more volume = less bass??

[Chuck H]

Simply driving the amp to OT saturation and achieving power compression narrows the power-bandwidth, making the highs and lows seem less apparent. This is NOT a bad thing

No, not at all. It's an important part of the specific tone of certain classics. I just prefere not to include this highly variable and subjective approach in my designs. I think most of the time that it turns out to be a good thing, it's more of a happy accident. There have certainly been plenty of amps built with under sized OT's that have a bad rep for both tone and reliability. I don't have enough experience with the nature of transformer design to get predictable results this way. Also, there are other ways to control hi and low without using the OT as a post power tube EQ. As noted, this could even be a reliability issue. That is, unless you know transformers well enough to spec a design with an underrated stack that will saturate without having the rest of the OT in danger. It seems to me though that this practice would make for a less efficient OT. And I prefere my designs be efficient. It seems to add touch sensitivity.

, and like Steve said, is actually a GOOD thing.

Actually, he said he prefers NOT to design with intentionally under rated OT's. But he did recognize a phenomenon that could make it useful.

I have actually designed and built amps with ganged volume pots that decrease bass response as you approach "10".

I've done this too. It's very effective. But it contradicts pointing out that the OT can be used to roll off bass as the wave becomes square and saturation occurs. I do it because I DON'T design with small OT's.

If it were a high-fidelity amp, you'd have lots of iron in the OT to minimize the chances of saturation and a multiple-stage PI/driver to deliver clean drive to the power tubes. It's a different animal, whereas reduction of power-bandwidth is a no-no. In overdriven guitar amps, you actually want and need this.

True, true. I have built amps with over sized OT's as in Steve's example above. Sometimes the results were less than satisfying. But if you don't go overboard the amp can come to life and sound like it can breathe. It's just a matter of personal design experiences and goals of course.

Chuck

[yunger]

if you want to soften things up a bit couldn't you just drop the value of filter caps or B+ to find a good balance of fullness and mush?

[Old Tele man]

...the human ear does not "hear" different frequencies equally nor linearly, but rather responds to highes faster than to lows.

... Look up Fletcher-Munson curves.