Re: New Pre-Amp Tubes
Most tube manufacturers mearly buy tubes from other companies, match them, and then brand them themselves. As a result, you can buy two sets of the same tube type from the same company, but there's no guarantee that they will be the same. Tubes are marked as to what factory they're made in, much in the same way an LP has a stamper mark that shows the mastering and pressing plants used.
For brand new tubes, I would use Svetlanas, but they are very expensive. How much are you looking to spend? If cost is an issue, you can go with Groove Tubes, which are generally of very high quality.
I prefer using NOS tubes for preamp stages. NOS stands for New Old Stock, and are original tubes from the golden era of tube manufacture but are unused. These are pretty pricey, tho. If you play rock/metal and are looking to go in this direction, I can recommend using Siemens tubes from Germany. You can find preamp Siemens circa 1970's. I find them to be the best high gain preamp tubes I have ever heard, and use them in my Marshall, Rivera, and Engl.
If you're on a tight budget, I would recommend Electro Harmonix. They're a bit wooly, but sound much better than Chinese tubes. Hope you find this helpful!