Why 600v when the pre only puts out about 2v. Don't smaller voltages sound better?2 Vac signal...
What is the DC power supply voltage applied to the plate of the output tubes? The caps block the DC voltage from the power amp's inputs.
The more voltage tolerance, the better. Too close and the cap will overheat and may blow. Heat is the enemy of the cap and you need a little padding. 800v is better than 600, etc. The REL and Jantzen along with the Mundhorf offer good voltage tolerance and great sonics. My fave is the v-caps. Not for those looking to spend 20.00 for 4 caps, but worth every penny. jallen