Sounds like you only have one thing to turn on/off - and that is the tube preamp. You can always turn on your phono preamp with the tube preamp set to something else, which effectively mutes any "pop" the phono preamp would create. So it sounds like there is no question to answer here. If you can't turn the amps off momentarily to avoid the "pop", you have to just turn on the linestage preamp when you are ready to listen and suffer the pop.
My preamp (Hovland HP-100) must have some sort of internal muting circuit that turns off once the preamp is powered up, because I always turn my amps on first and never hear a pop. However, I pose the following questions:
How bad (i.e. loud, sudden, forceful) does a pop need to be before it risks damaging the downstream equipment? Can an amplifier be damaged by a "pop" (we hear pops when playing records...). Is the loudness of the "pop" associated with powering up a tube preamp at all dependent on the setting of the volume control? If a pop occurs in an empty room with nobody there to hear it, does it really make any sound? (whoops, I'm getting too zen here)...
My preamp (Hovland HP-100) must have some sort of internal muting circuit that turns off once the preamp is powered up, because I always turn my amps on first and never hear a pop. However, I pose the following questions:
How bad (i.e. loud, sudden, forceful) does a pop need to be before it risks damaging the downstream equipment? Can an amplifier be damaged by a "pop" (we hear pops when playing records...). Is the loudness of the "pop" associated with powering up a tube preamp at all dependent on the setting of the volume control? If a pop occurs in an empty room with nobody there to hear it, does it really make any sound? (whoops, I'm getting too zen here)...