Inspired by member henkel
http://www.diyaudio.com/forums/showthread.php?s=&threadid=64538
I want to ask those who know something about caps for signal coupling.
Do any of you have experience with silver mica in any applications where they perform better than film caps in the signal path?
I have heard that silver mica are the best for signal coupling, better than all the rest (all types of film or foil or paper in oil).
The problem is that they do not come in larger values than 0,1uF (100nF) and they are very expensive, and large!
So they are only a possibility in active filters and RIAA where you only need small capacitor values.
http://www.diyaudio.com/forums/showthread.php?s=&threadid=64538
I want to ask those who know something about caps for signal coupling.
Do any of you have experience with silver mica in any applications where they perform better than film caps in the signal path?
I have heard that silver mica are the best for signal coupling, better than all the rest (all types of film or foil or paper in oil).
The problem is that they do not come in larger values than 0,1uF (100nF) and they are very expensive, and large!
So they are only a possibility in active filters and RIAA where you only need small capacitor values.
Hello!
Try contacting Gintaras at www.kwtubes.com or at his eBay shop "kwtubes".
He used to have some huges silver micas to reasonable prices. A friendly and honest guy too...
Cheers
tom
Try contacting Gintaras at www.kwtubes.com or at his eBay shop "kwtubes".
He used to have some huges silver micas to reasonable prices. A friendly and honest guy too...
Cheers
tom
Check this post rearding silver mica sound: http://www.diyaudio.com/forums/showthread.php?postid=262664#post262664
Peter Daniel said:
Peter, as I read the thread it is about silver mica in RIAA equalising.
Here they are in the feedback loop and not in the direct signal path as in an active crossover like the one attached. Will this do a difference, or what do you belive?
The signal wil pass directly through caps CH.
Attachments
Konnichiwa,
Yes, in my own applications I find Silver/Mica capacitors superior to anything else.
However, my applications usually have several 100V across the capacitor, which is VITALLY important.
Any plastic material will be subject to a number of issues from being an electrostatic speaker to being a capacitor microphone. These issues become more crucial as the voltages go up but coupled levels stay the same.
The essential monolithic construction of silver/mica types simply does not allow any of this to happen. Also, Mica, unlike any other dielectric has certain interesting "secondary" properties, which contribute (cannot really say more here).
So there are applications where silver mica capacitors rule, but they usually involve significant DC Voltage gradients across the capacitor. Without DC you may find Polystyrene and/or teflon better.
Sayonara
klitgt said:
Yes, in my own applications I find Silver/Mica capacitors superior to anything else.
However, my applications usually have several 100V across the capacitor, which is VITALLY important.
Any plastic material will be subject to a number of issues from being an electrostatic speaker to being a capacitor microphone. These issues become more crucial as the voltages go up but coupled levels stay the same.
The essential monolithic construction of silver/mica types simply does not allow any of this to happen. Also, Mica, unlike any other dielectric has certain interesting "secondary" properties, which contribute (cannot really say more here).
So there are applications where silver mica capacitors rule, but they usually involve significant DC Voltage gradients across the capacitor. Without DC you may find Polystyrene and/or teflon better.
Sayonara
I think that ANY cap works better with lots of DC across it. Think about how several volts AC, with very little DC, on a cap in a typical amp FB network is going to sound. Or RIAA network. Less AC, but about the same amount of DC.
But as for SM caps..............
Nelson likes them. Paul McGowan likes them. Phred hates them. His thoughts are similar to J. Carr's. They are stable parts, but perhaps without the right DC:AC ratio, they may not sound right on your application.
Jocko
But as for SM caps..............
Nelson likes them. Paul McGowan likes them. Phred hates them. His thoughts are similar to J. Carr's. They are stable parts, but perhaps without the right DC:AC ratio, they may not sound right on your application.
Jocko
Konnichiwa,
Yes and no.
I agree, I always like several time the AC levels worth of DC across capacitors, but fairly loosely rolled plastic cap's (eg. most "audiophile" types and electrolytics) tend to become rather effective capacitor microphones as the voltage goes up.
The only ones immune are stacked ceramic using a non piezoelectric ceramic, stacked film types (shame Siemens/Epcos x'ed the polycarbonat ones!) and stacked silver mica (rolled silver mica are as bad as rolled film, in experience) or Micamold.
So, where voltages are low and signal levels high rolled film may very well do better than silver mica.
Sayonara
Jocko Homo said:
Yes and no.
I agree, I always like several time the AC levels worth of DC across capacitors, but fairly loosely rolled plastic cap's (eg. most "audiophile" types and electrolytics) tend to become rather effective capacitor microphones as the voltage goes up.
The only ones immune are stacked ceramic using a non piezoelectric ceramic, stacked film types (shame Siemens/Epcos x'ed the polycarbonat ones!) and stacked silver mica (rolled silver mica are as bad as rolled film, in experience) or Micamold.
So, where voltages are low and signal levels high rolled film may very well do better than silver mica.
Sayonara
Silver mica capacitors will soon be availale in sizes up to 6.8uF (!), see:
http://www.thel-audioworld.de/bauteile/glimmX/glimmx.htm
The stuff of many peoples dreams. But the prices bring you back to earth.
I have used silver micas in feedback locations in an RIAA filter with two active op amp stages. They were better than polyester, but teflons were much better than silver mica. I could not say that I heard particles in the air, just the sound was unnatural. Other applications lead me to conclude with Kuei: they are better in applications with larger DC voltages.
http://www.thel-audioworld.de/bauteile/glimmX/glimmx.htm
The stuff of many peoples dreams. But the prices bring you back to earth.
I have used silver micas in feedback locations in an RIAA filter with two active op amp stages. They were better than polyester, but teflons were much better than silver mica. I could not say that I heard particles in the air, just the sound was unnatural. Other applications lead me to conclude with Kuei: they are better in applications with larger DC voltages.
Kuei Yang Wang
"However, my applications usually have several 100V across the capacitor, which is VITALLY important."
Jocko Homo
"I think that ANY cap works better with lots of DC across it."
In a series looking very deeply at capacitors, published in Electronics World, Cyril Bateman has demonstrated that DC across any type of capacitor always increases distorsion.
Cyril calls your thoughts above myths. They are unfunded technical speculations and speaking of "VITALLY " is intellectually dangerous.
~~~~~~ Forr
§§§
"However, my applications usually have several 100V across the capacitor, which is VITALLY important."
Jocko Homo
"I think that ANY cap works better with lots of DC across it."
In a series looking very deeply at capacitors, published in Electronics World, Cyril Bateman has demonstrated that DC across any type of capacitor always increases distorsion.
Cyril calls your thoughts above myths. They are unfunded technical speculations and speaking of "VITALLY " is intellectually dangerous.
~~~~~~ Forr
§§§
I wrote : "DC across any type of capacitor always increases distorsion."
Read "High DC".
Capacitors distort when there is AC voltage accross them, which means that's when they have a significative impedance at the considered frequency. So it is essentilly in filters and power supplies that they have influence on the sound reproduction.
~~~~~~~ Forr
§§§
Read "High DC".
Capacitors distort when there is AC voltage accross them, which means that's when they have a significative impedance at the considered frequency. So it is essentilly in filters and power supplies that they have influence on the sound reproduction.
~~~~~~~ Forr
§§§
slawney said:
THel sells EMZ styroflex caps, the square orange dudes.
These are remakes of 1% Siemens KS B31531 styro's.
Used to get the original Siemens in Germany for twice that price, for RIAA applications, and that was wholesale price.
The only good deal you can make at THel's, for anything other it is Th-Hell
Silver Mica capacitors in crossovers
In my 50 years of designing speakers and passive crossovers I have found that silver mica capacitors have excellent properties and provide conducive results in high frequency filtering. This is especially true for HF drivers (tweeter/supertweeter) where in my experience they work remarkably well on there own or in conjunction with film capacitors.
In my 50 years of designing speakers and passive crossovers I have found that silver mica capacitors have excellent properties and provide conducive results in high frequency filtering. This is especially true for HF drivers (tweeter/supertweeter) where in my experience they work remarkably well on there own or in conjunction with film capacitors.
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