100 watt Marshall Power Transformer B+ winding really ~180mA?

[capehead]

I think it should be considered that the PTs for these classic amps were designed in an era when tube rectifiers were the norm and B+ winding were probably expected to included sufficient series resistance to accommodate them without the need for external resistors.
So B+ windings had to be saggy, have poor regulation, and get hot during sustained heavy loading.
Even 100 watt (well, nominal) / 4 tube amps might use tube rectifiers, eg http://bmamps.com/Schematics/Selmer/selmer_pa100.pdf
Just because the Marshall PTs didn't have rectifier tube heater windings, I don't think we should assume that transformer designers would immediately develop / implement a whole new set of 'ready reckoners'. Rather I suspect they would still use the old design templates developed for tube rectified PTs, in regard of winding AWG, window size etc.
So for the classic response, a saggy B+ may be pretty much essential, whether or not tube rectifiers are involved.
And the lower than expected B+ current ratings may just be reflecting that somehow?

This is perhaps as logical explanation (if this under powered B+ thing is true) as to why and how the 100 watt Marshall ended up being built around this value. As I mentioned in a previous post, the first 100 watts (as well as the rest of their products) were being built with off-the-shelf parts and I'm pretty sure the power transformers which Marshall used in these amps were about the biggest one could obtain from Radio Spares; and these ones had their HT winding rated at 200mA despite how physically large they were (I'm guessing the reason for this was the extra windings/taps).

[capehead]

I was being silly with that... but I'm probably one of the 0.083% of guitarists who likes their distortion to come from a cranked up amp, be it 1W or 180W...
I've never had the pleasure of playing a non-MV Marshall, but I did get to try a 76 JMP 100W... it was awesome! I'm just sorry my only cab is 100W & a 2x15" so no cranking on 10...

Justin

I hear you man, in certain contexts a preamp based distortion is really the only way to go; most of the amps I've ever built have been based on this concept which is why I'm hoping to have an amp which does the complete opposite (plus as I'm getting older, the uber-gain/metal sound doesn't do much for me anymore). Many years back as a wide-eyed teenager, I was able to experience an old NMV Marshall on top of 2 vintage 4x12's with permission to 'crank it' and when I say I experience, I meant that quite literally; oh and it was a white 1976 Gibson flying V I was playing through it! This was before musical instruments/equipment became investment pieces

[Justin Thomas]

I hear you man, in certain contexts a preamp based distortion is really the only way Togo...

No, no, I avoid those contexts! I "tolerate" using distortion pedals... to be honest, I probably play more like if Neil Young had taken up the synthesizer...

Justin

[capehead]

No, no, I avoid those contexts! I "tolerate" using distortion pedals... to be honest, I probably play more like if Neil Young had taken up the synthesizer...

Justin

I thought he did for that one album? https://en.wikipedia.org/wiki/Trans_...ng_-_Trans.jpg