Hi Tobias, I'm aware that the clock at the switch has no importance from the timing perspective. Still, normal crystals are pretty noisy. The Ultra clock is one of the best in the world. It has phase noise levels above 130 dbv at 10hz. When you swap the crystal by this clock it's clear in seconds. You feel almost like a life attendant at a concert. At first when the clock is still cold, the phase noise levels are not that good, but after a few hours it's already much better and only after 48 hours it's fully stabilized.

In the first few hours it only gets better, until it decreases again after 6 hours. Slowly the DAC clock is pushed out of phase. This happens everytime when the stream becomes too clean.

I think when the signal is weakened by the filters and edges become less steep due to smoothing then everything is okay. I'm really positive now that it's not only about noise. A stream can get too stable as well and cause trouble to the DAC clock.

Yes, maybe it's that simple, but how to achieve that?

I think that the blockwave (stream) itself is already noise to a DAC

When the sound became dark (DAC crystal out of phase). I think it would make sense when I would give some examples.

Adding a new linear powersupply will solve the problem for 4 days (until some level of break in is reached) . I have tried this at least 8 times 🙂

Replacing a high grade powersupply by a less good powersupply. This prevents the crystals from synchronising, so the dark sound is solved, but it's not the same as with the better powersupply.

Replacing the ethernet cable will solve the problem for 2 hours. I have tried this more than 10 times.

Adding CAT8 makes things worse. Adding noise by adding for example a switching powersupply somewhere in the network makes things better.

Adding antennas to the ground system solves the dark sound, but on other levels is less good.

Disconnecting the audio system for 8 hours, solves dark sound for 4 hours.

Using less good power cables will solve the Dark sound (to some amount).

Using a new power cable no matter where in the system will solve the problem for 48 hours (probably a certain level of break in) I have tried this at least 20 times.

Adding powernetfilters like Kemp SNS or Furutech NCF clearline will cause dark sound

I think I can give more than 50 other examples that suits my explanation 🙂

The cleanest possible signal into the last passive filtering must be the goal, i am thinking.

A WiFi extender with clean power is one way that makes sense to me and apparently measure well, from a noise perspective. (I am not sure exactly how ERIC is measuring?)

If WiFi can´t be used then i am not sure since everything on the connected network might add different types of noise that needs to be cleaned up by the last passive filter.

Hoi Wijnand,

First of all, I am no expert in clocking but it seems after all the variables you changed , you never changed the clock. You seem to use a “super” clock integrated in the switch, if I am correct? Is the clock sharing power with the switch?

Also everyone in audiophileland swears by burned in cables and equipment, linear psu ea. but your results are better with new cables and smps. Without judgement, that is a quite remarkable observation. Imagine if you could have the common advantage of the former besides a stable DAC clock, best of both worlds…

A few indepently powered clocks are recognised as being top, besides the PF you are using. For example Mutec ref 10 and the top range Afterdark clocks, would that be worth exploring, if you not have tried so? Could they offer some “stabilty”  that the PF can not deliver?

I have been following the progress of a user on the other side of the planet with a PF 2.16 X ultra custom (3 Pink Faun OCXO Ultra clocks on processor, motherboard and USB PF card + externally powered by Paul Hynes DR7t+ ) server that maybe could help you sharing his point of view. I do not recall him at all mentioning a degrading effect over time. I wonder if I should connect the both of you?

Wijnand trust me I am only trying to advance what you are up to without knowing what you are up to ;-).

Food for tought.