Please help a new tube user!

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...

Sorry to have neglected your second question. Buy a multimeter, as you can do so much more than a voltmeter with it. A good one(and you don't need anything great) can be had reasonably(less than $100). Biasing a Jolida is simple. Not the easiest(like the CJ red LEDs), but really easy. There are connections on the topside of the amp for your meter. Simply make the connection(you measure and bias one tube at a time) for each of the four 6550s(replace them with JJ KT88 during your eventual retube), and measure. If it is out of range, adjust it into range. Child's play. In fact, I have a piece of literature from Jolida where they wanted to convey how easy it is. They took a bunch of women who work there(not sure why they needed to stress that), and set them up with an amp, a meter, and the Jolida instructions. None had a problem biasing an amp(so they say). You can also experiment with the bias; definitely changes the sound. Don't go light years away from the specs, but you may like the tube biased a hot or cold.