Please help a new tube user!

I would retube the unit. Try thetubestore.com fast friendly quick service large selection lots of tube info. I am also new to tubes and use cj equipment. I have had a couple of defective tubes; one burned out and the other was very noisey. So when to replacement was easy. I do not know anything about Jolida equipment you may want to write or call them. If they are anything like cj they will be more than happy to answer your questions.

You could test the tubes, but I would also be inclined to re-tube if only for the peace-of-mind effect. Definitely talk to the manufacturer to get their take on what works best with their products based on actual experience. Be very careful to find matched tubes with the correct combined values for each channel. Doing the NOS thing can be iffy and expensive -- there are some really good new tubes available today. Good luck.

Forget about changing the tubes until you evaluate the amp as it is. The first thing to do is to look at the tubes. See if there is a name on the glass. After that, set your system up, and LISTEN. Nothing wrong? Why change? I do recommend that if these are the original Chinese tubes in the amp, you replace them(at some point) with JJ(Tesla/Teslovak) KT88. The Chinese tubes seem to slow down the music, and muffle everything. To my ears, the Russian tubes do not have as nice a tone as the Czechoslovakian made tubes. But, so long as the tubes you get are OK(even if they ARE Chinese), they will do no harm. You can use the smaller tubes from Sovtek, JJ, Ei(best?), or the like. Next up is moving to a better power cord...