New Sensor will have a 80uF/450VDC capacitor, as
well as a selection (albeit small) of Mallory Twist-Lock
can capacitors. That should get you going, but I have
performed and would suggest you do a power supply
modification. The first question to ask yourself is how
much 'sag' do you want?
A) If you want 'some' get the 20X20X20X20uF
@475VDC can and parallel the first two sections. 
B) Wire everything up as normal.
C) You ask... 'What about the 4th filter?"
D) You take my advice and add a seperate radial
capacitor (16uF/475VDC) from New Sensor and put it
in a spot that you can run THAT capacitors' ground
TO THE INPUT JACK ALONG WITH THE
GROUNDS FROM THE 1ST STAGE. Trust me, the
hum will 'magically' disappear. No one but old time
tube jockeys will know why, and you can look smarter
than most others. This is a common problem with any
amplifier that used FP cans; the 'last' capacitor is
closest to the outside of the can and subject to picking
up hum. You'll most likely hear it when the amplifier is
on '10'.

 

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