Super Reverb '65 RI - Changing Output Transformer to Match Speaker Load

[bob p]

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FWIW the Ultimate Attenuator, basically a load resistor driving an SS back end, uses a single 30 ohm power resistor for any amp , no change for 4, 8 or 16 ohm ones.
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The actual circuit is VERY simple, the raw speaker signal directly drives (through a wire wound pot) a couple TO247 devices...

It sounds like what you're describing is an attenuation/reamplification device, where the SS output ends up driving the speaker load.
I would imagine that S/N suffers under that paradigm.

[loudthud]

It's important to remember that the 6L6GC wasn't available in the early 50's. Check the early schematics and 6L6 {nothing}, 6L6G, 6L6GB or 5881s were specified. Those tubes only had 19W plate dissipation rating. Not the 30W of the 6L6GC.

[pdf64]

I think the simple explanation is that Leo was after low distortion.

[ATTACH=CONFIG]40299[/ATTACH]

bob, I think that chart is for SE operation; note that the HT is rather low also.

I think that the 4k2 p-p OT came in with the 5881, eg 5F6A.

For the 6L6 based p-p amps, operating conditions didn't change much after that until the late 70s, so I suspect that Fender didn't intend the 6L6GC models to have a wider conduction angle than the 5881 models; so adjusting the bias for 70% dissipation at idle for 6L6GC may result in a wider conduction angle, higher idle dissipation, shorter tube life and generally more stressed conditions than Fender may have intended.

[Chuck H]

It sounds like what you're describing is an attenuation/reamplification device, where the SS output ends up driving the speaker load.
I would imagine that S/N suffers under that paradigm.

Not significant in my experience. I expected that too, but not so. Maybe because your tone is already hissing like a snake if you're troubling with an attenuator