Question:
I was wondering what kind of change in tone would i get if i put EL-34's in the class A sockets in my mesa. Right now it has 6L6 in it. Thanks for the help
Answer:
Originally Posted by wesley7777 I was wondering what kind of change in tone would i get if i put EL-34's in the class A sockets in my mesa. Right now it has 6V6 in it. Thanks for the help
Only one way to find out I believe that its the break-up/distortion characteristics of power tubes that makes them different. If you can't turn the amp up loud, say the master volume is turned down to like 4 maybe, you probably won't hear much difference. Even if you are using distortion from the preamp or a pedal, with the master down, the power tubes are just cleanly reproducing what is fed into them, much the same way as a solid state power amp. If you are able to play it cranked up , since 6V6's are maybe 1/3rd the potential output power of EL34's, probably the most noticable change will be more clean headroom; the amp will be louder before any power tube saturation occurs. If you're able to push it into real power tube distortion, I don't have a clue what tone difference would be. If its a 1x12 combo, the speaker may reach saturation before the power tubes do...
Which Mesa do you have?
Answer:
Originally Posted by Major Tom Only one way to find out I believe that its the break-up/distortion characteristics of power tubes that makes them different. If you can't turn the amp up loud, say the master volume is turned down to like 4 maybe, you probably won't hear much difference. Even if you are using distortion from the preamp or a pedal, with the master down, the power tubes are just cleanly reproducing what is fed into them, much the same way as a solid state power amp. If you are able to play it cranked up , since 6V6's are maybe 1/3rd the potential output power of EL34's, probably the most noticable change will be more clean headroom; the amp will be louder before any power tube saturation occurs. If you're able to push it into real power tube distortion, I don't have a clue what tone difference would be. If its a 1x12 combo, the speaker may reach saturation before the power tubes do...
Which Mesa do you have? I have a mesa Mark IV combo 1x12. See i am trying to go for more of a british type amp tone, maybe voxish( though they use El-84) or Marshalls.
Answer:
I would first check to see how much of an issue the bias change would be . Many amps have a switch so you can use both 6L6`s and EL34`s. This will get you in the ballpark but the amp MUST be biased on a bench or you risk at the least tube if not amp damage . I suspect you have a 6L6 amp but if it is indeed a 6V6 you will have to swap components most likely to bias it for EL34`s.
FYI 6L6 is a tighter tube with more headroom with a lot less mids than the EL34. The EL34 is going to have more mids and be softer in feel with more compression than a 6L6 all things being equal.
Answer:
Originally Posted by shreadhead I would first check to see how much of an issue the bias change would be . Many amps have a switch so you can use both 6L6`s and EL34`s. This will get you in the ballpark but the amp MUST be biased on a bench or you risk at the least tube if not amp dammage . I suspect you have a 6L6 amp but if it is indeed a 6V6 you will have to swap components most likely to bias it for EL34`s.
FYI 6L6 is a tighter tube with more headroom with a lot less mids than the EL34. The EL34 is going to have more mids and be softer in feel with more compression than a 6L6 all things being equil. Well it says in the book that changing them out will be no problem and the amp is self baising so that doesn't seem to be any problem.
Answer:
Originally Posted by wesley7777 Well it says in the book that changing them out will be no problem and the amp is self baising so that doesn't seem to be any problem.
Does it have switch settings for the different tubes? I'll have to see if I can find a schemo for that one, I know there's a few amps out there that are engineered to accept different power tubes, but there should be a switch setting or something to go from 6V6 / 6L6 / EL34 types, as they draw different amounts of current.
Answer:
I just looked at a schemo, in the text it states it lists either 6L6's or EL34's, doesn't mention 6V6's. If it has 6V6's in there, unless there was a later version of that amp, my guess would be that it was modded for the 6V's, in which case putting EL34 or 6L6 back in there would require some un-modding for it to sound right; otherwise the bigger tubes won't be biased for enough current and probably won't sound good. The is a "simul-class / class a switch" in there, should be on the back of the amp - I'm not sure but that may need to be in one position or the other for a specific tube type, should say in the owner's manual if you have one. I'm not sure about the biasing either - most amps that say "self biasing" I think are usually cathode biased, meaning there is no bias setting like "fixed bias" amps to adjust to the individual tubes current draw. I'm missing part of the schemo, but from what i can tell its not cathode biased - but the part I'm missing is the bias supply schemo... + I don't grok the simul-class switch thing, and to boot, I'm a hack Do you have a manual?
Answer:
Originally Posted by Major Tom I just looked at a schemo, in the text it states it lists either 6L6's or EL34's, doesn't mention 6V6's. If it has 6V6's in there, unless there was a later version of that amp, my guess would be that it was modded for the 6V's, in which case putting EL34 or 6L6 back in there would require some un-modding for it to sound right; otherwise the bigger tubes won't be biased for enough current and probably won't sound good. The is a "simul-class / class a switch" in there, should be on the back of the amp - I'm not sure but that may need to be in one position or the other for a specific tube type, should say in the owner's manual if you have one. I'm not sure about the biasing either - most amps that say "self biasing" I think are usually cathode biased, meaning there is no bias setting like "fixed bias" amps to adjust to the individual tubes current draw. I'm missing part of the schemo, but from what i can tell its not cathode biased - but the part I'm missing is the bias supply schemo... + I don't grok the simul-class switch thing, and to boot, I'm a hack Do you have a manual? NO it has 6L6's in there. I wondered were yall were getting that from, then i noticed in my first post that i made a typo and put a V when i meant an L. I am a real genius aren't i. I feel stupid. Alright so moving on, thanks for the help guys.