john curl said:
No problem.
<http://www.amccaps.com/products/hts/AMC_High-Temp-Stacked_2005-11.pdf>
NP0 to 2.2 uF 50V
X7r to 47 uF 50V
(or smaller at 200 V)
Gerhard
I just received some samples of .1 uF multilayer NPO ceramic caps. They are not cheap (I think $4 ea. in small quantities). I have not measured them or tried them but I think they are important.
The remaining stock of polystyrene film is getting used up and not recommended for new design. I have talked to most of the US vendors and they all say the same. And they all know who has how much of what film. Polypropylene is the next choice in practice but its less stable in value and has a higher tempco. Teflon is fine but too expensive for anything less than ultra expensive. And long lead- hard to get stuff. Also the large size of the film caps in larger values will increase the inductance and self resonance frequency.
I suspect we will all need to learn more about ceramic options. Mica are also good, can be close tolerance and values to 5000pF but expensive. The reconstituted mica from custom caps is fine stuff however very expensive and special purpose (high voltage precision timing circuits) and still very large.
The remaining stock of polystyrene film is getting used up and not recommended for new design. I have talked to most of the US vendors and they all say the same. And they all know who has how much of what film. Polypropylene is the next choice in practice but its less stable in value and has a higher tempco. Teflon is fine but too expensive for anything less than ultra expensive. And long lead- hard to get stuff. Also the large size of the film caps in larger values will increase the inductance and self resonance frequency.
I suspect we will all need to learn more about ceramic options. Mica are also good, can be close tolerance and values to 5000pF but expensive. The reconstituted mica from custom caps is fine stuff however very expensive and special purpose (high voltage precision timing circuits) and still very large.
gerhard said:
I called them and most of the other vendors of MLCC's and they never called back. Very annoying. Its like they don't want business.
Maybe I'll try their local rep and see if I can get a response.
stinius said:
No, you aren't. What puzzles me the most is clearly audible music in difference track in "green pen" sample.
I listened to all of those tracks through some cheap PC speakers because my PC is too far from audio equipment, but the difference tracks are rally interesting - the amount of "information" mostly correlates with "audio-beliefs".
john curl said:
Mouser and Digi-Key both sell through-hole NP0 capacitors in sizes up to 0.1 uF. For example 80-C350C104J1G5HA and 445-2613-ND.
If you like the Mundorf ZN, you ought to try the silver/gold/oil and the Duelund ones.
http://www.duelundaudio.com/index.asp
Sigurd
http://www.duelundaudio.com/index.asp
Sigurd
PMA said:
Thanks for the input Demain. It would be interesting to do a DA test on one of your ceramics. I suspect that it won't be as good as polypropylene or polystyrene, but who knows?
stinius said:
In the discussion with Bear the issue was whether it would be easier or not to detect cap effects in a track vs a sousa band. What I suggested was to listen to the difference, NOT the separate tracks.
What is of course most revealing is listening to the *difference* between the two tracks in each set. If you listen to the difference between a clean track, and one that has gone through a cap, you hear basically noise, even when you crank up the gain and listen with earphones.
Now if you listen to the *difference* between the clean track and the sousa track, you hear a sousa band playing. No need for extra gain or headphones, you just get music.
Now think again. Go back to where you embed that difference back in the original track. Get that noise back into the no-cap track. Get that clearly recogniseable sousa band back into the clean track. Now, which one would you expect to be easier to detect?
That was the issue.
BTW, if you load the track sets initially, the difference track may not yet be there. You have to click 'extract difference'. The program then goes through some numer crunching and shows the alignment between the two tracks and the level matching it does. In my case, these numbers were 0.00023dB and a fraction of a uSec.
It is also instructive to listen to the difference between a 256kB MP3 and the original .wav file. Also in this case you can actually follow the music!
Edit: Bear, for the difference tracks, no need to listen through a hi-end system. Just use whatever you have, even the laptop build-in speakers. Remember, we're listening to the *difference*, not (yet) the track itself.
Jan Didden
LCR Components is even making ROHS compliant polystyrene caps. Farnell for ex sells them.
Sigurd
Sigurd
1audio said:
Rel is still making GREAT polystyrene caps. Film is now made in China. Still, it is OK, I am told, by one who knows these things (not anyone here).
In many aspects high voltage NPO ceramic caps are better and in certain applications polystyrene caps are even useless.
PMA said:
Maybe. I'll let you enjoy evaluating high importance parameters of no-caps-in-the-signal-path-polystirene-teflon-NP0-bla-bla-bla designs through a soundcard board full of cheap electrolytics.
Err... Ahem... Has anybody taken the time to listen to the difference between a clean sound track and one that has gone through a cap, as discussed for DiffMaker?
I thought all those here that insist on evaluating equipment through listening would jump at the chance.....
Jan Didden
I thought all those here that insist on evaluating equipment through listening would jump at the chance.....
Jan Didden
As much as my urge to shoot myself in the foot.
janneman said:
And? What's your opinion?
As I can tell there is difference information buried some 30dB deeper for poly cap sample then for ceramic. Regarding the relation between diff. information and audible differences I would say that audible degradation is proportional to level of diff. info (obviously) and fidelity of diff. info to original sample - eg. 128kMP3 is easily audible even on PC speakers and has the worst and loudest diff. track "music".
vuki said:
Yes, about 30dB delta is what I also found. But there is not a clear differential with the Z5U cap wrt the poly cap signal-wise. If you up the gain of the difference with the Z5U you hear the original music, somewhat distorted but still easily recognizeable. With the poly cap difference you need to increase the gain much further, but you hear essentially a similar residue.
What puzzles me that the effect of either cap is not some kind of bad distortion, but essential the original sound at lower level. Like some attenuation effect. If you listen to the difference for the 128k MP3 for example, that difference sounds heavily distorted like a voice out of Startrek, and I can understand that because the MP3 coding just throws out parts of the spectrum. By comparison, both cap differences sound pretty civil. Strange.
The sousa track difference is much bigger of course, just listening to the difference without any additional gain it is already clearly audible. Since many claim that they can pick out the (more subtle) cap effects, they should score 100% easily on picking out the sousa tracks. But nobody wants to risk his/hers carefully nurtured reputation of GE, of course.... 😉
Jan Didden
What I find really interesting with those diff. tracks is how they wonderfully relate to those "audiophile prejudices"; if one listens to the amplifier diff. tracks one can hear that first two supposedly high quality amps have diff music at much lower level than HT amp. And sound characteristic of that music is "cold" for D-class amp, and soft for AB class amp, and awfully "dirty" for HT amp.
BTW I can easily hear sousa band if boosted in level for 9dB and hardly when boosted 6dB. This is via cheap PC headphones. I cannot hear it at 3dB boost even at high level - it's burried under noise of original recording, I suppose. I presume that it could be more audible trough decent audio system.
BTW I can easily hear sousa band if boosted in level for 9dB and hardly when boosted 6dB. This is via cheap PC headphones. I cannot hear it at 3dB boost even at high level - it's burried under noise of original recording, I suppose. I presume that it could be more audible trough decent audio system.
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