Hey! Me again. I (sort of) got one panel assembled, but not framed. As soon as I plugged in the bias supply, the diaphragm made a squeaky stretchy sizzle sound. No program sound from the panel during a quick test. Then when I unplugged the bias supply, it sounded like the whole thing was "relaxing", or untensioning for about 4 minutes or so.
I am guessing this means I didn't get the Mylar stretched correctly.
How long after unplugging the supply before it is safe to work on? (detach wires and so forth.)
I am guessing this means I didn't get the Mylar stretched correctly.
How long after unplugging the supply before it is safe to work on? (detach wires and so forth.)
The mylar has no sufficient tension and sticks to the stator when you apply bias voltage. Too high mechanical tension is also not recommended as it will a) cause resonance frequency to drop over time and b) there is a possibility of partial resonances entering the game, worsening impulse response.
You can know how much the film is tensioned by placing some dots with a thin permanent marker and measuring before and after stretching.
My recommendation is not to exceed about 1.5% or so in elongation but there are many other factors including the type of mylar.
You can know how much the film is tensioned by placing some dots with a thin permanent marker and measuring before and after stretching.
My recommendation is not to exceed about 1.5% or so in elongation but there are many other factors including the type of mylar.
You can short the three wires from the panel together and this will dissipate most of the charge.
A lot of times after doing this there may still a small charge present it isn't any thing to be worried about but is enough to startle you should it discharge through you! He,he,he,he
The squealing you heard is most likely one of the panels having some HV leakage some where in the stator coating and it is arcing to the diaphragm.
If the Diaphragm was sucked into one of the stators then two things could have possibly caused this,
1# A low tension as already mentioned,
2# An imbalance caused be the leakage of one of the or both of the stators.
You will hear some crackling and noise as it powers up as it gets charged up, and once the voltages get equalized it should set there with absolutely no noises coming from the panel.
On my last panel I delt with fixing such spots many many times over until I could finally get to a 10Kv of bias with no noises as I raised the Bias voltage from 0V with just a little crackling as the HV tension got higher but that was it after everything was in balance.
If you get any pops, clicks, chirps or squeals coming from the panel then you most likely have some leakage issues to solve.
These types of sounds can also be caused from leakages within a faulty step up transformer as well.
But, I doubt that this is the case at only 4Kv of bias and new transformers
I have had this happen when I was using some old 6V6 OPT's that finally gave out on my first set up.
If you tried to do a test and got no sound make sure that if you are using two transformers to feed the panel that they are in-phase with each other.
If they are not you will not get any sound what so ever!!
I have done this a few time as well !!
If you are using the Antec's there is no guaranty that there polarities are the same.
I have already contacted them about this and it seems that they have made no notes on there data like they said they were going to do.
When I called them they didn't even know what the term polarity meant!!!
From a transformer company.......Go figure !!!!
jer
A lot of times after doing this there may still a small charge present it isn't any thing to be worried about but is enough to startle you should it discharge through you! He,he,he,he
The squealing you heard is most likely one of the panels having some HV leakage some where in the stator coating and it is arcing to the diaphragm.
If the Diaphragm was sucked into one of the stators then two things could have possibly caused this,
1# A low tension as already mentioned,
2# An imbalance caused be the leakage of one of the or both of the stators.
You will hear some crackling and noise as it powers up as it gets charged up, and once the voltages get equalized it should set there with absolutely no noises coming from the panel.
On my last panel I delt with fixing such spots many many times over until I could finally get to a 10Kv of bias with no noises as I raised the Bias voltage from 0V with just a little crackling as the HV tension got higher but that was it after everything was in balance.
If you get any pops, clicks, chirps or squeals coming from the panel then you most likely have some leakage issues to solve.
These types of sounds can also be caused from leakages within a faulty step up transformer as well.
But, I doubt that this is the case at only 4Kv of bias and new transformers
I have had this happen when I was using some old 6V6 OPT's that finally gave out on my first set up.
If you tried to do a test and got no sound make sure that if you are using two transformers to feed the panel that they are in-phase with each other.
If they are not you will not get any sound what so ever!!
I have done this a few time as well !!
If you are using the Antec's there is no guaranty that there polarities are the same.
I have already contacted them about this and it seems that they have made no notes on there data like they said they were going to do.
When I called them they didn't even know what the term polarity meant!!!
From a transformer company.......Go figure !!!!
jer
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You can grind the edges off with a hand grinder.
It will take some time but it is the best way I know of.
Check out some of these threads on working with perforated sheet metal,
http://www.diyaudio.com/forums/planars-exotics/166280-jazzmans-new-stat-panels.html#post2174937
http://www.diyaudio.com/forums/planars-exotics/166280-jazzmans-new-stat-panels.html#post2820194
http://www.diyaudio.com/forums/planars-exotics/165495-start-finish-esl-hybrid.html#post2160966
http://www.diyaudio.com/forums/planars-exotics/158115-material-esl-4.html#post2093878
http://www.diyaudio.com/forums/planars-exotics/165495-start-finish-esl-hybrid.html#post2160952
http://www.diyaudio.com/forums/planars-exotics/162127-different-ideas-esl-panels-3.html#post2126078
Taping the edges help but you still have to get rid of the sharp points otherwise it will just punch right through the tape.
This is because the high voltage charges concentrate at the smallest and sharpest points.
This was the only flaw I had in using window screen.
The sharp points of the wire were hard to insulate even when they were buried deep in some silicone rubber.
It was because of this my little panels finally burned as I repaired them over and over and over!!!!
I could have just made a new one for the time I spent repairing it.
This is where working with the sheet metal has its benefits.
jer
It will take some time but it is the best way I know of.
Check out some of these threads on working with perforated sheet metal,
http://www.diyaudio.com/forums/planars-exotics/166280-jazzmans-new-stat-panels.html#post2174937
http://www.diyaudio.com/forums/planars-exotics/166280-jazzmans-new-stat-panels.html#post2820194
http://www.diyaudio.com/forums/planars-exotics/165495-start-finish-esl-hybrid.html#post2160966
http://www.diyaudio.com/forums/planars-exotics/158115-material-esl-4.html#post2093878
http://www.diyaudio.com/forums/planars-exotics/165495-start-finish-esl-hybrid.html#post2160952
http://www.diyaudio.com/forums/planars-exotics/162127-different-ideas-esl-panels-3.html#post2126078
Taping the edges help but you still have to get rid of the sharp points otherwise it will just punch right through the tape.
This is because the high voltage charges concentrate at the smallest and sharpest points.
This was the only flaw I had in using window screen.
The sharp points of the wire were hard to insulate even when they were buried deep in some silicone rubber.
It was because of this my little panels finally burned as I repaired them over and over and over!!!!
I could have just made a new one for the time I spent repairing it.
This is where working with the sheet metal has its benefits.
jer
Last edited:
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