I just found this device on Amazon, it has 8 outlets and can be interconnected for more outlets. It is cheap enough, only $125. I am not expecting much in the filtering section, as they don't even spec the number of surge joules it can handle or the bandwidth of the filters. But, what I do like about this is the fact it sequences the outlets on, which I do need. I recently blew a midrange driver when I accidentally flipped the control electronics power switch off before the power amps. That was a $3000 repair, with freight and insurance. Then, it morphed to $6000 when I discovered the manufacturer upgraded the speakers and the original drivers were no longer available, so both heavy speakers had to be shipped cross country. Granted, it was a pretty significant sound improvement, so I didn't feel so bad when I got them back. I ordered two of these units for 16 controlled outlets, I will check them out, and report back here on how well it works.
https://smile.amazon.com/Outlet-Power-Sequencer-Conditioner-Controller/dp/B07P76C2PF/ref=sr_1_6?crid...