how often do you replace pre-amp tubes?

[xshawnxearthx]

just wondering.

havent done so in a few years and now i'm getting this wierd noise when i used my E string to -play the E and F notes.

 

[nonsqtr]

I generally replace preamp tubes every year. That's just me though, it's probably completely unnecessary, unless you're using your amp "a lot" like I do. I like to keep them fresh, and fresh-sounding. The difficulty with that approach, is that replacing a preamp tube tends to change your sound a little, perhaps in ever-so-subtle ways, but one tube is never like another (at least that's been my experience). The chances of getting two tubes from the same manufacturer to sound "identical" are practically nil. The question is, "does the difference matter"? In my view, I'd rather have "reliability" (ie new tubes), than risk a preamp tube going bad in the middle of a gig. I've used all kinds of tubes, modern production tubes like JJ's (which I really like), and vintage tubes like Telefunkens and so on. I have a whole big box of old Telefunkens that probably work fine, but they're out of my rig 'cause they're just "old". The number one criterion in my book is "reliability". Sound is second to that. Most people won't even notice subtle changes in sound, but they'll sure notice when your rig dies in the middle of a gig.

 

[xshawnxearthx]

yeah so its safe to say i should replace them if i have not in a few years. i dont know. its wierd. when i first got my new p-bass in oct, it sounded sweet. now all of the suddens its not sounding so sweet, and i think its the tubes. hopefully.

 

[Psycho Bass Guy]

Unless your amp quits passing sound, you should NEVER need to swap a preamp tube if it's of decent quality.

 

[Jerrold Tiers]

I generally replace preamp tubes every year. That's just me though, it's probably completely unnecessary,

Yep, it IS unnecessary

unless you're using your amp "a lot" like I do.

Doesn't matter.....you'll know when you need to....eventually....like several years or more.

In my view, I'd rather have "reliability" (ie new tubes), than risk a preamp tube going bad in the middle of a gig.

That just about never happens.....unless you drop the thing down stairs. They "go bad" slowly, losing gain very slowly over a long time.
Sometimes they may get gassy very slowly if rough handling cracks a seal a tiny bit.

If they work at sound check, they'll last the night as well as any other part of your amp.

I've used all kinds of tubes, modern production tubes like JJ's (which I really like), and vintage tubes like Telefunkens and so on. I have a whole big box of old Telefunkens that probably work fine, but they're out of my rig 'cause they're just "old". The number one criterion in my book is "reliability". Sound is second to that. Most people won't even notice subtle changes in sound, but they'll sure notice when your rig dies in the middle of a gig.

MMMMMMMmmmmmm.....wanna sell all those "old" Telefunkens? Going cheap, of course, cuz they're "old and bad" now.

 

[brianrost]

I change them if they start getting microphonic or otherwise malfunction.

I have some ancient tube gear with the factory preamp tubes....30-40 years old