I'll see your bet and raise you with the Official Source (from Yorkville/Traynor's own website) vs those fan pages:
Those "fan pages" have been around much longer than Yorkville's "Traynor" section, and if you'll note the second link I posted was to a .pdf of the owners manual from Traynor.
http://www.yorkville.com/products.asp?type=71&cat=46&id=293#yba3
Further to that, there is absolutely NO mention of output tube types, but it does say that the YBA-3
A had double the power of the YBA-
3. How do you explain this feat using the same type of output tube?
Like I said, they may have changed the power section partway through the life span of these models, but the (arguably, few) I have seen or used were 6CA7. They're just too heavy and expensive for me to bother with.
The YBA-3A was designed from the ground up to compete with the Ampeg SVT (and it does quite well). I'll venture you've never seen one, only its similarly named smaller sibling, and thus, don't understand that it is a separate model and not some mythical "revision." The 6KG6 tubes actually have a slight green glow around the top plate cap under operation
You seem to not want to understand what I am saying but defend somewhat misleading categorical statements (and ignore accidental contradictions) you've made.
...and you have yet to grasp that I am speaking in broad generalities intentionally, and the information I am giving is correct while you fret over irrelavent minutae while making many categorically fundemantal incorrect statements.
Not all YBAs were Marshall based. Basically there was the YBA-1 and YBA-1A (also YBA-4 and YBA-5 which were the later combo versions of those same amps) and that's about it (if we're ignoring amps designed for/marketed as being for guitar). That leaves the YBA-2 (6V6), 2A (6BQ5), 2B (6BQ5) as having little Marshallness to them. ... and of course the YBA-3 and 3A which were kind of a Marshall/Ampeg mashup.
Let me put this a little more plain: I don't care. I could take you through the schematics and show how all the circuits, inlcuding the EL84 and 6V6 models, are still very similar to Marshall designs with only minor variation, but it would be a waste of my time as you would only try to find some way to cloud and prolong an issue that is only a minor point and not germane to this discussion anyway. It's clear that you like to throw around numbers and designations, and it's also clear that you don't actually understand what a lot of them mean, though you think you do.
Also: A Plexi is a guitar amp so why did you bring it up if that's how you feel about me bringin up the YGAs (which are used by bassists FYI, because its the same amp as the YBA-1 as mentioned) (< rhetorical FYI)
Marshall Plexis came in PA, Guitar, and Bass models, all based off the Bass (no pun intended) model.
Play fair, dude. It's not a competition for anyone to win or loose.
I'm not being competetive, just factual. If you don't like being corrected, learn what you're talking about.
I'm not trying to take your amp expert title away from you
There is no "title." The only competiton that exists is in your head and you have been very antagonistic, both to me and others, quite needlessly. I have absolutely NO doubts that if you had to do any actual work to a tube amp, you'd be completely lost and all of your internet bravado and stubbornness could not overcome the laws of physics.
nobody knows everything all the time and though you are very knowledgeable, and I appreciate that, you are not always the best at communicating that knowledge.
As I said earlier, I learned that much of my info must be simplified. In YOUR quest to expound my comments beyond that, you consistently post factually incorrect information and do so in an incredibly antagonizing manner. My days of writing near technical papers for the benefit of an anonymous internet audience are over. There is nothing that I have ever alluded to that some simple research cannot clarify for any interested party without me generating tomes that glaze over the eyes of the less technically inclined in the audience.
I was trying to fill in the gaps, but it appears that you took it personal.
There were no "gaps." My comment is accurate. Yours, however, are not. That's not personal.