OT saturation

[wall_of_sleep]

Can OT saturation produce results similar to browning out?

One of my builds leads to me believing this. Knocking this amp down on a variac or feeding it a lot of signal would sound near identical. Having upgraded to a larger OT the amp is now very clean. There was one issue that, when feeding the amp a lot of signal previously, the amp would stay distorted/pinched off for around six seconds or so.

[pfflam]

I am no amp specialist but, if I deciphered your question correctly, which in itself demanded concentration and effort, I think you may be experience oscillations from hot electrical currents being too close together, perhaps the lugs of a power tube and a wire or resister lead that goes to another component are too close or nearly touching.

I had this problem with my Marshall rebuild: the dress was pulled so tight in one spot it caused parts to come close to touching and the amp to oscillate from loud to quiet to loud. All I had to do was move the parts and address the dressing.

Of course I could be completely wrong and most likely am.

[pdf64]

There was one issue that, when feeding the amp a lot of signal previously, the amp would stay distorted/pinched off for around six seconds or so.

OT saturation is primarily a low frequency thing, though a better specc'ed OT will sound better (or a least different) throughout the frequency range.
What you're describing there fits the bill for blocking distortion.
http://www.aikenamps.com/BlockingDistortion.html
The OT will have almost no affect on this.
So you may not be driving the amp in quite the same way, so as to induce blocking distortion.

[EFK]

I had a National 1215 from around 1955-57 I believe which was a 2X6L6 amp that I 'modded' (not really - I just dropped the big honking resistor between the first two filter nodes from 10K to 3K) for a little more power. The stock OT however was pitifully small - I mean, like Princeton size - seriously. When the amp was cranked up and being hit hard, it did exactly what you described: complete brown sound, all mids, very phasey and washed quality to the sound almost fading in and out - almost like heavy power tube grid conduction, but it wasn't. I did temporarily patch in a bandmaster size OT and the "issue" (not really an issue as it could be used for a really cool swamp-blues effect) went away completely. So, I assumed it was complete OT saturation. I hear lots of talk about OT saturation being a good thing, but IF that was what was going on, it's not something I personally would want on a regular basis. MUD.

[teemuk]

Wait until you plug in a scope and see what the OT saturation actually does to the signal. You're in for a shock.