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Can voltage be mixed with coupling caps?

I’m updating coupling capacitors in the line and phono sections of my preamp. Because of cramped space, I need to divide each 1.0 MFD 400 VDC position into three caps of .33 MFD. But two will be at 600VDC (on top of the board), and one at 400 VDC (mounted under the board). Is there any compromise of performance in mixing the voltages of these high end Teflon caps in each summed coupling position?

Also, …how lead sensitive are coupling capacitors in a preamp. Again, because of larger caps and limited space, I need to make the leads asymmetrical (one will be twice as long as the other). The original mounting hole’s spread is much longer than I will need for the new caps, but the caps are fat and need to be moved away from the heat of the tubes. Generally speaking, do leads contribute to capacitor performance? Any tweaky opinions on this?
pandro

Showing 1 response by georgehifi

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georgehifi
10,312 posts
 
Pandro, Atmasphere is right, never ever mix coupling caps, and they will smear the sound as the sound travels through them at different speeds, and they will especially smear at each ones time constant points if they are different values or voltages. Always use a single HQ cap coupling.

Saying that the best cap is no cap at all if the circuit allows, and the DC offset can be nulled out.

However it is OK to mix and parallel up de-coupling, or power supply caps, and it is encouraged, as it lowers the total power supply ESR (series resistance), which "stiffens" the supply and gives a tighter controled sound to the bass.

Cheers George
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