preamp vs power amp distortion/drive

[starbuck26]

ONLY if you turn it up loud enough.
Power tube distortion mainly occurs when the tubes are close to producing up around their rated output.
Any distortion you hear before that point is only coming from the pedal.
To make the power tubes distort in that Blues Jr. you have to have them putting out the whole 15 watts and that's pretty loud.
Without using something like that Weber Mass, you have to have an amp up about as loud as it goes to get the power tubes into their distorted range.

You're right. My bad. It occurs to me that I was thinking about it in the wrong way.

If you put an overdrive/distortion pedal straight into the effects loop, you're going to hear what the pedal/guitar sounds like without preamp saturation.

My hot rod deville sounds somehow more 'boxy' to me when I bypass the preamps... but I really can't qualify the sound.