tube pre amp and Krell FPB 600

CT0517, I do have the owner's manual, I have read exactly what you have specified many times, it is a whole page, I do not believe it would hurt nothing to do the power up and power down scheme that Salectric has told me, I never thought of it, makes sence to me,I'm going to do it, The tube/solid state digital source I use straight to my amp in no way could spike anything following Salectric's advice, I have always used all solid state, likly that may be the reason I never thought of doing a procedure for on power and off power of Tubes mixed with sold state audio equipment.

^^Even if you have solid state you can get a thump. The reason you don't is your preamp has an automatic mute.

Many tube preamps do nowadays too.

I always get a thump sound over the speakers when I turn my amp off, it's really alot of power, seems normal to me.

I've had 3 Krell amps over 10+ years and always drove them with tube preamps (SF, McIntosh, CJ ...) and never had a problem.

There are reasons for rules. If not followed, probability of problems increases.

I leave my SS amps on continuously per the manufacturer's instructions and get a thump through the speakers when I turn my tube pre-amp off. This is normal according to the manufacturer. There is some woofer excursion but not as great as it is when playing at very loud volumes, so I don't worry about it.