WrineX
Of course, it won’t allow it, the blow of the beater on the drum membrane is produced by a lever blow of the muscular system of a healthy man, and the “blow” of the membrane of our speakers is produced by electrostatic force or electromagnetic force and the amplifier power applied to it. These are different physical processes
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I don't know if this will work with electrostats, but it works fine with cone speakers.
Phillips had the piezo driven MFB, but other manufacturers used the basic idea too.
The optical feed back was commercialy used by T&A if I remember right, to work with a woofer and /or subwoofer. As with all MFB products, they did not really promote the technical aspect, as potential consumers were thought to be sceptical of anything new. They just emphasized the extended bass reproduction.
Must have been around 1985.
A microphone based MFB was also aviable at that time, with a condenser capsule near the dust cap. Worked very well too, for low frequency.
Not to forget B&M who did full range MFB speaker, where the dome of mid and tweeter formed capacitors that gave position information. Much more refined than anything Phillips. (Sorry).
This "new" system is also from someone near to Piratelogic? Do you know if they plan to market it for DIY?
Phillips had the piezo driven MFB, but other manufacturers used the basic idea too.
The optical feed back was commercialy used by T&A if I remember right, to work with a woofer and /or subwoofer. As with all MFB products, they did not really promote the technical aspect, as potential consumers were thought to be sceptical of anything new. They just emphasized the extended bass reproduction.
Must have been around 1985.
A microphone based MFB was also aviable at that time, with a condenser capsule near the dust cap. Worked very well too, for low frequency.
Not to forget B&M who did full range MFB speaker, where the dome of mid and tweeter formed capacitors that gave position information. Much more refined than anything Phillips. (Sorry).
This "new" system is also from someone near to Piratelogic? Do you know if they plan to market it for DIY?
At your example was a dynamic cone and closed box. The spring was the closed air's volume. The static driver and its dipole configuration is totally different situation. However, your interpretation is false again, because the moving air mass isn't pure damper - see the enormous, undamped resonance at fullrange electrostatic panels.
Good idea! I think, 3-4 independent coil can scan the membrane movement profile. Perhaps you can make weighted summation of induced voltage, which represents the acoustical behaviour of driver.
Bakes&Müller used the metalized domes of mid and tweeter as parts of a variable capacitors. That way they could measure the very small movement and apply a correction signal. If this works for a dome tweeter, it should be possible with an electrostat. The undelaying problems are the same you have with the LED and LED receiver. The advantage I see is that you directly work with voltages. No need for optical or mechanical sensors. The polarizing voltages complicate things, but this should be manageable
B&M did this in analog technology. Today it should be a little less complicated to realize.
B&M did this in analog technology. Today it should be a little less complicated to realize.
It depends on what conditions the measurements are taken, you can measure room resonances instead of panel resonances.
And then, did I say that the air mass completely copes with the problem of the main resonance of the panel?
I wrote under what conditions the air mass effectively copes with damping and these conditions are here in earlier messages.
its a complicated thing , and as i said many times before, a planar magnetic might be the worse candidate to try it one, and dont even mention ESL planars.
but.. well, a person can play/dream its interesting what it could be used for and by the looks its not so much getting a lower distortion, but it could solve other problems just with shear power consumption. if its worth it... thats a whole different question
but.. well, a person can play/dream its interesting what it could be used for and by the looks its not so much getting a lower distortion, but it could solve other problems just with shear power consumption. if its worth it... thats a whole different question
WrineX
I recommend that you follow my path, make several pieces (2) panels and connect them together in a package, I guarantee that you will be delighted with the addition of bass .Then I will show you how you can dampen the main resonance, but first I will make several measurements to be 100 percent sure.
well i do know the technique of using multiple membranes with different resonances (i think i seen a video about it once, might have been yours ?)
Now maggies use something similar but with one foil (apogee uses another option not rectangular. or different tensions over the foil) and Martin Logan and a few others use multiple spacers and one foil.
Now stretching multiple foils is not something i like if i did i would have added coil if i can, still on the list , using single ended, not using steel then use 2 foils... by doing so you get some benefits of push pull (one foil moves towards the magnets one away) and you could use 2 resonances and no steel required, and you use all the field the magnets can put out.oh and you dont need twice the magnets... still need to build a bigger test to confirm, so i do look out for your findings ! its always interesting to see what people come up with !. i just dont want to strech allot of foils for one speaker i hate that job haha
Now maggies use something similar but with one foil
(apogee uses another option not rectangular. or different tensions over the foil) and Martin Logan and a few others use multiple spacers and one foil.Now stretching multiple foils is not something i like
if i did i would have added coil if i can, still on the list , using single ended, not using steel then use 2 foils... by doing so you get some benefits of push pull (one foil moves towards the magnets one away) and you could use 2 resonances and no steel required, and you use all the field the magnets can put out.oh and you dont need twice the magnets... still need to build a bigger test to confirm, so i do look out for your findings ! its always interesting to see what people come up with !. i just dont want to strech allot of foils for one speaker i hate that job haha
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It would be a pity if you don’t try to do this (combine two drivers into one package (one after the other), it’s not a matter of resonances at all, but of increasing the signal pressure, for bass this is extremely important in the case of large films, large films do not have enough pressure , and here you can get it, you just need to work a little. Come on, I’ll root for you🍻.
The doubled membrane at static drivers causes doubled max. driving force (6dB increasing of max. SPL), but the mechanical compliance of system will half. At planars is not necessary doubling the complete moving system: the voice coil quantity's increasing works alone too. However, the operation will be symmetrical "push pull" at planars with dual membrane, but with quasi "single ended" magnet structure.
Double membranes may reduce 2nd harmonic only.
Our ear is producing up to 10% second harmonic at lower frequencies.
Guess how many % 3rd harmonic distortion our ear is creating? 0.1 to 0.2 %
This means that putting effort in reducing 2nd harmonic is not a very good idea!
Its actually the opposite... 2nd harmonic in the speaker is masking the 3rd harmonic. So what I am saying is that if you have a push pull stage that eliminates 2nd harmonic you will instead hear 3rd harmonic and remember our ear is much more sensitive to 3rd harmonic.
Did a test with dipole woofers with double drivers. Both facing the same way and compared to facing opposite direction. Facing the same way is preferable! And it can be proven by psychoacoustic research. Let this sink in and then start to think about a figure "THD", that do not take into account if it is the 3rd 2nd or the 7th harmonic you are measuring. just add them all together and provide a short answer to audio nirvana... THD. Imagine that you can add several % 2nd harmonic to a music file a, no one can hear it. but if you add 0.1% of 5th and/or 7th harmonic you hear it directly. This is probably the reason why many people love their single ended amplifiers. Even though the THD is awful. Look at the FFT spectra! 2nd harmonic masks out higher order distortion.
Our ear is producing up to 10% second harmonic at lower frequencies.
Guess how many % 3rd harmonic distortion our ear is creating? 0.1 to 0.2 %
This means that putting effort in reducing 2nd harmonic is not a very good idea!
Its actually the opposite... 2nd harmonic in the speaker is masking the 3rd harmonic. So what I am saying is that if you have a push pull stage that eliminates 2nd harmonic you will instead hear 3rd harmonic and remember our ear is much more sensitive to 3rd harmonic.
Did a test with dipole woofers with double drivers. Both facing the same way and compared to facing opposite direction. Facing the same way is preferable! And it can be proven by psychoacoustic research. Let this sink in and then start to think about a figure "THD", that do not take into account if it is the 3rd 2nd or the 7th harmonic you are measuring. just add them all together and provide a short answer to audio nirvana... THD. Imagine that you can add several % 2nd harmonic to a music file a, no one can hear it. but if you add 0.1% of 5th and/or 7th harmonic you hear it directly. This is probably the reason why many people love their single ended amplifiers. Even though the THD is awful. Look at the FFT spectra! 2nd harmonic masks out higher order distortion.
And we don’t need to increase the stroke of the membranes, we need more attack of the membranes in order to quickly move a mass of air into space, that is, hit the drum with a mallet, but not gently stroke the drum as one membrane does.
Interesting - how much dB do you think the third membrane will add to the 6 dB already existing, it looks like it will be the technology of the gods?
Just in case, let me remind you that my sub has 6 membranes and 8 stators.
About will be newer +3dB SPL, because the force 1,5times. But the compliance decreases further, causes higher resonance frequency.
No matter how you make a dense coil on one membrane, it will not replace two coils on two membranes + a mass of air tied between them in a closed space.and thats what i am drawing up
This makes the moving system heavier, and this, in turn, is very necessary for low frequencies.
8 stators. ESL ? i mean its quite a different thing. im talking planar magnetic drivers