+ 1...especially the Stillpoints ESS rack! Marten with EAR and Vitus are both pretty classic combo's. I found however my previous Coltrane Alto's liked more power and were very happy with a combination of Boulder solid state amplification and a tubed line stage (Ayon). With this combo I had power, speed, tube warmth/sweetness and excellent control with deep bass.

I've heard the Bird 2's in a treated room in a couple of different setups. On each occasion I was never really satisfied with the bass. They do have a lovely timber finish though The S5's otoh are clearly better than the Coltrane Alto's & Bird 2's overall, especially in the bass.