EL34 vs. 6L6 in Mark IV

[swbo101]

Since the EL’s run hotter, is there a tendency for them to need to be replaced sooner than 6L6’s, given the same amount and type of playing? This is something that I've noticed, but it may just be my impression. Also is there more of a risk of a EL harming the amp if a tube fails compared to a 6L6? Finally,how does the circuity of a mark iV know which tube is in use since there is no EL34, 6L6 switch? Thanks

 

[Scrapinger]

I've not had an issue with EL34's, other than Mesa labeled power tubes. I had two go bad right close to each other as well as 3 out of 4 of the 12 ax7's that were in it to start with. Sent the head in and it checked out fine. I run Tung Sol power and preamp tubes and have had NO issues what so ever.

 

[yfeefy]

In terms of bias idle heat dissipation EL34s don't run hot in a Mk iv they run pretty cold, even in those outer sockets., which, although hotter than the inner ones, are still designed for 6l6.

 

[swbo101]

Thanks for the info. I actually found this really good article from the Boogie site detailing those differences. Thanks again.

http://mesaboogie.com/news/2010/08/6l6-vs-el-34-feel-the-power-of-your-amps-power-section/

 

[droptrd]

The IV sounds pretty bad *** and in your face with all 6L6s if you are worried about EL34 failure

 

[swbo101]

The IV sounds pretty bad *** and in your face with all 6L6s if you are worried about EL34 failure

Yeah I know...I just put 4 6L6's in..but I like the EL-34 sound. Especially in Class A with a Les Paul. Softens the sound a bit..not as modern sounding. The 6L6's sound better with my Strats though. Can't complain either way.

 

[droptrd]

Ive been running JJ E34Ls on all my 34 amps for a while now. Ive had very good luck with them. knock on wood :lol:

In most cases theyre lasting longer than my 6L6 amps. Like my 5150. That thing eats tubes. So maybe it depends on the amp?