The ZLC by it's nature does have spike protection, yes, but not surge suppression. Our tube gear doesn't need surge suppression or voltage regulation, and most solid state gear has that incorporated into their own power supply.
In the ZLC the noise filtration happens before the Toroidal transformer inside the IEC connector in a metal shielded case to keep the transmitted noise that was filtered away from of the inside of the ZLC metal case and away from the TOROIDAL transformer and internal wiring. Here is what that looks like:

From there we go into the TOROIDAL transformer and after being magnetically decoupled the secondaries are shorted across a beeswax cap which further lowers the noise floor.
A transformer this size stores a lot of energy, so it's ability to deliver a sudden release of energy to your amplifier is superior to the wall outlet. To get an idea the kind of energy, the TOROID ways about 22 lbs. Drop that on your foot and that's pretty close to the stored energy potential : )
With a good aftermarket power cord and a ZLC you will absolutely have blacker backgrounds and way better dynamics. That was actually the reason for choosing a noiseless TOROIDAL that can handle 10 AMPs of RMS current. This is far more than any Decware system even with 6 components. But, even at 10 AMPS draw, there is a tremendous energy release available when compared to the smaller isolation transformers, that get noisy if you draw more than 2/3rds the rated power and go over 4 amps.
There are a many "power conditioners" out there to choose from. I know that if what you make doesn't actually make an obvious improvement, then people will be disappointed. To make an obvious improvement I believe that in the DECWARE world where everything is tubes and doesn't give a shit if the voltage is +/- 10 Volts, regulation is less important than isolation, and grounding is probably as important as isolation. Having everything from source to amplifier plugged into the same device creates a single-point-ground equal to each component and that alone would improve the sound of a lot of systems. And if that didn't do it just having higher quality hospital grade receptacles with high tension contacts and heavier metals throughout tied together with high quality stranded copper wire, copper jackets on the receptacles and close spacing to set the proper stage for a good power cord feeding a good amplifier.
In the past I would use always at least two of the small ISO500 Tripplite units because anything larger would have unbearable mechanical hum, so never was it possible get everything into a single ground point. Now that I can plug large amps together with source components and even my commercial power hungry tape machines all at the same time without not only hearing loud mechanical hum, but instead of experiencing sag, the stored energy gives everything a nice kick. And of course the captive power cord on the Tripplite models, while not a deal breaker doesn't do you any real favors either. As always, it's just a product designed to solve my own problems which I realize everyone else probably has as well.
I am anxious to see what Lon and everyone else who tries one here thinks of it! Call it confidence.
Steve
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