Thanks!!
Do you think that using that using thicker stuff will account for the same results in your measurements of a thicker materials.
As I have mentioned before I can hear a difference between the two coatings, But, it was very slight and only really noticeable in a side by side A & B test of otherwise (except for the coating) two identical panels.
In fact my last panel that I had burned up had the original Licron coating on it from 2003 and I didn't realize this until I had disassembled it after it burned.
jer
Do you think that using that using thicker stuff will account for the same results in your measurements of a thicker materials.
As I have mentioned before I can hear a difference between the two coatings, But, it was very slight and only really noticeable in a side by side A & B test of otherwise (except for the coating) two identical panels.
In fact my last panel that I had burned up had the original Licron coating on it from 2003 and I didn't realize this until I had disassembled it after it burned.
jer
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I'm not sure exactly what you are asking, but the HF response roll off is due the combined mass of the diaphragm and coating.
It doesn't matter what % of the mass comes from where.
If that did answer your question, can you please restate it?
Most likely any slight differences you heard between the coatings were due to a minor difference in sensitivity between the two panels. Even when run from the same HV supply, seemingly identical panels can differ in output by +/-0.5dB or more. Our ears can easily pick up on this small difference in output level and for whatever reason our brains always seem to prefer the sound of the slightly louder one.
Yes, I don't know what the mass of the coatings are as I figured that this would be the determining factor.
Although I didn't have a measuring microphone at the time I had done the test, I did match up the levels the best I could.
Actually, I think I did just swap out the panels.
What I did notice was that the Crystal coating seemed to have a bit more detail and resiliency of the higher end, But not enough to make a difference of which one to use or not to use.
The difference (although only very slight) was like the difference of sound between a polished cymbal vs an un-polished cymbal but not quite as severe.
I heard this same difference when I originally cleaned the diaphragm removing the extra mass of the dirt and salt that they were coated with from the 7 years of environmental abuse that I put them through when I first fired them back up in 2010.
Only it was much more subtle then the two examples above.
I will try to do a more exacting test of this once I get it back running again, now that I have a measurement microphone.
jer
Although I didn't have a measuring microphone at the time I had done the test, I did match up the levels the best I could.
Actually, I think I did just swap out the panels.
What I did notice was that the Crystal coating seemed to have a bit more detail and resiliency of the higher end, But not enough to make a difference of which one to use or not to use.
The difference (although only very slight) was like the difference of sound between a polished cymbal vs an un-polished cymbal but not quite as severe.
I heard this same difference when I originally cleaned the diaphragm removing the extra mass of the dirt and salt that they were coated with from the 7 years of environmental abuse that I put them through when I first fired them back up in 2010.
Only it was much more subtle then the two examples above.
I will try to do a more exacting test of this once I get it back running again, now that I have a measurement microphone.
jer
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Hi,
it's imho relatively easy to hear differences between 12um and 6um -or thinner- membranes. It is imho also possible to distinguish between a thick sluggish coating like MethylCellulose, Nylon or the old grey Licron and a very thin coating.
It is simply the weight difference which may also be verified by freq response measurements. But as weight differences become small, it becomes more and more difficult to achieve reliable measurements.
Non-homogenous coating may result in uneven SPL over the membrane area.
Non-homogenous mechanical tension may lead to differences.
Flat, non-segmented panels may exhibit extreme directionality.
All this and some more are sources of variations of the output, which may spoil a measuremental verification.
Lastly, the hearing itself -as reliable it may be qualitatively- is very unreliable quantitatively.
For example: typical coatings allow for a charge-up within a few seconds. So after a minute of play nothing should change any more sonically. But there are many reports and claims that the sonic character becomes more vivid, fluid, natural after a couple of hours of charging and playing. And I admit, that I experience that effect regularly when listening to panels which had a longer storage time without charging. Is that a proof of the adaptive capabilities of our hearing, or is there another effect responsible, maybe of mechanical and/or of electrical source?
Iirc a couple of years earlier we had a similar discussion already in a long gone thread. One thought was, that when the weight and the thickness of the coating closed in -or became a significant fraction of- the diaphragms values, certain parameters like e-module, damping, speed of sound, etc. could or must change significantely too. How this translates into quantitave values or qualitative values wasn't discussed further iirc.
But due to the outstanding qualitative qualities of our hearing I'd guess the answer is 42.
jauu
Calvin
it's imho relatively easy to hear differences between 12um and 6um -or thinner- membranes. It is imho also possible to distinguish between a thick sluggish coating like MethylCellulose, Nylon or the old grey Licron and a very thin coating.
It is simply the weight difference which may also be verified by freq response measurements. But as weight differences become small, it becomes more and more difficult to achieve reliable measurements.
Non-homogenous coating may result in uneven SPL over the membrane area.
Non-homogenous mechanical tension may lead to differences.
Flat, non-segmented panels may exhibit extreme directionality.
All this and some more are sources of variations of the output, which may spoil a measuremental verification.
Lastly, the hearing itself -as reliable it may be qualitatively- is very unreliable quantitatively.
For example: typical coatings allow for a charge-up within a few seconds. So after a minute of play nothing should change any more sonically. But there are many reports and claims that the sonic character becomes more vivid, fluid, natural after a couple of hours of charging and playing. And I admit, that I experience that effect regularly when listening to panels which had a longer storage time without charging. Is that a proof of the adaptive capabilities of our hearing, or is there another effect responsible, maybe of mechanical and/or of electrical source?
Iirc a couple of years earlier we had a similar discussion already in a long gone thread. One thought was, that when the weight and the thickness of the coating closed in -or became a significant fraction of- the diaphragms values, certain parameters like e-module, damping, speed of sound, etc. could or must change significantely too. How this translates into quantitave values or qualitative values wasn't discussed further iirc.
But due to the outstanding qualitative qualities of our hearing I'd guess the answer is 42.
jauu
Calvin
This comment reminded me of something in the 1989 Ross Walker interview I recently reread:
One Thing Audio/Manufacturers/Quad/History/Peter Walker
excerpt...
"We stretch it up to the required tension and stick it in the oven. In its cold form, if you stretch it, it will creep. But by putting it in the oven under tension all the molecules will line up to the most stable position so the tension won't change. This is quite important because otherwise the resonance of the speaker would change and it is carefully designed to a particular value. If it was too slack it would hit the plates, too tight the resonance would be too high. Secret ingredient X is used as a damping layer on the Mylar and then we bond the frame to the electrode structure."
Notice he mentions applying ingredient X to the Mylar as a damping layer in the ESL-63. I know they use a mesh cloth glued to on of the stators for damping the diaphragm resonance modes, but this seems to be describing something different. One would think anything capable of providing some damping would add a substantial amount of mass as well.
Anybody familiar with Quads know anything about a damping layer applied to the diaphragm?
Hi,
well, I can see Mr. Walker´s twinkling eye in every second answer ;-)
Just a couple of lines later we learn that secret ingredient X certainly is no ham sandwich *rotfl*
In other words....if there´s any secret and damping ingredient X at all, it will be the conductive coating of the diaphragm.
jauu
Calvin
well, I can see Mr. Walker´s twinkling eye in every second answer ;-)
Just a couple of lines later we learn that secret ingredient X certainly is no ham sandwich *rotfl*
In other words....if there´s any secret and damping ingredient X at all, it will be the conductive coating of the diaphragm.
jauu
Calvin
I finally got a chance to inspect the diaphragm of an ESL63 and...
indeed there was a non-conductive coating on the side of the diaphragm opposite to the conductive coating.
Pics here:
http://www.diyaudio.com/forums/plan...oes-not-look-like-3-micron-3.html#post4126172
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