Alright. So I recently picked up a YBA200 for the electric gig I have going on right now... When it comes to all instruments electric, I insist on tube heads, so the solid state upright rig wasn't cutting it. My chief complaint with the YBA was similar to others I've read here and elsewhere. Not enough volume. Not enough clean headroom -- too dirty too early. Not enough BALLS. My first inclination was to re-tube the power section with KT88s to replace the high-output, yet gain-y stock Sovtek 6550s. Well, I'll probably still get around to that, but I've already come up with an easy an inexpensive way to up the headroom with minimal expense... I replaced the stock 12AX7s in the preamp; I now use an E-H 12AY7 in V1, and a NOS Mullard 12AT7 in V2. V1 will generally have the biggest impact on gain, and I wanted to drop it by a good share, so it made sense to drop the lowest gain tube in the first hole (a 12AY tube has 45% of the gain as compared to an 12AX. A 12AT has 60%). I went with the Mullard in the second to further reduce preamp gain a hair. The YBA200 comes stock with an E-H 12AU7 as the splitter, which I left alone. The result? LOTS more headroom from the preamp, so with it, the ability to send a much bigger, yet cleaner signal to the power section. The overall result is a YBA that's louder, punchier, more 3-D in tone and yet still breaks up nicely when pushed hard -- and all that's still with the stocker 6550s. These two preamp tubes have already made a remarkable difference in helping bring this head to life. Couple of other things I noticed to get the most juice from this head... -Mid control: On the tip of a fellow lister, pushing the mids on this head is key. It's not a terribly mid-y head to begin with, and backing them off just seems to kill. -Scoop: Same deal... shut it off. IMO, Traynor would be doing more of a service by eliminating this altogether. -Range: Another Traynor hang-up. It's there for two reasons... 1) Nostalgic purposes, and 2) to kill tone. Set it to zero. So, there ya have 'er thus far. Still only $600 into this thing between the cost of the head and a few preamp tubes to play around with, and it's now becoming a great amp. One other note about preamp tubes -- My bass, though passive, sends a pretty hot signal. Those of you with basses putting out smaller signals might prefer another 12AT7 in V1, instead of the 'AY7. As for this and everything else in this post, YMMV. I'll be sure to report back after I have the 88s in there.