Surge protector

@squared80 -

For safety and reliability reasons whole house surge suppression units have a clamping voltage around 400V from neutral.  I can tell you from personal experience they don't do great with sensitive electronics. Lets talk specs though:

A 120V circuit goes up and down 60Vrms from the neutral, which has a peak of ~ 85V .

60Vrms = 60V * square_root(2) = 84Vpk

According to actual third party testing here with a 5kV surge the Furman PST-8 let an additional 40 Volts through. Lets do the math:

400Vpk - (84Vpk + 40) = 270V additional volts before clamping starts.

I quote the review here:

It turned a 5,000-volt surge into just 40 volts, thanks in part to a shutdown circuit that turns off all power when it detects a surge. The Furman PST-8 actually let less voltage through in our tests than high-end series-mode surge eliminators that can cost hundreds more.

@ozzy I've had similar experiences with a whole house unit.   The one piece of gear I lost was a laptop (Macbook Air with amazing battery life, so sad) which was the only piece of kit in my home that was not further protected by plug in strips.

@jea48 -

Class D amps may have a linear or a switch-mode supply in front of them. If linear, it’s just like any other amp and inrush current depends on whether the designer put an turn-on limiter on it or not. Larger amps really should have this feature.

If it’s an SMP supply though there’s almost always a smooth, low current ramp on until it stabilizes and turns on the amp portion.

PS - you can tell the difference by weight.  A linear supply is going to have a large transformer associated with it.

Dammit, I did the Vrms to Vpk conversion wrong..... my bad!

A 120Vrms has a Vpk of ~170V. 

Doh! It's been too long.