Originally Posted by alphaman
Unclear as to why putative lower-quality ceramics are being exchanged for original/stock (which are decent-quality poly/film, albeit low-cost Chinese variety and not Panasonic or WIMA). Or did you o'scope stock vs. NP0 and noted improvements? Also, did you change (tweak) cap values to match replacement OPA, as originals were ideal for OPA2604?
I counted the Filter of Low Frequencies for more best sound.
NP0 ceramics now this best decision for a filtration ΣΔ DAC.
Read for example a cycle of articles from Cyril Bateman (http://ru.scribd.com/doc/2610442/capacitor-sound). Here some quotes:
Note however it is crucial to use only close tolerance and low distortion capacitors for both these positions. Preferred types
being 1% Foil/Polystyrene or COG disc ceramic.
Obviously a good C0G ceramic capacitor would work almost as well as my first choice of Polystyrene, provided the COG capacitor is available selected to 1% tolerance.
C0G From my tests it has almost no measurable harmonic distortion. COG ceramic is more stable with time and temperature than mica capacitors and from my tests COG can produce less distortion.
For 100 nF capacitance we find the lowest distortions are generated by choosing either C0G multilayer ceramic, metallised film PPS or PP.
For example COG ceramic is probably the most stable, and most nearly perfect of all commonly used dielectrics. COG disc and
multilayer ceramic capacitors do not rely on pressure contacts or metal spray connections onto their electrodes. One maker’s
products should measure consistently and with remarkably low distortion. Those from a different maker may measure slightly
Many articles have been written about capacitor behaviour, mostly by authors having little knowledge of capacitor design and construction. As a result, many popular but false capacitor myths have emerged:
a) All ceramic capacitors distort.
b) Dielectric absorption causes smearing and compresses dynamic range.
c) Polypropylene is an inefficient material.
d) Capacitors are highly inductive at audio frequencies.
e) ESR of a capacitor has a fixed value.
differently, but again should be consistent from batch to batch..
alphaman I think to you still it is necessary to be gathered knowledge before writing posts with such contents. Read more technical literature, instead of foreign subjective opinions.
Edited by burnwaygta4 - 8/13/13 at 1:30am