5150 Tubes

[StaceyB]

Hey there, just wondering if you could tell me what the best replacement tubes for a 5150 combo 212 would be? Also, is it ok to replace them myself or should i have a proffesional tech handle this so the amp can be biased as well?

Thanks

[edhead]

I would suggest going with JJ's 6L6GC's and EH 12ax7's in V1 and V3, with JJ's ecc83's in V2, V4, and V5. It's the best combo I've heard yet.

[Jerry P]

If the amp is stock the bias isn't adjustable and you should be OK just installing a pair of matched power tubes. It's a good idea to have a tech check the bias to be sure everything inside the amp is working at 100%. The bias circuit can be modified to be adjustable. This would allow a tech to bias the tubes up warmer to get a warmer fuller sound. The 5150 combo is biased warmer than the 5150 from the factory so your amps bias may be warm enough already.
JJ 6L6's are my favorite power tubes for the 5150's. I like EH, JJ, Chinese, and Sovtek LPS 12AX7 preamp tubes. They all sound a little different so sometimes you have to mix and match to get the tone you're after.
For 12AX7's, JJ's are a little on the dark side. EH are bright and cut thru nice, but all EH might be too harsh. The Chinese is a great all around balanced tube that cuts thru nice. Sovtek's are also on the bright side.
Check with Doug's Tubes for tubes. Doug is a great guy with great prices and he does an excellent job of testing and matching.
Jerry

[edhead]

Jerry...when you say Chinese...any particular brand?

[Jerry P]

Shuguang. I'm not 100% sure, but I think they may be the only company left making tubes in China. Doug's Tubes Check with Doug.
Jerry

[acdc126]

ill use shuguang kt66 when my mods will finished on my new amp, i wish it can sound a little bit better than 6l6. but my question is not exactly for the ouput tubes, do you know what is the AC high voltages of the 5150 power transformer.
thanx