Went to buy Vandersteen 2C speakers and came home with a conrad-johnson Premier 11A.
I found a great deal on a pair of Vandersteen 2C speakers with Sound Anchor stands. I didn’t need them, but they are identical to a pair that I had back in the 90s. While I was there, the seller mentioned that he had an amp that he wanted to sell. It was on a shelf in a basement collecting dust. The price was right, so I bought it. He said there are about 40 hours on the tubes. Hopefully, the caps are ok. I’m thinking I’ll try a Wiim Ultra streamer with volume control just to see if everything works. I have old preamps by NAD and Rotel, but they aren't good ones.
Is there anything special that I should do before firing up the old girl? This is my first tube amplifier.
If I were you (which I am not) I would have a competent tech go through the amp. The amp is SS rectified making is easy to use a variac, but I would not use either of the variacs listed in this thread as they both would seem to be inaccurate crap - based upon reviews. The power tubes should also be checked and biassed.
DeKay |
@dekay I'm concerned about the variac as well. I won't use it without feedback from c-j. I downloaded the owner's manual. Adjusting the bias is pretty simple with this amp. I looked at the tubes again. The 5751 are GE. No brand shown on the 6CG7. Just some dots and U. S. A. |
You are welcome. Re the tubes. The 5751 is a lower gain version of the common 12ax7 tube. Some of the best 5751 and 6FQ7 tubes were in fact made in the USA so assuming those tubes test well and are functional, I’d keep them for now. The four output tubes that you currently have are 6550 tubes made by Svetlana. They are decent Russian tubes. However, current premium made in China tubes have really improved in quality. Both myself and my friend who has the 11A use some of the top of the line tubes made by the company Psvane. We both use the KT88, more of less a direct equivalent of the 6550. There are generally more KT88 than 6550 tubes made these days. Russian tubes generally currently come out of the same factory I believe, and are branded various names like "Gold Lion" or "Mullard" after the names of tube makers of fame from the past but they are nothing like those tubes.Having used some of these USSR tubes in the past, I generally have preferred the current premium Chinese tubes. All personal preference of course. There are also what are called NOS (New Old Stock) , old production tubes made in the heyday but now at very lofty prices due to their rarity. So there is your basic tube primer related to your amp. Have fun. Hope I have not overwhelmed you! |
@alvinnir2 thank you for the information! I'm currently using Linlai E-6SN7 tubes in my LTA preamp. I've also used various NOS tubes, but none of types that the Premier 11A requires. |
