From what you are saying, by swapping in another preamp, the phono input overload and the preamp itself are fine. And the overload zapped the input stage of your Adcom(?) monoblocs?
Hooked up Shiit Mani incorrectly
I feel really stupid right now. I hooked up my Shiit Mani to my phono input on my Adcom GFA 555 preamp causing both my speakers to start distorting. Once I realized my mistake I shut the system down. I believe I may have damaged both my amps in the process. Both amps are humming when turned on. What damage could of done? Any guidance would be greatly appreciated