Supertube Question

I recently took the plunge and bought 6H30P-DR "Supertubes" for my ARC LS26...I couldn't be happier. I'm not good with audiophile superlatives, but in Spinal Tap lingo, it now "goes to 11".

The improvements are so exciting that now I'm wondering what improvements might be gained from using Supertubes in my ARC VT 100iii...which has 2 6H30 tubes per channel, used as "drivers", whatever that is. I'd appreciate hearing from anyone who understands amp architecture and could explain whether tubes used as "drivers" would likely benefit from the upgrade as much as the preamp.

Thanks for all your observations, and Merry Christmas to all...
Can't speak to the amp improvemnets but I want to add that I have added the BAT supertubes to my LS26 and have found it well worth the investment. I can only deduce that if we both found a marked inprovement in pre-amp performance that
you would realize a similar improvemnet in the amp. I would assume that the bass will tighten and the soundfeild will increase. I guess I would just do it. If you don't notice anything then you have two extras for the LS26.
And as a final note A Merry Christmas season to you.
Can you simply swap out 6922-variety tubes for the 6H30's or did you need to have the circuit modified to do that?
6H30's can't be swapped in & out for 6DJ8 and equiv. And vice versa. Different voltages and pinouts.

The driver tube in an amplifier, IMHO, would not benefit from a "DR" upgrade. I really don't think you'd hear a difference, but I've never tried?

Theo, you're welcome for the advice to upgrade to the "DR" tube :-) Told you so...
I've also replaced the original 6H30 Sovtech tubes in my LS26 with the 6H30-DR. Like every tuning move, the result depends on the other components and I'm not sure that move would please to everybody. If there is some "slack" in the bass of your system, the DR will help with its more compact overall sound, but if your amp is very tight already (my Classé IS tight), you could find it's like too much of a good thing.

The DR also features a stunning contrast between tones of instruments and a better focus. I feel the extreme high frequency area is affected: too tight once again.