My 5150 is starting to sound weird...
My 5150 is starting to sound weird...
I can usually get away with changing pre-amp tubes every other time I change power tubes, but I usually replace my power tubes every 6-9 months, with a lot of use. Except for the phase inverter tube (considered a pre-amp tube) that gets changed with the power tubes too. It will usually end up as a spare.
If the amp is over 1-2 years old and never been retubed, it probably needs all of them replaced.
Actually I cant reccomend specific tubes, however anything by ruby jj or groove tubes seems to get a lot of love, i'd avoid EH tubes like the plauge though..
Maybe you should give doug from dougstubes a shout he might be able to suggest what you need for the full set...
You may not need to replace the fullset of preamp tubes but if you are getting it done you mightaswell do it all at once...
JJ's are usually 'fine.' I've heard good (and bad) about the TAD's, but most have been favorable. No idea on the Mullards, but they seem to be rated pretty well. A lot of people (myself included) like S.E.D. tubes, considered to be 'the real deal' Svetlana Winged C's vs. the brand name Svetlanas. It has to do with who bought the name and such. I also like some of the Sovtek power tubes, like their 5881WXT.
For the most part, any decent brand should do just fine, but there are subtleties to be had in experimenting with different brands in different amps.
Tubes are (almost) always the first thing to try, especially when their age is suspect or unknown.