Basic surge protection with some noise filtering without strangling the amplifier?

@kirkwallace HA!  Oh he is SUPER interesting all right!  He owns the house, his first when he was younger, but he and his wife live in a different house a few blocks away.  He basically tore out the entire back 1/2 of the property and converted it into a giant shop (he use to work in steel girder construction in the 60s and 70s, helped build a few of our bridges).  So, when he retired, he rides his bike over here and works in the shop all day, and goes home!! 

That CODA is a beauty of an amp, and yes does have proper voltage regulation and supply if I remember right.  But I can see now why you would like to get some insurance on surges and some additional 'line filtering': I am certain someone is inducting something on the power lines in your building!  Maybe not an arc welder and a plasma cutter....but still...

@kirkwallace 

"FWIW, the Rowland 625 S2 is a class AB amp."

Yeah, my bad, I made that assumption based on the switch mode power supply. I still doubt that any line filtering would be advantages though, other than surge protection. The following link describes your amp.

https://www.jeffrowlandgroup.com/model-625-s2/

@amtprod 

"Isn't "voltage regulation" one of the three pretty critical components to proper system protection and filtering/performance?
I only mention because the OP mentioned "....without strangling my amp"
Wouldn't stabilized voltage delivery be critical?
I have a neighbor who welds quite a bit, and my lights will dim a little when he's doing a fair bit of plasma cutting and welding."

The amp's power supply handles all that.

What ever device you choose make sure it is stated as a non- current limiting design. 

I agree, @triton20trx. Certainly the Furman and AQ 707 discussed above make that claim.  i guess what i am asking is whether one should trust the manufacturer when they claim that?