The only possible difference is the shorting ring in the motor. Broun Soun claims to have it. I'd guess, if Hemp had it - they would not keep it secret. The Le of my Hemp is .65 mH, which most likely for the 8 Ohm driver with modest magnet means no shorting ring.
VadimB
The Broun Soun's FR looks exactly like the one I've got from Hemp, cone, basket and all.
Their 5.25" looks way different though, with stamped basket and much larger magnet.
The FR of 8" FR also looks very close to what I've measured, both peaks including. The only possible difference is the shorting ring in the motor. Broun Soun claims to have it. I'd guess, if Hemp had it - they would not keep it secret. The Le of my Hemp is .65 mH, which most likely for the 8 Ohm driver with modest magnet means no shorting ring.
VadimB
Interesting...
The 5.25 is different. The 6.5 is interesting in that it has very useable bandwidth to ~5-6KHz, and 88db is decent enuff, I suppose. There is your BIB-worthy 6.5" for the moment. I like this driver, very powerful potential here, methinks...
The 8" stacks up abit different from the V1.0 FR8. Shorting ring indeed.
I feel encouraged that John Harrison has seen the light, and has chosen to run with this, his own stuff. These guys are diehard rockers, and our thang is virtually unknown to them, by their own admission. I feel fortunate that I will have the opportunity to encourage him further-----> (6.5" fullranger)
The 5.25 is different. The 6.5 is interesting in that it has very useable bandwidth to ~5-6KHz, and 88db is decent enuff, I suppose. There is your BIB-worthy 6.5" for the moment. I like this driver, very powerful potential here, methinks...
The 8" stacks up abit different from the V1.0 FR8. Shorting ring indeed.
I feel encouraged that John Harrison has seen the light, and has chosen to run with this, his own stuff. These guys are diehard rockers, and our thang is virtually unknown to them, by their own admission. I feel fortunate that I will have the opportunity to encourage him further-----> (6.5" fullranger)
Interesting that the Hemp Acoustics products page only has a note from 18Sep06 that their line up is being updated. James
http://www.hempacoustics.com/products.php
http://www.hempacoustics.com/products.php
dmason said:
If Harrison has a patent, what's the number? I don't believe one exists, only his claim. AFAIK, I can buy the same cones from his supplier, who likely actually came up with the "recipie."
In addition, the 8" FR marketed by Harrison appears to a copy of the Hemp Acoustics design. Louis did suggest changes like the rolled whizzer, but nothing substantial. The motor, suspension, basket etc. all appear identical to the original Hemp Acoustics design. Hemp Acoustics employes engineers, who designed the driver. Harrison is not an engineer is he? Hopefully he will hire one in the future if he intends to sell his own stuff.
James: compare the response of the ABS driver to that of Hemp Acoustics, or for that matter the Fostex 206 to 207. The shorting ring lowers distortion, and keeps the impedance curve flatter up to the upper limit of the driver. This means the frequency response rises much more steeply. With a shorting ring these 8" drivers rise nearly 10db on axis, versus 5db without the shorting ring.
8" drivers with shorting rings should be in proper horns, have treble shelving circuits or both, unless you like really bright speakers (some people do.) Designers like Ted Jordan and Dan Wiggins use the impedance rise in their drivers (no shorting rings) to tame the HF response. On smaller drivers (like the 4" Tang Bands) the HF rise is a little less severe with a shorting ring, so they work in a BR or TL.
The A Brown Sound drivers with a shorting ring will be really bright (no defying physics). At least their published SPL charts don't lie. Again, some folks like that, but not these ears.
Paul
salas said:
Salas,
Scanning back through this thread, I saw that in post #2 I managed to type 0.1 mH instead of 1.0, which is what I'm actually using. No wonder folks thouht I was out in left field! Gotta proofread more carefully, I seem to be getting more dyslexic as I age.
I dropped the resistor from 13R to 9.5R after treating the whizzer with a little damar varnish. I'm amazed that I wound up by SWAG right around were you got by measurement. I think that the ideal for my system right now would be somewhere in between. Maybe increase the size of the inductor a bit, too. I'm sure the bypass cap would help the measured response in the 10k - 20k range, but I don't feel a great need for it.
Do you have any before / after FR plots you could share?
Bill
Audio speaker cone appartus and method of manufacture
Pub #: US2006013433
Date: 2006-01-19
Inventor: HARRISON JOHN G (US)
Regards
James
Pub #: US2006013433
Date: 2006-01-19
Inventor: HARRISON JOHN G (US)
Regards
James
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