Which of my Boogie 6L6s to Use?

[gtrrhythm]

Hi I have a Dual Recto Solo Head using Boogie 6L6's. I'm taking two power tubes and one Recto tube out to make it 50W. I have the following matched sets of Boogie power tubes available, and want to put in the two that will "overdrive" the easiest:

All are 6L6s, and STR 420's

06 NG GREEN
03 SK GREEN
50 NG RED
23 GR RED
older more rounded shaped ones - 6L6 GC (02 SK BLU)

Can anyone tell which two would work best? Thanks!

GTRRHYTHM

 

[mikey383]

I don't remember for sure, but I think the Mesa colors go by the color spectrum, with blue being the "coldest", and white being the "hottest". Meaning the blue coded set would breakup at a lower volume. There's a thread here somewhere about color coding and breakup.

According to Mesa, their tubes are all the same and don't breakup at different volumes, but we all know that can't be true. Otherwise, there would only be one color code for tubes.

 

[MrMarkIII]

According to Mesa, their tubes are all the same and don't breakup at different volumes, but we all know that can't be true. Otherwise, there would only be one color code for tubes.

Dont'cha just love conspiracy theories?
Groove Tubes has color codes which define different breakup modes. Somehow, their system has become conflated with Mesa's, when actually they have nothing to do with each other.

 

[mikey383]

According to Mesa, their tubes are all the same and don't breakup at different volumes, but we all know that can't be true. Otherwise, there would only be one color code for tubes.

Dont'cha just love conspiracy theories?
Groove Tubes has color codes which define different breakup modes. Somehow, their system has become conflated with Mesa's, when actually they have nothing to do with each other.

Doesn't GT have the number system instead of color codes...like 1 - 10?

I've seen where Mesa says GT tubes rated between 4-7 won't void the factory warranty.

 

[gtrrhythm]

Hey thanks for the replies.

Looking at a bazzillion threads in this and other forums, this seems to be a topic that noone can get a solid fact about. Some say the mesa boogie color codes are just to match tube sets, which would make sense, BUT, why then are there also # and letter codes (06 NG GREEN) in front of the color codes? They gotta mean something, right?

I also am beginning to wonder if how the tubes are arranged makes a difference. Where I'm taking out 2 tubes to drop from 100W to 50W, I know that I need to put the matched set in either the 2 middle sockets or the 2 outer sockets. Butr is there a difference? ALSO, I know I needed to take out 1 rectifier tube. BUT does it make a difference which of 2 sockets I leave the 1 remaining one in?

Looks like I may be spending a lot of time trying every tube / socket combination to see if I notice a difference.

Thanks again for your responses. Keep them coming out there - we'll figure this out yet.

 

[mikey383]

It doesn't matter which socket set you use. Both the left sockets are wired in parallel to one side of the output transformer, and the right sockets are wired to the other side of the OT.

Also, you don't even need to pull a rectifier tube. If you're using diodes, it won't matter anyway. If you are using the tube rectifier, the only reason to pull one of them is to keep the same amount of sag that you would get when using all the tubes. It's not going to do any harm if you leave them both in place, and you'll get a tighter tone. But if you want to pull one, it doesn't matter which because they're wired in parallel, not assigned to a certain pair of tubes.

 

[gtrrhythm]

Great information Mikey - thanks. Good to know I can get the tighter tone if I put that 2nd rectifier tube back in, as I do set to tube rectifier.

On the socket order, there's another issue that there are numerous opinions on - almost all threads out there on the subject say the 2 inside ones work together, as do the 2 outside ones. Go figure.

Thanks again!

 

[mikey383]

Great information Mikey - thanks. Good to know I can get the tighter tone if I put that 2nd rectifier tube back in, as I do set to tube rectifier.

On the socket order, there's another issue that there are numerous opinions on - almost all threads out there on the subject say the 2 inside ones work together, as do the 2 outside ones. Go figure.

Thanks again!

That is correct....they do work together in that manner. I'm sorry if my last post came off confusing...you always want to pull either the inner pair or outer pair, not the left pair or right pair.

What I was trying to say was that the left and right pairs are wired to different sides of the output tranny (which is why you want to pull one from each side, so it balances out)...say, the left pair of tubes sends part of the signal to the output transformer, while the right pair of tubes sends rest of the signal to the output transformer, where the signals are combined and sent to the speaker. Which is why it doesn't matter if you pull the inner pair, or the outer pair. You'll get the same results either way, assuming everything in the amp is in working order.

In a nutshell, just pull the inside pair or outside pair and you'll be safe. If you want less sag from the tube rectifier, put the second recto tube back in

 

[droptrd]

Either way there isnt much power tube breakup to be had in a DR. You have to really krank the thing. Im no expert in amp design but it seems to run really clean unlike my marshall ive had in the past.

 

[gtrrhythm]

Thanks Guys - all good info. Mikey, I see what you're saying now about the parallel setup of the right and left pairs of sockets.

I probably never will have a chance to truly crank this thing - just joined a band that keeps it pretty quiet in rehearsals. The days of cranking stacks are gone.

I threw the 2nd rectifier tube back in and threw an older pair of the 6L6s (blue) in the outer sockets. Sound is pretty good - a little more classic rock - which is what I'm looking for. The difference may be all in my head, but I'd swear those blue tubes are different than the 1st greens and reds I tried. Not done yet, will probably try the the other set of greens too just to see if I hear anything different.

Thanks.