There is truth there, regarding film caps at infra-red frequencies, where polar plastics like polyester and polycarbonate films strongly absorb energy at very short, characteristic wavelengths. The effect is also exploited in chemical analysis by IR spectroscopy techniques.
Whether there are echoes of the effect at low frequencies is not so clear but Douglas Self had been seriously working on measuring and verifying results with various cap types commonly used in audio circuits, ever since examining Cyril Bateman's articles on the subject and his test gear, quite some years ago. The links to Bateman's work below, are to the second part and a follow-up article, available from Jan Didden's site and bookzines.
https://linearaudio.nl/sites/linearaudio.net/files/Bateman EW 08 2003 distortion v time v bias.pdf
Linear Audio | your tech audio resource
I would also like to add this link to the thread:
https://www.dadaelectronics.eu/uploads/downloads/13_Theoretical-and-practical-Electronics-papers/Capacitor-Sound-C-Bateman.pdf
https://www.dadaelectronics.eu/uploads/downloads/13_Theoretical-and-practical-Electronics-papers/Capacitor-Sound-C-Bateman.pdf
Hi Piotr,
the link does not work anymore, could you post a new one please?
My friend has just got REW FFT working on a PC. Would that be usable for measuring distortion in capacitors, anyone ?
More explicit recommendations for different applications would be much appreciated - PSU, small values, large values and Speaker caps.
the link does not work anymore, could you post a new one please?
My friend has just got REW FFT working on a PC. Would that be usable for measuring distortion in capacitors, anyone ?
More explicit recommendations for different applications would be much appreciated - PSU, small values, large values and Speaker caps.