Tube Break in Period / Method

Just rolled out the Stock tube out of my Music Hall 25.3 DAC and replaced it with a NOS JAN Sylvania 6922. (Mullard was out of my price range) How long should I expect the break in period to be and what is the best method? Set a track on repeat or just leave the unit on?


Only you can be the judge of when the tube is settled in. I don't see any advantage in placing a lot of wear and tear on your equipment in an effort to speed up the process.

Also, the original tube was biased at the factory and a different brand of tube may or may not be operating optimally with the current bias setting. This is most likely not user adjustable. So, if you are not satisfied with the sound or if you feel the new tubes are not living up to your expectations you may want to go back with the original tubes.
40-50 hours with a signal running through it. Just play music and sit back and listen and enjoy...
You may notice a difference in the first 10 hrs. Then another in about 50. Hopefully they sound good right away and then just get better in that 50.

I don't think it's best to run it non-stop for the 50 hrs. I think it's better to cycle them. Run them for 4-6 hrs then let them completely cool before the next run.

Do have music playing thru them and vary the volume. Don't go real loud in the first hours.

Most important....enjoy.
Honestly just sit back relax and listen to music with your tube amp in your system. The tubes will get better with time. For me with a tube amp it was a couple of hours. Tube preamp or tube dac a day or so.

Before I came to the realization above this was how I was breaking in my tube dac and tube preamps. I have a 5 disc CD changer and I would put varying music and 1 Isotek break-in disc in there. I set it to play all 5 discs so my tube stuff would get a signal going through it for 4 to 5 hours straight. After the music stopped I powered down everything and restarted the process after everything cooled down. I did this periodically over 2 weekends as I was home. All in all I got 60 hours on the tubes. I'm not sure if this made an improvement as I couldn't recall what the tubes sounded like in my system before this break-in process.

If you want to follow my madness to the dark side feel free. Honestly I say now just sit back and listen. If it doesn't sound good after a couple of listening sessions then you may have to get a different tube.
Things are warming up nicely. I also called Tube Depot and they said they would swap them out for full credit if I was not satisfied. They stand by their stuff.