Can the Sennheiser HD650 do BIG SCALE classical???

You might look for a solid state amp at headroom or something like that, but I think it is the Senns. Those headphones are neutral and decent, but not very dynamic or frankly exciting. They caused me to go to Grado headphones where it's all musical if not romantic and agressive (but don't sounstage like the Senns), then I found the most dynamic and musical in teh K1K's ;)

Rob - Frankly I'm not that into Grados for comfort alone, they are just disqualified as I don't find them comfortable.

I am looking into the K1Ks however. They look interesting. Given that I'd be willing to spend a grand or so on an amp for the senns, it probably makes sense to also consider the K1K along with a nice, cheap tube amp (norh?) for pretty much the same amount of dough.

That's true Goatwuss. I would rule out Grado simply for the lack of soundstage as well. By no means was I recommending them over the Senns for symphony recordings. You can use the amp you have now if you are willing to swap out the connections on your amplifier for your speakers assuming you have one, get an adapter, or as you mentioned buy a relatively innexpensive low powered amp 7watts or more is enough.

Goatboy- As you may remember, I've got the K1Ks here is you want to try those as well. I think you will be spoiled, but I will also say that since they are very resolving, I would not recommend goind with a "relatively inexpensive low powered amp" 7 watts is more than enough, but they should be good watts and a good source. My experience has been that very resolving transducers in your system (be they cartridge, speaker, DAC) will really bring out all the crap that is upstream.

Swamp - I read your post again and now see that mention of the K1K - I must have missed it... heh interesting

So You wouldn't recommend a relatively inexpensive low power amp? Maybe something like a Lamm ML2? Audio Note Ongaku?

Ha! I think starting with a relatively modest low powered EL34 or other amp would be ok. The problems at least wouldn't be brightness/harshness/dryness. Granted, the whole point of the pursuit is for macro-dynamic control, so I wouldn't want to be throwing that off the boat... but if relative to the Senn650 the K1K with a modest amp is in another league (sorry about the A-phile cliche), then I would be quite happy. I'm sure there are plenty of sub $1000 amps that wouldn't butcher the job too badly. I'd either be using my supratek or my EE Minimax as a pre, and both of those are quite transparent and good sounding, so all I'd need is the power-amp section. I'd be interested to hear what they'd sound like with my plinius 102 in class A... Would it damage them to hook them up to serious 100WPC+ amps just for the fun of it?

Anyway - Your entourage of gear sounds very compelling for a potential drop-by. Do you have the merlins set up too? If so, do you have a photo of the room/setup?