Mark III - power tubes with 34's?

[jerry62]

The 2nd version of the Mark III manual suggests that using EL34's in the outer sockets will be a safer route (or something along that line)... is everyone doing this, or do most people stick with 4 6L6's? For decades I just used 4 6L6's, but I was just curious about the impact users have experienced having the 2 EL34's. I did briefly try some JJ 84's (edit, i thought they were 34's but they were 84s), but I believe I was experiencing tone issues before that (a good number of years ago), at which point I purchased a Lone Star 2x12 combo, which I've always struggled with attempting to dial in what I like.

 

[MrMarkIII]

I've had EL-34s in the outer sockets of my Mark III since I bought it new in 1990. That's the way Simul-Class amps normally came from the factory. I have tried 6L6s there, with no problems, but prefer the sound of the 34s.
My best info is that Mesa recommended only EL-34s in those spots for several years because of general tube quality control problems at the time.
The crappy 6L6 s of the time couldn't handle the hotter Class A sockets.
"Tone issues" would happen with the 6L6s, not the El-34s.

 

[daveg62]

Mine originally had all 6l6's. I changed to el34's in the outer sockets and prefer that over the 4 6l6's sound-wise anyway.

 

[jerry62]

That's interesting, thanks for the replies.

I believe the dealer let me try out the different configurations for a couple days in 1986 when I bought it and I went with all 6L6's (Original Mesa Marked 415's), as I preferred that tone actually. Received many compliments with that tone for a good 15 years.

I don't recall exactly why, but I last put JJ EL84's with yellow jacket converters in the outer sockets, probably from something I read online about 10 years ago. I put what I recall as a very high rated Svetlana 6L6GC (edit) in the other sockets, but wasn't happy with the results. [edit] Truth is the big problem with that setup was getting a balanced volume when switching modes... couldn't get it right, which is one reason I wanted to switch to multi-channel all with independant controls.

 

[Neptical]

EL 34s all day long for the outter sockets as it adds a very rich top end that compliments and breaks up the deeper side of the 6L6's. Actually, I've been playing and recording quite a bit these days just in Class A mode as the amp sounds devistating just pushing the EL34s. Punchy and sweet..and plenty loud enough as well. If I could use all 34s I probably would.

 

[Rhoads]

EL34 for sure! EL34 gave me a little crusty in my sound !!!

 

[mesaboogie6L6]

I've tried, 34's, and 66's in simul, tone is good, but it's too thin for me, the power drops 30 watts as well.......headroom!

 

[jpdennis]

According to Mike at Mesa he feels the EL34s are better for tube life; he did say they found this out over time. So, I would guess that 6L6s in the outer sockets aren't a problem, just not going to last, possibly, as long as the El34s if all you do is use the simil-class feature. Still since it is a similclass, it would be interesting to see if my Mark would do O.K. using the inner pair at a green Mesa rating and the outer at a red Mesa rating; I have read in this forum that you don't need to match all four tubes in a sumilclass just the socket "pairs" have to be matched.

Dennis

 

[gts]

According to Mike at Mesa he feels the EL34s are better for tube life; he did say they found this out over time. So, I would guess that 6L6s in the outer sockets aren't a problem, just not going to last, possibly, as long as the El34s if all you do is use the simil-class feature. Still since it is a similclass, it would be interesting to see if my Mark would do O.K. using the inner pair at a green Mesa rating and the outer at a red Mesa rating; I have read in this forum that you don't need to match all four tubes in a sumilclass just the socket "pairs" have to be matched.

Dennis

Yes just match the pairs in the inner or outer sockets not all four need to be matched.

The 2nd version of the Mark III manual suggests that using EL34's in the outer sockets will be a safer route (or something along that line)... is everyone doing this, or do most people stick with 4 6L6's? For decades I just used 4 6L6's, but I was just curious about the impact users have experienced having the 2 EL34's. I did briefly try some JJ 84's (edit, i thought they were 34's but they were 84s), but I believe I was experiencing tone issues before that (a good number of years ago), at which point I purchased a Lone Star 2x12 combo, which I've always struggled with attempting to dial in what I like.

I believe this tube issue is true based on the quality of the tubes made today.
The older STR-415's (Sylvania 6L6's) could handle the voltages of the outer sockets much better.
They were a better made and heartier tube than what's out there today with perhaps one exception:
Svetlana "Winged C's" are a very good 6L6 and can handle being in the outer sockets of a Simul. They might even be close to the old 415's specs.

 

[megavoice]

Well, it's very interesting to read that Mike B. said EL34s would be better for long-life resistance in the outer sockets.
I've had this issue told to Tien Lawrence after reading a obviously non-Mesa user-manual published in the net.
So he replied that their President had a statement about this not long ago as he said we can use unworried and 100% both 6L6 and EL34 in the outer sockets.

I by myself, I'm using exclusively EL34 in the outer sockets since 1987 as I liked them most.
But now after I've got a second Mark III also "redstripe, and it came along with 4 6L6, I feel that they sound also great, but different.
I've also to add that those power-tubes from the second are all labeled as AEG and the preamp have been "TESLA".
As a try I put all the same in the second-one like they are in the first and they sounded both identical after.

 

[benjamin801]

I've had a Mark IV and two simul-class Mark IIIs, and have always preferred EL34s in the outer sockets. My personal preference is JJ EL34s, but I'm not that horribly picky about power tubes.

 

[swbo101]

I've had a Mark IV and two simul-class Mark IIIs, and have always preferred EL34s in the outer sockets.

+1

I own a Mark IV and mostly run EL-34's in the outer sockets. Though I have from time to time run all 6L6's just for a change in sound. The 34's I've liked are the SED =C= and also Mesa's STR-450, the NOS Siemans.

 

[kdorsey]

EL 34s all day long for the outter sockets as it adds a very rich top end that compliments and breaks up the deeper side of the 6L6's. Actually, I've been playing and recording quite a bit these days just in Class A mode as the amp sounds devistating just pushing the EL34s. Punchy and sweet..and plenty loud enough as well. If I could use all 34s I probably would.

+1
I went all Class A for gigging a couple of months ago and love the hell out of it. If I needed much more volume, it would over saturate for my needs, but as is, it's fantastic. And with the new WGS speakers in my Boogie cab, it's fan-freakin-tastic.

Back to topic, mine came with all 6L6s from the factory and I had to buy EL34s. It has been back to all 6L6s only a couple of times in 23 years but will probably not stray from EL34s ever again.

 

[Neptical]

EL 34s all day long for the outter sockets as it adds a very rich top end that compliments and breaks up the deeper side of the 6L6's. Actually, I've been playing and recording quite a bit these days just in Class A mode as the amp sounds devistating just pushing the EL34s. Punchy and sweet..and plenty loud enough as well. If I could use all 34s I probably would.

+1
I went all Class A for gigging a couple of months ago and love the hell out of it. If I needed much more volume, it would over saturate for my needs, but as is, it's fantastic. And with the new WGS speakers in my Boogie cab, it's fan-freakin-tastic.

Back to topic, mine came with all 6L6s from the factory and I had to buy EL34s. It has been back to all 6L6s only a couple of times in 23 years but will probably not stray from EL34s ever again.

Right on! The more I play Class A live, the more I love it. The tone pushing the 34s is heavenly sweet. Tell ya, for a 15 watt mode..it's still mega ear shattering. Thing is, the louder you crank these amps,the sweeter and richer they sound..so you haven't lived yet until you've cranked these amps hard.

8)