Tobes, I haven't seen these instructions. I've always just followed the lighting of the diodes on the face of the power supplies as my guide. But, from experience, if the power supplies are not fully stabilized, you can get some wonky sounds. For my system, I'm generally doing a 10-15 minute warm-up in any event for everything to stabilize (tube phono, tube monoblock amps, air bearing TT).
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