12AU7 tubes for a Rouge Audio Sphinx V3 Integrated

@mesch if you can, try to take listening notes first 20hrs, 100hrs, 200hrs. Often times people don’t give it enough time with the stock tubes -or- internal caps before replacing them prematurely. Me included on a few occasions. Good lessons learned.

While I’m over here making cool upgrades on mine, friends chose to "leave it alone" keeping the stock tubes and caps in their units for 200-300hrs. Their new vs. well burned in amps and stock tubes, caps, sounded better, given some patience and extra time.

Then say at 200hrs if/when you still decide to swap in other vintage tubes, you’ll know what changes the changed tubes actually make. For your consideration.

@decooney  That is exactly what I intend to do. I may have 30 hours on the unit now. Running a computer as a server into it as I work on the new house. Will get to the 200 hour point within the next month. After that time I will consider all the suggestions acquired herein and purchase a pair of NOS tubes for trial. 

It's all fun & games with no one getting hurt :-)

@paul_lindemann  Thanks for the recommendation. 

@thecarpathian Please let me know if you put your tube up for sale. Thanks.

Brimar 12au7 in Sphinx v3