Tomryan- The Harbeth's never really struck me as all that hard to drive with tubes (my current Usher CP 6371s seem like a tougher load). Other than Plinius 9200 and a Jungson JA88C, never tried any other solid state- maybe something like Bryston would give a different perspective.
The Granite Audio monos are excellent- I have a pair of the 861s upgraded to what they are now calling the 864 model. Nice build quality. They have a well-balanced sound- neutral in a good way. Fast, very detailed, good bass, and touch of midrange warmth, but still tansparent. They work well driven direct by a source, but I recently added a Dehavilland Ultra preamp, which has made a definite positive improvement.
The Granite Audio monos are excellent- I have a pair of the 861s upgraded to what they are now calling the 864 model. Nice build quality. They have a well-balanced sound- neutral in a good way. Fast, very detailed, good bass, and touch of midrange warmth, but still tansparent. They work well driven direct by a source, but I recently added a Dehavilland Ultra preamp, which has made a definite positive improvement.