Thanks for the tips guys.
Mark, I'm having the opposite issue with the 834's impedance; I think. I am experiencing a very good, but too "wet" sound. The highs, particularly lower highs sound too polite, blunted. The sound is begging for a little more openness and deliniation; experience points me in the direction of much higher cartridge loading, 47K? I am handy with a soldering iron, and am intrigued by the mods. BTW, the only tube rolling that I have done so far is replacing the front stock tube with a NOS Amperex (Holland) 12au7, with mixed results. Yes, a more refined sound, particularly in the highs, but the unit lost a bit of it's dynamic thrust. It's a little polite now; not a reasonable compromise in my book. I will keep experimenting. Let me explain what I am experiencing this way: I recently bought some Nordost Red Dawn IC's to try either between my CDP and pre, or phono stage and pre; frankly, I hated them. Very detailed, not really harsh, but WAY too lean. Not so surprisingly, they work reasonably well between the EAR and pre. Tightened things up quite a bit. Still not quite right, but closer to correct tonal balance.
Happy Holidays.