Surge protectors without noise rejection


Is there such thing as a duplex outlet or power strip surge protector, that won't alter sound because of built in noise filtering with surge? Seems there is filtering with surge only protectors. Even Brickwall seems to have some sort of filtering...is this inherent with surge devices?
dejule
I use a Brickwall in front of a BPT Pure Power Center (PPC). I've compared with the Brickwall in place with the BPT PPC , and without (BPT PPC direct to wall outlet).

The Brickwall filtering does no real degradation. Note that I use a Brickwall with the 20 amp surge unit.

I've also compared the Brickwall to some "filtering" power conditioners. Again, the Brickwall had no to minimal sonic effects, whereas the power conditioner had more sonic effects (particularly on dynamics).

IMHO, the filtering used in a Brickwall is pretty inert.

You can change how a Brickwall "sounds" by changing the AC plug or outlets. I snipped off the standard nickel plated AC plug and replaced it with a nice solid copper plug. That gave me more of the sonics I was seeking.
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Thanks everyone, are Zero Surge the same as Brickwall, the enclosures look the same...
Hi Bob, Surge X says that the SA1810 does have filtering...is this audiable? The site also says they ues chokes and inductors...wouldn't that compromize the sound?

Mooglie, Good to know about brickwall...that you don't hear any change in sound. Wounder if they also use inductors..?