I've been going a little nuts as I'm sure quite a few on here could appreciate swapping caps in the signal path of my preamp. I've had great differences with LCR Polystyrene, Amtrans PP, CDM Mica, and the ceramics which were in there. PP can be very detailed but bright, styrene smoothner but maybe not the most accurate and veiled somewhat. Interested in some of your favorites - 100pF is my value.
100pF in the signal path? Like in series? That's a suitable value for an RF coupling cap, not audio...
Perhaps its a shunt load cap?
Or are you looking at a compensation cap (needed for stability)?
What's the preamp circuit, and where is this cap within it? Otherwise its only vague speculation that can be offered...
Perhaps its a shunt load cap?
Or are you looking at a compensation cap (needed for stability)?
What's the preamp circuit, and where is this cap within it? Otherwise its only vague speculation that can be offered...
Some people claim to detect dielectric used by ear, in exact same value caps.
Until I see proof of that {using double blind testing) I remain skeptical.
Correct that to very skeptical.
Define "better sounding"
Beyond 120% subjective description, expectation bias, "listening with your eyes", etc.
In any case, something which sounds different will measure different, that's for sure.
The opposite does not necessarily happen.
As in:
* A Piezo tweeter sounds shrill and nasty.
Measurement shows an 8-10dB peak at 3 kHz.
Good.
Measurement matches that gross problem observation.
while
P
* Amplifier 1 measures 0.1% distortion; Amplifier 2 measures 0.01 % distortion.
Difference is easy to measure.
Easy to detect by ear?
Not that easy ... to put it mildly.
Yet a group of people claims they can.
Oh well.
Beyond 120% subjective description, expectation bias, "listening with your eyes", etc.
In any case, something which sounds different will measure different, that's for sure.
The opposite does not necessarily happen.
As in:
* A Piezo tweeter sounds shrill and nasty.
Measurement shows an 8-10dB peak at 3 kHz.
Good.
Measurement matches that gross problem observation.
while
P
* Amplifier 1 measures 0.1% distortion; Amplifier 2 measures 0.01 % distortion.
Difference is easy to measure.
Easy to detect by ear?
Not that easy ... to put it mildly.
Yet a group of people claims they can.
Oh well.
Once again: any capacitor is not a simple capacitor. It is mix of a capacitor with series inductance and resistance of tails and plates, and shunt leak resistance of dielectric and packaging, that configures a complete filter. So it is obvious that changing the kind of capacitor maintaining the absolute value, will change amplifier's frequency and phase behavior.
But as JMF said, I'm too extremely skeptic you can listen such a difference.
But as JMF said, I'm too extremely skeptic you can listen such a difference.
My choice would be Wima FKP2 film/foil and if i want silver mica then i would buy Charcroft.
No experience with NOS boxed silver mica's.
Soviet K71-7 stacked polystyrene could also be a choice.
S+M orange polystyrenes, stacked, are said to be the best but the the range of values possible to find is extremly limited, usually 3,3n ( or 33n, i forgot ).
No experience with NOS boxed silver mica's.
Soviet K71-7 stacked polystyrene could also be a choice.
S+M orange polystyrenes, stacked, are said to be the best but the the range of values possible to find is extremly limited, usually 3,3n ( or 33n, i forgot ).
The pioneers got it right originally and this comprehensive testing concurred regardless of rating.
The OP hasn't got back with the answers to post #2, but I'll guess this 100pF is for compensation/stability as mentioned in #2. I'll further suppose the circuit works fine with 102pF, but is prone to oscillate (at some high ultrasonic frequency, of course, resulting in increase in noise and a definite change in sound) with 99pF. Thus capacitors with "different dielectrics" will sound different depending on their exact capacitance value, not their dielectric.
Components don’t have “sound”. Circuits do.
Two different circuits, assembled from different components, can have exactly the same sound or transfer function. Remember the famous Carver challenge?
https://www.stereophile.com/content/carver-challenge
Two different circuits, assembled from different components, can have exactly the same sound or transfer function. Remember the famous Carver challenge?
https://www.stereophile.com/content/carver-challenge
Are you claiming some capacitors in audio have a self-resonant frequency down at 100kHz or lower? Because that's what you need to start affecting phase and frequency response in the audio spectrum.
Well, maybe he likes throwing a few multi farad supercapacitors in there because... more is better?
https://techweb.rohm.com/know-how/nowisee/7549/
There is a more specific and better explanation than mine.
There is a more specific and better explanation than mine.