Interesting quote from Steve.
I wonder....Are you for sure he is talking about "our amps?" Not having the context of your interaction, from the quote alone it sounds like he could be referring to the Taboo specifically, with a Torii Jr as a different reference point for how a 47 uF cap can effect rectifiers more intensely???
If looking at the quote as a general statement only, I got confused by the placement of his recommendation not to use "anything below 20uf." Since he started with the Taboo being forgiving due to a lower current draw, then moved into the Torii Jr's being less forgiving due to larger current draw, then he goes into the 20 uf minimum....In the quote context, this this could imply the 20 uF minimum as being for the Jr, and by extension, more of his amps??? Or if the context is about the Taboo, this recommendation could be specifically for your Taboo??? This made me think context probably matters, hoping to represent and understand what Steve is saying accurately.
Relative to whether we can generalize these things, I did not look at all amps on the Decware site, but I thought I recalled the 53YGT as recommended in the Torii IV spec area, and it is. But for the Torii Jr, only 5U4s are listed in its spec area. I wonder if this introduces another variable. I am not am engineer, but I was under the impression that the chokes on the Torii IV help absorb inrush current. If this is true, I wonder if the Jr does not have a choke, and that this
might be a reason why lower rated rectifiers are not listed???
None-the-less, the Torii IV is a higher power Decware amp, and the 5Y3GT is listed for it.
As to ratings, Steve's saying 20 uf cap rating for 5Y3GT got my attention, being sure I had double checked my memory of 32 uF max for a 5Y3GT before posting that figure above.
Because it is easy for me, I often use the Valve Museum site for first reference, and go further if needed. Here is the page I got for a 5Y3GT
http://www.r-type.org/exhib/aai0014.htm picturing a Sylvania, and saying 32 uF max.
So I looked further, and found
a pdf from r-type.org (guessing Valve Museum also based on the site link above), a pdf appearing to be from GE, and rating the tube for a 20 uF Filter cap. As with many pdf spec sheets from companies, it does not specifically say max, just the filter cap rating.
Then looking at frank.pocnet.net where he puts up PDF spec sheets that appear to be from the companies, I got:
GE - 32 uF (where the valve museum pdf from GE says 20!)
Brimar - max 32 uF (this one says max)
RCA - 10 uF
RCA #2 - 20 uF
Tungsol - 20 uF
And finally, from tubebooks.org, I found a PDF from RCA with a filter capacitor input rating of 20 uF.
I had not run across these kinds of discrepancies before, and it was a good learning experience, but where does it leave us in the question of 5Y3GTs and filter caps in Decware amps?
Then looking at type 80s, many PDF spec sheets had no "capacitor input filter" value or "operating cap value" listed, but I found these:
Radio Museum general page for type 80 - 32 uF max
Valve Museum general page type 80 - 32 uF max
Valve Museum general type VT-80 - 32 max
Are you as confused as I?
Presumably the the "capacitor input filter" ratings could be "max" ....or not???
My mind is addled. ;)