Power Cycling Mystery

I and several people I know have noticed that every high end DAC we've ever owned benefits from a quick power recycle. I have no idea why but I suspect it has something to do with resetting clocks and flushing data (no need for knowledgable people to flame here....I'm just theorizing) I'd love to know why but the effects are clear enough to my ears that I now do it as a matter of course before most listening sessions.

vhiner, I think you're onto something here...I notice this to. My dCS is software based...so I am sure, like a laptop...it's a computer and resetting cleans something out.

There was a earlier thread on dCS clocks that recycling seems to do something...

It could be a simple relay that is making a bad connection. When you cycle it off, it will clean itself and make a new connection, at turn on.

Another possibility is, somewhere in the circuit, there can be a bad connection. The inrush current (at turn on) can cause a little arc, and temporarily weld/solder the contact back together. This also can happen inside a semiconductor itself.

Hi Bryon,

I don't see anything implausible about that, and probably the explanation is along the lines of the things the others have suggested. The circuit reset that occurs at power on undoubtedly clears out and affects a great many things, which may in turn affect subtle interactions between seemingly unrelated circuits, caused by effects such as noise coupling.

It's probably not possible to hypothesize anything more specific without knowing the details of the particular design, and perhaps even if those details are known.

The one additional point I would make is that I recall that some time ago you found that removing some unneeded modules and the top cover from the G68 resolved a heat problem it had. Are you still running with the top cover removed? If so, perhaps that is contributing to rfi that may be radiated from the digital circuits in the G68 into other components in the system, which could conceivably result in the haze and high frequency distortion you described via intermodulation with signal. The rfi conceivably being sensitive to circuit conditions that would be affected by a periodic reset.

In any event, you've discovered a simple tweak that is beneficial in your particular system, so I'd just go with it!

Best,
-- Al

Thanks everyone.

Vhiner - That's an interesting theory about the clock. If power cycling results in better clock performance, then it might also result in less jitter. That's consistent with the type of improvement I experience from power cycling -- less high frequency harmonic distortion and imaging haze, both of which I associate with jitter.

Hi Al - That's an interesting theory about RFI. I never thought of that. I will put the top back on and see what happens. Thanks!

bc