Swapping tubes in and out, dumb question.

[rockanomicon]

Is it possible to swap tubes in and out preamp tubes and power amp tubes, without causing damage to the tubes or amps (provided they are handled correctly etc....)
For instance say, one week I want to run EL-34's....the next switch over to 6l6's. And/or swap various different preamp tubes in and out of various positions in the search for "the tone".

 

[theroan]

Depends on many factors.

Does the amp take different tubes (Like a Mark IV)

Pre-amp tubes can be switched in and out with no problems in terms of brands, but you have to use the same kind of pre-amp tubes. So you can use any brand but your amp take 12ax7's you have to use those only.

Power amp tubes are different, tubes have to be "set-up" for the amp they will be used in. So more Mesa, you can swap out el34's, 6L6's or 6V6's in a Mark IV everyday SO LONG as they are all MESA brand tubes. Other tube brands may not be set up for the amp you are using and could break and void your warrantee. So Fender to Mesa wont work. But most tubes stores online or whatever will calibrate your tubes for the amp you use. So order tubes of whatever kind you want from www.tubestore.com and tell them in them in the comment section what the make and model of your amp is so they can set your tubes for you amp. So dont just borrow your buddies tubes and mess around, you could do serious damage to your amp. But thats if your amp is designed to take other tubes, if it's not then dont even try. Either way, this could end up a very expensive experiment.
Hope that helps.

 

[212Mavguy]

Hi Rockanomicon,

What kind of amp(s) are you interested in swapping out tubes in?

You can find quite a few posts in this section of the forum describing successful tube swaps for preamp tubes other than 12ax7 in mesa amps that have the same pinout as 12ax7 for certain preamp tube positions.

As far as voiding the waranty, that is true. My mesa is way out of warranty and it has nary a mesa tube or speaker in it. Now it sounds more like a "Mesa" in my opinion than when it was new.

Mesa amps do not come with user adjustable power tube bias due to the philosophy of the company founder. Again, here, the more informed an owner is, the more choices for power tube selection are available...especially after the warranty expires.

A few users, such as fellow member (and amp tech) Stokes will install bias adjustment pots in their mesa amps, that allows more tonal fine tuning and tube selection in the power section, but again, the more that the amp owner knows, the better off he is. For the vast majority of Mesa owners the Randall Smith philosophy is by far the best, but not for all.

There are a lot of opinions, a lot of philosophies, and a lot of right answers in this forum. Peace.