6L6'd only in Mark III?

[Mellowtronic]

Hey all,

Just got my Mark III blue stripe. Has simul class. I like running it Class A a lot for this latest project I'm working in. However, I was wondering if I can throw 6L6's in place of the El34's, so as to run 4 6L6's while running simul class, and 6L6's while running Class A.

 

[Restless Rocks]

Yes!

 

[Mellowtronic]

Awesome. I'm glad no one started flaming me for only wanting to use 6L6's. El 34's are cool, but they just don't have that round bottom end clarity I seek.

 

[Boogie Woogie Man]

Depending on what mood I'm in, I often run 4 6L6's. As you say, they have a smother bottom end. Sometimes I just want that EL34 sound so I just change it. That's the beauty of these incredible amps, very versatile.

 

[Whoopysnorp]

I also have a Mark III blue stripe and I think I'm going back to four 6L6s. I am having a hard time getting a clean that I like with EL34s in the outside sockets.

 

[Mellowtronic]

Yes! There's something very Fender Ice Pick about the El34's. It's not as harsh, but it does not have that fat fat clean I've gotten from my other Mesa's using 6L6's only.

 

[Mellowtronic]

Could I also throw KT88's in the other sockets? In all four? Middle two?
Thoughts?

 

[kmanick]

How does this work without hurting the amp?
isn't the plate voltage on an EL34 different from a 6L6?
I'm running El34's in the outer pair of mine, and I'd like to try all 6L6's but I'm horrified that I will damage my baby.
can someone please explain this to me (it seems like a very cool feature).

 

[acorkos]

How does this work without hurting the amp?

you won't hurt the amp, but you may fry your 6L6s in the outer class A sockets. Mesa specifies only EL34's in the outer sockets because of tube reliability issues. Read about it in your manual....

http://mesaboogie.com/manuals/Mark%20III.pdf

 

[kmanick]

I saw that that's why I'm asking, I've seen other members on here state tey are running all 6l6"s???
I don't get it.

 

[kmanick]

thanks GTS
I saw your other post, thanks for putting it out there for us!

 

[acorkos]

Why they changed this in that online manual is best answered by Mesa.

it probably cuts down on their power tube warranty returns

 

[Anonymous]

Post removed.

 

[dodger916]

So I take it the plate voltage of the outer sockets is higher than that of the inner. Wouldn't that mean you could run EL34 in the inner sockets for a cold and sterile sound and have the tubes last forever?

The outer sockets run in Class A, which is harder on tubes.

 

[acorkos]

the plate voltage of the outer and inner tube pairs is about the same (within a couple of volts)....the outer tubes run a lower negative bias voltage which pushes the tube into class A operation