290 with E34L/6L6 combo: first impression

The Boogie Board

Help Support The Boogie Board:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Sep 30, 2012
Messages
20
Reaction score
0
Hi all. I have been following the topics about the use of EL34s in my mesa 290. I have a pre 2000 one (Mesa checked it ouot for me with the s/n), blue pilot light.

Mesa provided me the position where the E34L should go. in my case they go to the sides. I bought a JJ kit for the 290 and put it just minutes ago. FYI, the previous kit was a ruby 6L6s.

I had an amp technician with me while changing them and he could do some generic measurement which though are saying something.

For example: the rubys showed a measurement of 30 milliamps while the 6L6 JJ showed a 37 milliamps current passage.
The E34l, though where surprising: they showed a measurement of 10 milliamps which practically tells us they virtually don't work.

My mesa don't have the chance to switch for the use with e34l or 6l6. there is none inside the amp. so all I could do was to put the tubes as mentioned above.

as for sound............unfortunately i cannot do a real comparison with the previous tubes since I turned on the amp after putting the JJs. I notice though that the volume has going down (probabily because the E34L are almost not working). this thing though has a huge advantage: To get the same volume I had before, with the rubys, I must turn the 290 up to 12 hours. with these volume the amp rally starts to take life. Prior the volume was so ridiculous that no club would allow me to keep it at such level.
Now, the mesa is somewhat warmer due to the fact that I can have its volumes high enough.

since the volume is turned fairly up, I got another advantage. prior to the tube changement I always had the deep extent on. it is a nice feature but the thump is so huge that with low strings it makes the guitar unusable.

with the new tube set up, with the volume at 12 oclock, I had to turn the deep extent off but to my surprise the sound was excellent. All I had to do, to compensate the loss of deep was to add some bass to my pre amp (a kemper profiler).

Overall, my tech said that he found not usefull to use the el34 if they work so low in milliamps. maybe the 290 with the el34/6l6 switch can make the el34 work.
The sound though is very good because, as said, the amp is brought to life with the volume set high.

in the next days I will test the 290 by taking out the el34 and put some of my previous rubys back in their places to see if there is a change. my rubys are praxctically new because I put them in my 290 and barely never used it but since the last year on.

of course, the 6l6/el34 has a definite earlier breakup compared to all 6l6, but this is due to the fact that the volume has dropped. my tech says that my 290 erogates now something around 50-60 watts per channel. it is a rough estimate that he promised he will make sure by testing it with proper instruments.

that is all.

hope this report can help.

all the best

michael
 
That's interesting . I just picked up a 2:90 after having a 50/50 for 13 years , along with a Triaxis . I am also interested in the EL34 option...I have been interested in the older rack Boogies like the 295 ...which is a monster ! 4 rack spaces , but one of the features is that it has 2 6L6 and 2 EL34's per side....So after so many years of playing (since 1973) I found the 2:90 and shedded almost all my pedals . The headroom is so big. Anyway I had some extra cash ...so I just now bought a 295 and a Quad in a rack , off of Ebay. So I will update how the 295 sounds compared to the 2:90. I should have it in a couple weeks.
NOTE to all Ebayers ....very important when you buy a tube amp , to have them pull out all the tubes and wrap them in bubble wrap and secure them . I got my 2:90 off of Ebay and the guy did not wrap them and ALL OF THE TUBES FAILED. I never had any problem with any amp until I got the 2:90 . USPS threw it around and bent the rack ear and wella the tubes failed and it burnt the filament , also . So that's another reason why I purchased the 295 and Quad . I can't wait. I'll let you know in a couple weeks !
 
Interesting with 2:90.....
I also run an integrated set of 6L6/EL34 (Tungs Sols) and there is no drop in power or volume or whatsoever...just pure SimulClass godness
 
hi Triaxstasy,
have you tried to measure the current passing from your el34? since I see in your signature you have a 290 with blue pilot light, I guess your is like mine, having the el34 at the sides of each channel...........
 
...sorry, no chance of taking any measurements at the moment.
My understanding of the the layout/config is that the inner sockets run in AB with a max power of 30w per (6L6) tube whereas the outer sockets operate in class A with max power of 15w per (6L6) tube giving the amp 90 watts (60 AB plus 30 A) per side if the tubes were biased at 100% dissipation. Since that would be ultra hot and we all know that the MB-typical fixed bias is rather cold that imho explains some of the readings....
Experts please chime in....I`m mainly a "user" ;-)
 
me too: I'm a user as well. and would like some of the wisest and best acquainted with the thing to join us.
 
I have a combo of the two in my 2:90 as well and I really like it. Mine is the older blue light version and I believe I have the EL34s in the outer sockets. I'd have to look at the diagram that I have. At any rate, I think it sounds really good.
 
Hi Mark....and bests for the upcoming end of the year :)

I have to say that indeed it sounds good. but I have done some research about this issue. Here's what Mesa Boogie it self replied after I enquired for the matter.

for better understanding I paste my question as well. in Italic Mesa's answer.

I own a 290 pre 2000 production and wanted to instal a 6l6/el34 combo on it. Marcus (Daniel) emailed to me a picture for tubes correct placement. While measuring with a multimeter the current passing from the 6l6 tubes we have measured something around 37 milliamps, while the current passing from the EL34 are only 10. Do you reckon this fact? The fact that the el34 have such low current means the amp have a sensible lower volume compared with all 6l6. The sound though is fantastic and as an advantage I can use the 290 at 12.00 o’clock letting it be alive. never couldn't with all 6l6 because of the outrageous power.

Thanks for all the help and advices you can give me.

Michael

Hi Michael,

Yes, those readings seem correct.

However, we are now recommending to not use EL34's in the 2:90 - as the filament current is higher than we would like to see for EL34's. We recommend ALL 6L6's...

Please let me know if you've got any questions or need assistance in any way. Thanks!

GN


I guess this sheds a definitive light over the thing. or at least, since Mesa comment can be considered being a party one, my final statement is the following:

the 290 can use both the configuration, all 6l6 or 6l6/e34l, both having advantages and disadvantages.

290 with 6l6
advantages: use of the 290 as it was designed - outrageous power (when there is a need to play in a coliseum)
disadvantages: as a guitar player, the majority of the times I had a gig I had to keep the volume at 10:00 oclock (at the most) keeping the 290 asleep, in a way, thus the sound is a bit slobby

290 with 6l6/el34
advantages: since my 290's el34 have a low current passing on them, the overall volume has decreased sensibly making the 290 able to be used at 12 o'clock thus making the 290 alive: now it sounds as it wants to sound!
disadvantages: a bit of power has gone so this can make the 290 not suitable to huge volumes. it can be used at higher volume than 12 but the early breakup can make it hard to achieve a crystal clean sound especially with humbucker pickups

the above mentioned statement is just my experience based on me ear and based, as said in my first post, on the measurement of the current passing from the E34L sockets.
I would be curious to know the measurement of the 290 owners with 6l6/e34l combo. In fact it is safe to say that I cannot be the only one having such low current passing from the e34l. I tend to say it is the amp architecture that does it. so the other 290 should behave the same, as Mesa guy stated.

all the best to everyone

michael
 
Back
Top