OK, I need some assistance from the collective again please, as I'm struggling to spec the capacitors. See annotated schematic below:
Firstly the power supply and output stage caps. The Mundorf Tubecap range is the closest range of non-electrolytic capacitors I've been able to find available which might fit the bill, so the first thing I want to check is whether my 'nearest match' should be okay, as some of the voltages are a little derated, but not less than the in-circuit values.
1) Pi-filter caps circled in red. Spec calls for 40uF, 630V. Closest TubeCap match: 47uF 600V. (500V DC in the circuit).
2) Pi-filter caps circled in orange. Spec calls for 5uF, 1000V. Closest TubeCap match: 10uF 1000V
3) Output stage caps circled in green. Spec calls for 80uF, one rated at 630V, the other unknown rating. Closest match: 100uF 550V (485V in-circuit).
(Ignore the one circled in blue as I've just found the Tubecap at that value is rated 750V, more than enough).
Secondly, there are some capacitors which have not been specified with a value, and I"ve searched through the DIY audio thread to no avail:
1) Shared cathode capacitor between the driver *SN7s paralleled with 500R resistor, circled in purple. The *SN7 datasheet specifies a cathode bypass cap value of 1.4uF but I'm not sure if that applies here? Any idea of what the ballpark value should be?
2) Two capacitors connecting the input stage B+ line to ground, looks like a bit of RCRC smoothing with 500 ohm resistors. I've circled those in brown. Any ideas on value / type? (looks like they should be at least 600V rated).
At least I know what to use for the coupling caps and I shuold be able to work out the resistor ratings with Ohms law.
Many, many thanks in advance.