Output Cap Voltage Question

[greg788]

For the 2.2uF for DC blocking output cap position, what sonic difference does a higher voltage rating in a capacitor provide? In other words, is there any advantage sonically to using higher voltage rated caps over a lower voltage one of the same brand and model / part number, where all else is equal except voltage rating?

[Doc B.]

Higher voltage rated caps use a thicker dielectric than lower voltage rated ones. In theory the dielectric is primarily what gives a capacitor its "color". By extension, the higher the voltage rating the more coloration of the tone. In theory.

[Paul Joppa]

Some observers say a higher voltage rating sounds better. In my opinion, the difference is somewhere between tiny and imaginary ...  :^)  If there is a difference, it probably depends on the specific construction and materials of the cap.


My two cents.

[greg788]

So I literally just ran my own experiment because I hate all this theory and supposition in high end audio (cables, caps, blah blah). I just remembered that I have 2 pairs of CDE 940C caps, one pair 2uF and 600V, the other pair 2.2uF and like 850V. I felt the higher voltage pair was more coherent and relaxed sounding. By coherent I mean it kept instruments separated better, that sort of thing. And seemed higher in resolution.

Of course it's impossible to consider this a true DOE as the differences I heard may be due to differences in household voltages, more distortion on the AC grid between the two tests (as the day goes on, you've probably noticed sound quality goes down -- and I don't subscribe to AC line filtration, another joyous "theory" I've tested ad nauseum to no discernable difference on many occasions).

[Doc B.]

Don't forget how much time each cap has had a high potential across it as a factor too. You may have to run them both for several hours/days/weeks before you can make a definitive choice.