I posted this earlier, but as a novice poster, I think it was in the wrong place.
My question is: does one need both a dedicated surge protector and a dedicated AC filter? I'm using Chang Lightspeeds for filters. They are relatively expensive and provide little energy clamping (35-45 joules). On the other hand, surge protectors providing up to 3000 joules energy clamping can be had for relatively modest cash outlays. If one needs both, does a proximal (nearer the AC wall outlet) surge protector degrade the performance of a distal line filter?
Thanks, John
PS: If this has been answered already, tell me where to look.

These are some very good questions, and this is probably the best place around here to ask them. The information available at Chang Lightspeed would suggest that their line filters are also intended to provide surge protection (at least as far as this mechanical engineer can tell - the EE's in the audience may be able to give better opinions). I'd suggest giving Chang Lightspeed a call.

A good surge protector should be able to protect equipment without overly restricting current, but for power amps you really do have to keep an eye on that. Folks around here have had good luck with TrippLite, Panamax, and Brick Wall for surge protection, if you feel that you need some supplemental protection.

There is not enough information on the lightspeed site to say for certain but the fact that it uses a "clamping device" tells me its probably just an Metal Oxide Varistor (MOV), the same as in any other surge protector. So in most cases if what you want to add is just surge protection (no additional filtering), then put the lightspeed after that, you should have no problems. But any device will destroy themselves if hit with a big enough surge.
What I do find interesting is the use of the power factor correction. This explains why they get the "instantaneous" current they state. My experiance with PFC in high power situations (medical lasers) is that they added noise. So my assumption is that they filter after that.

The other part that is, well, skeptical IMHO, is their statment regarding coils and transformers. While what they state technically is correct regarding the time lag, what you have to remember that in most cases, the units you are powering have transformers in them. In some cases toroidal (like Outlaw amps). Then the AC gets convertered to DC and stored on capacitors. My point is that these devices are already in the path of the ac current, adding another isolation transformer (if properly sized) should not induce any lag that would be noticeble in the output. Also remember there is a transformer on the pole to your house to begin with.
I have used isolation transformers up to 10KVA with and without PFC's for high power lasers and other systems including audio, and have not had any issues with current lag causing a problem with the output.
While I don't doubt the lightspeeds work, and their engineering sound (just another way to do it) and are great products, its just the reasons they state why "others" are bad is dubious.
BTW I am an EE. From what I have read, Gonk has better EE knowledge than he lets on.

Thanks for the information. Now I'm not sure I need the filters, but since I have them I will add proximal surge protection.
Regards, John