Loving the MT.  More than enough power for my Ref 3A De Capos.

looking to start rolling tubes.  Anyone try the OB3?  I am more interested because of the blue glow but hoping the sound is good too  lol

My experience with the mini torii has been that rolling signal tube first then output tube has greatest effect on sound.  Once you get that combination right, fine tuning can be done through choice of regulation and rectification tubes

Funny.  Although my tube-rolling is somewhat limited, in my case the first thing I need to define is the synergy between driver and output voltage regulation tubes. Unless one tries a really difficult or atypical 6V6, I've found output tubes have less of an impact than this couple. Next, is the output tube, then the rectifier and finally the input voltage regulation tubes. Go figure!

I'll probably change my mind as I try other output tubes (tried only three so far), but this has worked for me.

Very fun!  I got some extra tubes with the MT and already tried the output VR tube going from a oa3 to a od3w.  Preferred the oa3 more pop and clarity, the oa3w seemed to muddle the sound a bit.

also swapped the stock JJ 12au with Phillips/Amperex E180CC  The Philips was a cleaner sound.

Now i have lots of 12AU's around to try.................

I have not checked to see if the trannys are hotter with the E180cc.  

i'll try it

Agreee on the 12AV7 and 6y6. Both heat up the trannies.

I wonder if there's some consensus from Mini Torii owners regarding a specific type within the 12Au7 ... 12Av7 driver family that may seem to be more favorable to the sound in the Mini.

Reason I ask, is tube-rolling the driver is pivotal in fine-tuning the amp, but it gets too complicated (too many possible options) without some threshold rule of thumb to narrow the choices down to, say, a single type.

If such rule were to exist, one would only need to try for brand and sub-types within that particular type only, whether it is 12Au7 or 12AT7 (IMHO, going to 12AX7 or 12AV7 would not be intuitive choices in the Mini given wider specs differences.)

There have been just a few reports on useful driver types for the Mini in this forum, from which it would seem as if both 12Au7 and 12At7 types could work, provided one is lucky enough to find the right synergies in a few attempts.

This is why I find it would be very useful to ID some trends, because as we all know, one tube may work wonders in somebody else's system, but not necessarily in ours. The trial-and-error is thus unavoidable.

IMHO, if one could nail a reasonably synergistic driver choice, most other tubes in the complement would most likely align themselves to this influence, at least in a small amp like the Mini, with only one driver per channel.

I've personally found huge differences between an RCA 5963 and a Brimar 12AT7, so far my only two choices.  I guess it boils down to asking those who have tried many more alternatives.