Question on Express 5 50+ Power Tubes

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JiJoe

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Been trawling through posts on this subject for a few days now - narrowed my questions down to a couple of things I can't get a definitive answer on from reading through the posts.
There's a lot of info of course but it takes a bit of picking through and is quite subjective.

I'm looking at changing power tubes - have stock tubes in an Express 5 50 + from 2013. Never changed them as they have always been fine.
Now just doing some rolling to see what I can get out of the amp.

I am looking at the following options and wonder if anybody has tried any of these tubes in an Express 5 50 + and have any thoughts on them in terms of how they changed your tone/feel.

1. TAD 6L6GCM-STR REDBASE - this is the long bottle type
2. TAD 6L6WGC-STR REDBASE - this is the short bottle type
3. Svetlana Winged C - 6L6GC - the 'winged C'

I also have a question about the Colour Rating - I have AC 10 GRY Mesa Tubes just now.
As far as I can tell it's not essential to find a Colour rating match - but it is more important to ensure that the pair is a matched pair.
So my question is - can anybody confirm this assumption or advise differently regarding the Colour matching issue?

I have an electronics background (although not old school vacuum tubes etc) - but just really looking for a basic steer on whether or not now power tubes really need to be Colour matched to the amp bias point.

I have been rolling some pre-amp tubes as well - using Harma and PM tubes that I had to hand. Let me know if you're interested on what I got out of that and I'll explain what I found.

Thanks in advance to anybody that can chip in with some thoughts.
 
Throw away the color code guide which only gets you sorta ballpark and don't assume they match. Check the mA on every tube if you want them to match. There is no way around that.

If this was a old Mark and the winged =C= are the true SED it's a no brainer. It's one of the only tubes made that can handle high plate V like a walk in the park.

440's work great in an express and =C= is overkill but the only list of tubes that has anything better is one with a choice of the STR 415 which is Mesa screen printing on a STR 387. Both the STR 415 and 454 are better served in an amp that needs the Vplate handling but there is nothing better.
 
Thank you very much indeed for your reply EM.
I am not sure that I understand what you were trying to tell me to be honest as I had never looked at STR numbers specifically.
It seems that they relate to special orders of Mesa tubes on a variety of manufacturers. This has added another dimension to the mystery.

Thanks again and all the best.
 
Yw.
STR 415 = mesa label on a Sylvania STR 387 - the one to rule them all
STR 454 = mesa label on a winged =C=, the best STR 387 copy ever made
STR 440 = 2 different tubes with mesa label, a EL34 STR-440 was made but more commonly this is a 6L6GC. I think this is the tube the Express came with originally and is a good choice.
 
Wow EH - that clears it up - thanks very much indeed for that.
All the best.

I'll report back here with what I end up doing and how it works out.

Cheers
 
Been trawling through posts on this subject for a few days now - narrowed my questions down to a couple of things I can't get a definitive answer on from reading through the posts.
There's a lot of info of course but it takes a bit of picking through and is quite subjective.

I'm looking at changing power tubes - have stock tubes in an Express 5 50 + from 2013. Never changed them as they have always been fine.
Now just doing some rolling to see what I can get out of the amp.

I am looking at the following options and wonder if anybody has tried any of these tubes in an Express 5 50 + and have any thoughts on them in terms of how they changed your tone/feel.

1. TAD 6L6GCM-STR REDBASE - this is the long bottle type
2. TAD 6L6WGC-STR REDBASE - this is the short bottle type
3. Svetlana Winged C - 6L6GC - the 'winged C'

I also have a question about the Colour Rating - I have AC 10 GRY Mesa Tubes just now.
As far as I can tell it's not essential to find a Colour rating match - but it is more important to ensure that the pair is a matched pair.
So my question is - can anybody confirm this assumption or advise differently regarding the Colour matching issue?

I have an electronics background (although not old school vacuum tubes etc) - but just really looking for a basic steer on whether or not now power tubes really need to be Colour matched to the amp bias point.

I have been rolling some pre-amp tubes as well - using Harma and PM tubes that I had to hand. Let me know if you're interested on what I got out of that and I'll explain what I found.

Thanks in advance to anybody that can chip in with some thoughts.
Either order a new pair from the Mesa web site, or Get yourself these boy, I wish I could get a set myself right now. Take your pick, offer 75% of asking https://www.ebay.com/sch/i.html?_fr...used+pair&_sacat=0&_odkw=6L6GC+used&_osacat=0
 
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