Tube Rolling

[jhawk92]

Ok, all you valve fans out there, how do you go about comparing different types of tubes in your amps? I have my 299B and have been using the Sovtek 7189s that Craig put in, but I still have the original set of 7189 Telefunkens that I'm thinking about rolling in there to see how they sound. Trouble is with the 299B, you have to wait about 30 min to bias the tubes after you put them in. Granted, listening to them while they warm up is probably pretty close to how they will sound, but it's not an optimum solution. I guess you could run one speaker with the Sovteks and one with the Teles.

Since my music "memory" isn't all that long, I'd really like to be able to swap tubes on the fly, but I don't think it's advisable to pull tubes out once they are hot. So you wait 3-5 min for them to cool, then swap out, and start the music over again...not the best way to test. I suppose the easiest is to have monoblocks and then set up each with different tubes, then just see how they sound. What do other folks do?

Also, I know Mullard is a great NOS tube, but I'm seeing some new Mullard tubes out there, so I was wondering how they compare to the old ones? I'm specifically looking at the EL34 tubes, wanting to compare how the Mullard, JJ Tesla, and some of the other brands sound, say EI, Sovtek, etc. I know each amp can sound different, but in general, are certain tube brands better than others? Mike Sanders at Quicksilver really likes the JJ Tesla in his amps, but those Mullards are intriguing. Thanks.

Rob

[Tonga]

Rob-

May I offer a suggestion ?

Maybe when you listen to brand " A " tubes , keep a pen and paper handy and write little comments on the paper throughout the night while you listen to various types of music on your system. The next night, try brand " B " tube and again, jot down notes as to what you hear and dont hear while listening.....compare the notes and see what you like and dislike with a certain tube.

As for the EL-34....Currently , I am using the "Flying C" in my Dodd Amps and like them very much. While there are others tubes out there, I havent had the chance to sit down and figure out which ones I would like to get next. The good thing about EL-34 Tubes for the most part, is that they are very cheap compared to the 6550 or kt-90 power tubes. Of course it depends on how many tubes you need also ! I have a friend that has a pair of Wolcott tube amps, and those take 8 EL-34'S in each amp, so retubing that can be expensive to say the least ( for me anyways !)

Good luck and have fun.

Brad