DAC break-in question

how about the manufacturers "break them in" before selling. 

some manufacturers, like Zu, do break-in before shipping, but most do not have the time, space, money to do so...

@katzenjammer27 

l have just purchased a new Denafrips DAC and was informed they ‘run-in’ it in for 100 hours prior to delivery. I think this is also a very good quality control move to ensure everything meets specifications and avoid any QA issues.  With DACs in particular I’ve read they should not be switched off but left in standby, presumably to keep capacitors fully loaded for when the unit is switched on.  My current Bel Canto 3.7 DAC is permanently on as per the manufacturer’s advice. Paul from PS Audio recently discussed run in apropos speakers and Upscale Audio also supports the view of great differences among non to run in speakers. As for running HiFi  in general and hearing sound changes there is evidence that electronic components change with use (both improve and with time deteriorate) but with human sound memory being so poor it’s hard to know if improvements are real. Which is what @jasonbourne71 was pointing out in his inimitable fashion, I suspect the only way to do this would be to buy two identical new items that supposedly improve with run-in and rub one in and then compare and measure new versus run in? Maybe a challenge one of Audiogon’s many HiFi dealers could easily arrange. To be honest I’m not on the fence with this as I hear differences between HiFi components, not always for the better. To get back to the topic running in the new DAC is good practice and shouldn’t need it to be connected to a preamp or amplifier stage to run in.

@audphile1 

The analog stage is on but there will be no signal on the analog outs from the DAC if the amp the DAC is connected to is off.

Surely the analog out will carry the output signal, presented as a voltage?  This will be a line-level signal of a few volts maximum.  The impedance of the line-level inputs to the amplifier will be high - around 10-k Ohm up to 1-M Ohm of more.  So hardly any current will flow in the interconnect whether the amplifier is switched on or not.  The impedance of the interconnect will allow a tiny AC current to ebb and flow in the interconnect even if it is open-circuit at the amplifier end.

I'm in camp amp needs to be on to pass full signal through output section of dac.

As for burn in, I absolutely hear it, this over many decades and all sorts of equipment. But in any case, it all becomes a non issue once components have a certain amount of hours on them. Problem arises when one doesn't believe in burn in and dismisses/banishes newly purchased equipment, I've had personal experience in buying equipment from churners who didn't believe in burn in, I don't let on a thing, they assume equipment lousy, may be willing to let it go at a lower price.

I don't even bother dealing with burn in much anymore, have a desktop or bedroom system I can use for burn in purposes. Speaker, speaker mods and amp output tubes are the only instance in which I have to put up with burn in.