Leaving DAC on all the time OK?


I have a Museteax IDAT that I leave on all the time. The power button is on the back of it and the DAC sits in my cabinet so it is difficult to turn it off. When the transport is off the dac is trying to lock onto a signal. Since their isn't any signal the blue led light on the dac blinks. Am I wearing out the dac prematurely? How long before the unit needs to be serviced? Thanks in advance. Phil Brady.
philbrady
I usually agree with Nsgarch but tubes should be left on too. They live much longer since they are not expanding and compressing each time you turn the unit on and off.

Raquel, I am usually very envoronmental conscience but I never know when I'll get to listen and I found that I don't like waiting the various warm-up times. But I do agree that we should all be as "green" as possible.

p.s. It's nice to see a woman beside Elizabeth on the Gon. Welcome from all of us.
I have an Electrocompaniet DAC that I leave on most of the time.
Funny thing is, occasionally when I sit down to listen, it has this funny "out of phase" sound to it. Almost as though the entire system has been turned inside out. I would liken the sound to a kind of transistor radio feel. It really strange. It's not like the phase has bee switched 180, that would still be listenable. But it's like nothing else I've ever heard.

All I do is re-boot the DAC and all is fine. That's about the only time mine gets switched off.
Imin2u -- I know we're not talking about power tubes (in DAC's) but I thought generally tubes were like cars -- "It's not the years, it's the mileage" So that every hour powered up is an hour of useful life gone. Not so you say?
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Tubes last longer if turned off when not in use. The cathode has a limited lifetime where it is capable of full emission. There may be some turn-on stress, but that is outweighed by burning the life out of a tube.

On turn on, the filament is cold and conducts current with little resistance. The high in-rush current causes very rapid heating and thermal stress. Also, if the unit utilizes solid state rectification, the power applied to the plate come on almost immediately while the cathode may take some time warming up. This could lead to a condition called cathode stripping.

These issues are mostly non-existent if the unit uses tube rectification (the rugged rectifier takes all the abuse and slowly turns on the rest of the unit. In units with solid state rectification, the turn on can be rapid, but a lot of experts think that the "damage" is relatively minor.

It is possible to put a thermistor or other device in the power supply to slowly bring up the power in tube gear if that is a concern.
In response to your initial question I would agree with Jond, leave the DAC and the transport on.

However, since the topic has gone a bit further into the value of warm-up from cold start vs a constant on condition I've made an observation with a SS CDP left on 24/7.

When the rest of the system has been operating well past any reasonable warm up point (all tubes) when I use this CDP (Wadia) initially the upper frequencies are definitely overbearing in the highs. Dissapears within about 30 minutes or less (replayed the disc to verify). Thereafter, in that session there is no problem whatsoever.

Anyone else observed this in a different, or same, devices?