Graham Maynard said:
Sigh.... that's the problem, isn't it?
I don't notice it at all in daily life or listening to live music. But for critical listening, yeah. 🙁
Here is a link to the LED strobe software
Strobe Sync Pulse Generator
The idea with a laser to reflect the coherent lights waves back onto themselves thus creating an interference pattern. I don't know how well this would work for black speaker cones. 😉
The Strobe may allow direct viewing of cone in action, freeze frame. I don't know if or how you would photograph or video tape this.
This is shareware, with a free trial period. I have yet to try it, though I have plenty of amps and LEDs.
A word of warning: Be sure to use ballast resistors on the LED(s) for protection of your amp and the LEDs. A few 100 ohms should do.
If you don't have a good local source for LEDs, I buy from this guy on eBay. He always has plenty of stock and great prices.
LED Store
Strobe Sync Pulse Generator
The idea with a laser to reflect the coherent lights waves back onto themselves thus creating an interference pattern. I don't know how well this would work for black speaker cones. 😉
The Strobe may allow direct viewing of cone in action, freeze frame. I don't know if or how you would photograph or video tape this.
This is shareware, with a free trial period. I have yet to try it, though I have plenty of amps and LEDs.
A word of warning: Be sure to use ballast resistors on the LED(s) for protection of your amp and the LEDs. A few 100 ohms should do.
If you don't have a good local source for LEDs, I buy from this guy on eBay. He always has plenty of stock and great prices.
LED Store
planet10 said:
John; there are folks following this thread who will be convene for the listening portion of Dave's scheduled test regimen.
As much as all of us here enjoy a civilized and well intentioned debate, in the hope of avoiding any argument over the results of these listening tests, could you describe the methodology that you would consider acceptable?
I'd suggest there is no consensus amongst DIYers as to what constitutes a "valid objective" comparative listening test. I for one have a short attention span, and simply want to get on with enjoying the music, - and after a few switches back and forth just want to sit back and listen, without drawn out analytic discussion with the rest of the "panel" .
There will be at least 3 pairs of identical speaker enclosures available (or as close to sonically identical as can be fabricated by hand), and a range of amplifiers available that have previously been identified as compatible with the drivers in question. Now, the matter of individual preference for the synergy (or lack) of the electronics' and speaker systems' sonic signatures is an entirely different can of worms. I trust you will allow that regardless of the sophistication of objective test equipment and data analysis available, there is as of yet no metric to explain any individual listener's "taste"?
I Have a 600 joule strobe that can generate very narrow pulsewidths on low power. As little as 1/10,000 of a second on minimum power.
As long as the strobe pulse is brighter than the total ambient light accululated over the time the shutter is open you don't need a high shutter speed.
Photographing parts of a speaker cone while in motion wouldn't be too hard, Just a bit time comsuming to set up.
We would need to generate repeatable cone breakup from a repeatable signal, and trigger the camera at the same time, probably from a rectified tone from the right channel while audio signal is out the left. As long as the apparatus doesn't change (full camera battery etc etc) we should be able to get repeatable resilts. Using the same sound sample and offsetting the trigger pulse we can get several shots to look at the breakup in various stages. It'll take me some time to devise the shutter release because my camera has an infra red remote.
I suggest looking closely at a portion of the driver from a 45 degree angle from one side, something right in front may skew the results.
Tell me how to generate a breakup, where to point the camera and I'll give it a go. I'll have the time to spend a few days on it in a couple of weeks.
My drivers are Fe207E with phase plugs. No cone treatments, about 200-400 hours on them.
As long as the strobe pulse is brighter than the total ambient light accululated over the time the shutter is open you don't need a high shutter speed.
Photographing parts of a speaker cone while in motion wouldn't be too hard, Just a bit time comsuming to set up.
We would need to generate repeatable cone breakup from a repeatable signal, and trigger the camera at the same time, probably from a rectified tone from the right channel while audio signal is out the left. As long as the apparatus doesn't change (full camera battery etc etc) we should be able to get repeatable resilts. Using the same sound sample and offsetting the trigger pulse we can get several shots to look at the breakup in various stages. It'll take me some time to devise the shutter release because my camera has an infra red remote.
I suggest looking closely at a portion of the driver from a 45 degree angle from one side, something right in front may skew the results.
Tell me how to generate a breakup, where to point the camera and I'll give it a go. I'll have the time to spend a few days on it in a couple of weeks.
My drivers are Fe207E with phase plugs. No cone treatments, about 200-400 hours on them.
chrisb said:
Chris,
My preference would be to see the test equipment setup by a person who will not attend the listening. Only he would know which speaker was which.
The listener would have a known piece of music selected and the ability to switch (by remote control) between speakers. He would be completely ignorant of which speaker was treated. He would also be alone in the room, free of outside influence and distractions.
Once judged, he would write down his findings and put it in a ballot box.
The test could continue with as many judges as desired, following the same procedure.
An attempt should be made to redo the test again at a later time, perhaps the next day, with the speakers switched. The purpose of this would be to put the set of speaker on top (I assume one on top of the other is the best arrangement) to the lower position.
Oh, and using the same judges.
All speaker cables and interconnects should be the same length and type (not that I think that makes a difference).
In the end, you tabulate the results from the ballot box.
Finally, the amp can be any suitable one, my preference would be a Yamaha HT receiver, but you all can't afford one of those😉
drivers offered into the fray, again
planet_10,
The drivers I so embarassingly gushed over are once again offered for this test if it is deemed useful. Bud applied the treatment.
Richard
planet_10,
The drivers I so embarassingly gushed over are once again offered for this test if it is deemed useful. Bud applied the treatment.
Richard
Planet 10,
Dave, would you please contact the "back room " and ask for their input on this test regimen? It would be their particular specialty and I am fairly sure I have seen comments in other threads about how to set up one of these tests.
John,
Were you offering to provide your Yamaha, perhaps so it could also be blind tested?
Richard,
I do not see anything in your post that indicates gushing. I would like to see your opinions, at some later date, after the new wears off and you begin to pick things apart.
Your offer of the prized pair is quite generous. It would be good if you could be one of the participants, having not heard an untreated hemp cone. Not as a voting participant, but as a control.
Bud
Dave, would you please contact the "back room " and ask for their input on this test regimen? It would be their particular specialty and I am fairly sure I have seen comments in other threads about how to set up one of these tests.
John,
Were you offering to provide your Yamaha, perhaps so it could also be blind tested?
Richard,
I do not see anything in your post that indicates gushing. I would like to see your opinions, at some later date, after the new wears off and you begin to pick things apart.
Your offer of the prized pair is quite generous. It would be good if you could be one of the participants, having not heard an untreated hemp cone. Not as a voting participant, but as a control.
Bud
BudP said:
I will be happy to report ongoing sound as long as what I hear with my feeble ears, in my disheveled living room, with my pseudo-rig, is wanted by anyone. It would be my pleasure to participate in any way...🙂
OzMikeH and Panomaniac,
Here is a link to some video's provided on U Tube. The items of interest are the Resonance videos
http://youtube.com/user/shermph
Some other somewhat less educational videos are here.
http://youtube.com/watch?v=Zkox6niJ1Wc
I am not suggesting that you need to duplicate any of this. This is just for background visual information, on what breakup looks like, on a way out of scale demonstration.
There is a section in Baranek's Acoustics on tests similar to what you are suggesting , done in the 50's. I have reprinted them in the often pointed to paper over on positive feedback online. The tests were not performed by Baranek and a reading of the chapter he presents them in is rather eye opening.
Bud
Here is a link to some video's provided on U Tube. The items of interest are the Resonance videos
http://youtube.com/user/shermph
Some other somewhat less educational videos are here.
http://youtube.com/watch?v=Zkox6niJ1Wc
I am not suggesting that you need to duplicate any of this. This is just for background visual information, on what breakup looks like, on a way out of scale demonstration.
There is a section in Baranek's Acoustics on tests similar to what you are suggesting , done in the 50's. I have reprinted them in the often pointed to paper over on positive feedback online. The tests were not performed by Baranek and a reading of the chapter he presents them in is rather eye opening.
Bud
Re: JX92S
I actually have not much experience with the JX92S, they were purchased over a year ago for a design that has not yet realized. I'll mail you, but if the subject is related with the EnABL process, let's try and keep it in this thread.
t-head,t-head said:
I actually have not much experience with the JX92S, they were purchased over a year ago for a design that has not yet realized. I'll mail you, but if the subject is related with the EnABL process, let's try and keep it in this thread.
BudP said:
Bud, the Yamaha has to stay here. A full days work just to disconnect it.
Besides, blind test against what? One of Dave's dumpster diving expedition tube amps?
No, a pair of 110 watt push pull triode, all transformer coupled, El 34 mono blocks with a tube preamp to boot. Should be roughly the same power level and certainly the Yamaha should have no trouble dusting off such ancient technology, utilizing such obviously compromised devices as transformers, don't you think?
Bud
Oh, the old tube vs. solid state debate. You don't want to go down that road here, do you?
As far as transformers go, you are one up on me there. If you don't have a problem with the distortion inherent in a tube amp, the non-linear behavior of an output transformer shouldn't trouble you.
Not my cup of tea though.
As far as transformers go, you are one up on me there. If you don't have a problem with the distortion inherent in a tube amp, the non-linear behavior of an output transformer shouldn't trouble you.
Not my cup of tea though.
Re: Re: JX92S
soongsc,
As all seem to be finally getting along and playing nice, I did not wish to change subjects. But now that I have your attention, I need the measurement for location of 'middle' ring which BudP thought had to be critical (within .5mm) for treating driver specific distortion. You tried a pattern with toothpaste, posted a pic that we can't measure due to lack of scale in pic. I need help if you are so inclined. Thanks. I may have passed the prob. period...
Richard
soongsc said:
soongsc,
As all seem to be finally getting along and playing nice, I did not wish to change subjects. But now that I have your attention, I need the measurement for location of 'middle' ring which BudP thought had to be critical (within .5mm) for treating driver specific distortion. You tried a pattern with toothpaste, posted a pic that we can't measure due to lack of scale in pic. I need help if you are so inclined. Thanks. I may have passed the prob. period...
Richard
Re: Re: Re: JX92S
The middle pattern outer ring outer edge is at 65mm diameter, the outer edge of the inner ring is at 60.5mm diameter. You might want to use toothpaste first until you have optimum location. Please let us know what you measure and/or what you hear. Mine are still sitting in there waiting for someone here that use these drivers to compare with. In case you use toothpaste, the kind that dries instead of remaining tacky, it's quite easy to use something like a peice of overhead presentation transparency slide to scoop it off, final cleanup can be done with a damp cotton swab.
t-head said:
The middle pattern outer ring outer edge is at 65mm diameter, the outer edge of the inner ring is at 60.5mm diameter. You might want to use toothpaste first until you have optimum location. Please let us know what you measure and/or what you hear. Mine are still sitting in there waiting for someone here that use these drivers to compare with. In case you use toothpaste, the kind that dries instead of remaining tacky, it's quite easy to use something like a peice of overhead presentation transparency slide to scoop it off, final cleanup can be done with a damp cotton swab.
John,
As far as I am concerned, at the level of performance our amplifiers are at, there would be very little to chose from in audible performance, in a carefully controlled blind listening test.
Measurements are another thing entirely, though my transformers are extremely linear devices, with extremely low distortion. Remaining phase and frequency flat, at full power, up tp 35 and 45 kHz respectively, and above 250 Hz, with distortion commensurate with transistors in direct drive mode. A lack of zero crossing distortion in push pull and a lack of hysteresis in SE helps.
Really neither of us has the best compromise. Without question the best sounding, lowest distortion by measurement amplifier I have run across is a little 20 watt push pull all solid state amp, built by Gary Pimm. Constant current source input splitter and fully differential from there on. Using interstage transformers and the same OPT's as are in Lynn Olson's push pull DHT amplifier, the Karna. Which is only in second place because it is not yet a stable device.
Gary runs his solid state drivers at tube vac levels, 120 volts or more. Uses the OPT's lack of hysteresis and flat phase response to put out a remarkable sound. Absolutely no fatigue, no errant sounds regardless of the drive source, and a musical presentation to weep over. Trust me here please, if you heard it you would have to have one. Not to replace the Yamaha with, but you would find a way to use it, often.
Now, if we could just get him back off of his audio for others sabbatical, he was making noises of 70 watts and beyond......
I was actually trying to lure your Yamaha out to the testing grounds so that you would no longer have to take heat for liking it, from your fellow countrymen. I realize you are combative enough to not care, but still.
Bud
As far as I am concerned, at the level of performance our amplifiers are at, there would be very little to chose from in audible performance, in a carefully controlled blind listening test.
Measurements are another thing entirely, though my transformers are extremely linear devices, with extremely low distortion. Remaining phase and frequency flat, at full power, up tp 35 and 45 kHz respectively, and above 250 Hz, with distortion commensurate with transistors in direct drive mode. A lack of zero crossing distortion in push pull and a lack of hysteresis in SE helps.
Really neither of us has the best compromise. Without question the best sounding, lowest distortion by measurement amplifier I have run across is a little 20 watt push pull all solid state amp, built by Gary Pimm. Constant current source input splitter and fully differential from there on. Using interstage transformers and the same OPT's as are in Lynn Olson's push pull DHT amplifier, the Karna. Which is only in second place because it is not yet a stable device.
Gary runs his solid state drivers at tube vac levels, 120 volts or more. Uses the OPT's lack of hysteresis and flat phase response to put out a remarkable sound. Absolutely no fatigue, no errant sounds regardless of the drive source, and a musical presentation to weep over. Trust me here please, if you heard it you would have to have one. Not to replace the Yamaha with, but you would find a way to use it, often.
Now, if we could just get him back off of his audio for others sabbatical, he was making noises of 70 watts and beyond......
I was actually trying to lure your Yamaha out to the testing grounds so that you would no longer have to take heat for liking it, from your fellow countrymen. I realize you are combative enough to not care, but still.
Bud
Hi Bud,
Regarding the testing of your EnABL pattern with frequency response tools may not be the correct methodology to study what is happening to the sound wave traveling along the surface of the speaker cone (or other treated materials such as speaker baffles).
I have never been under the impression that your EnABL pattern blocks were intended to directly enhance the frequency response characteristics of the treated material - but were instead designed with the intention of blocking (or reducing to a great extent) the waves being reflected from the speaker surround or other boundaries. In our initial discussions (back in the old Mamboni Walsh 5 Remake thread) we discussed wave theory and reflections that happen in water tanks, the resulting interference with the incoming wave, and what affect your EnABL pattern (and others) would provide to reduce the reflected wave.
As we know because we are either 1) audio nuts or 2) surfers or 3) sailors - waves by their nature are comprised of frequency, duration, amplitude and relative density of materials involved (this has been noticed by "soongsc" and his test using metal cones). BTW - very nice work there for a 1st generation test process. As noted by John there could be some improvements made in the scientific method used but perhaps that will come with time, some constructive feedback, and a "target", or definition of just what in the h*** are we rally looking for and what is the best method (or methods) of study and test? There are some other considerations about cone materials and construction but discussing those serves little if any purpose at this time and place - perhaps later.
The point I'm getting to is that if the intention of the EnABL pattern is to attenuate the reflected wave (by whatever means) then a test you might consider is using a single pulse with which to excite the speaker cone - corresponding to a single wave in a water tank - and look at the wave being reflected from the speaker surround. The use of a pulse or function generator would be useful for this type of test. Short duration tone bust at different frequencies and amplitude would be useful and might help in the selection of block size and pattern for various cone sizes and materials used to attenuate reflected waves.
IMO RTA's (Real Time Analyzers), waterfall plots, frequency response charts etc. are not going to directly show you what is going on with EnABL. I think you need to be looking at what is NOT going on - and that would be the reflected wave interfering with the primary wave. Using these tools might show you a "cleaner" signal from the speaker- but that is a secondary result of attenuating the reflection by using your pattern.
Just some thoughts that I hope you may find helpful.
Regarding the testing of your EnABL pattern with frequency response tools may not be the correct methodology to study what is happening to the sound wave traveling along the surface of the speaker cone (or other treated materials such as speaker baffles).
I have never been under the impression that your EnABL pattern blocks were intended to directly enhance the frequency response characteristics of the treated material - but were instead designed with the intention of blocking (or reducing to a great extent) the waves being reflected from the speaker surround or other boundaries. In our initial discussions (back in the old Mamboni Walsh 5 Remake thread) we discussed wave theory and reflections that happen in water tanks, the resulting interference with the incoming wave, and what affect your EnABL pattern (and others) would provide to reduce the reflected wave.
As we know because we are either 1) audio nuts or 2) surfers or 3) sailors - waves by their nature are comprised of frequency, duration, amplitude and relative density of materials involved (this has been noticed by "soongsc" and his test using metal cones). BTW - very nice work there for a 1st generation test process. As noted by John there could be some improvements made in the scientific method used but perhaps that will come with time, some constructive feedback, and a "target", or definition of just what in the h*** are we rally looking for and what is the best method (or methods) of study and test? There are some other considerations about cone materials and construction but discussing those serves little if any purpose at this time and place - perhaps later.
The point I'm getting to is that if the intention of the EnABL pattern is to attenuate the reflected wave (by whatever means) then a test you might consider is using a single pulse with which to excite the speaker cone - corresponding to a single wave in a water tank - and look at the wave being reflected from the speaker surround. The use of a pulse or function generator would be useful for this type of test. Short duration tone bust at different frequencies and amplitude would be useful and might help in the selection of block size and pattern for various cone sizes and materials used to attenuate reflected waves.
IMO RTA's (Real Time Analyzers), waterfall plots, frequency response charts etc. are not going to directly show you what is going on with EnABL. I think you need to be looking at what is NOT going on - and that would be the reflected wave interfering with the primary wave. Using these tools might show you a "cleaner" signal from the speaker- but that is a secondary result of attenuating the reflection by using your pattern.
Just some thoughts that I hope you may find helpful.
PDAN,
Now that is a creative way to do this stuff. If, indeed, what is needed is a perturbation of the boundary layer, sticking tape into it is going to accomplish the needed act.
What a novel plan, and that it makes a satisfactory change is extremely neat, just as I would expect it to look, neat.
Can you provide a picture or two? I am quite interested in what this driver looks like, just in general and in particular the whizzer cone treatment.
Nice,
Bud
Now that is a creative way to do this stuff. If, indeed, what is needed is a perturbation of the boundary layer, sticking tape into it is going to accomplish the needed act.
What a novel plan, and that it makes a satisfactory change is extremely neat, just as I would expect it to look, neat.
Can you provide a picture or two? I am quite interested in what this driver looks like, just in general and in particular the whizzer cone treatment.
Nice,
Bud
C2C,
Good to see your thinking again. I find it refreshing to think back, in the day, about the Walsh/Mamboni explorations. It has gotten so much more serious since then.
Do you have any thoughts about what sort of apparatus might allow us to capture a moving picture of the area around the EnABL patterns?
The laser interferometer I saw used gave some interesting, spiky, representations of what was happening with the dome. I don't remember seeing the tripart fan of energy exiting the pattern block openings, as is shown when you make a crude pattern on the ripple tank simulator program at http://www.falstad.com/ripple/
The differences in dome surface were noticeable, but I could not interpret them, except that there were no big spikes of displayed energy on the EnABL'd dome representation.
In my own mind, when I try to "see" what would be needed I get a picture of many blue white beams playing over the surface, moving in an interlaced pattern with the reflected light being analyzed for position and specular content and transformed into a moving picture by software. Got any idea what the heck my brain is so frantically signaling about?
Bud
Good to see your thinking again. I find it refreshing to think back, in the day, about the Walsh/Mamboni explorations. It has gotten so much more serious since then.
Do you have any thoughts about what sort of apparatus might allow us to capture a moving picture of the area around the EnABL patterns?
The laser interferometer I saw used gave some interesting, spiky, representations of what was happening with the dome. I don't remember seeing the tripart fan of energy exiting the pattern block openings, as is shown when you make a crude pattern on the ripple tank simulator program at http://www.falstad.com/ripple/
The differences in dome surface were noticeable, but I could not interpret them, except that there were no big spikes of displayed energy on the EnABL'd dome representation.
In my own mind, when I try to "see" what would be needed I get a picture of many blue white beams playing over the surface, moving in an interlaced pattern with the reflected light being analyzed for position and specular content and transformed into a moving picture by software. Got any idea what the heck my brain is so frantically signaling about?
Bud
What's this ?
Blind testing ......?
This is just being at the beck 'n call of the reactionary rabble ........
Dancing to their tune .... a ludicrous rooster strut!
Can't wait for the white smoke.
At least from my ivory tower, this display of bigdickery has been a small entertainment and diversion.
Keep it up chaps !
Cilla
Blind testing ......?
This is just being at the beck 'n call of the reactionary rabble ........
Dancing to their tune .... a ludicrous rooster strut!
Can't wait for the white smoke.
At least from my ivory tower, this display of bigdickery has been a small entertainment and diversion.
Keep it up chaps !
Cilla
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