hello,
I know it is an old thread, but, for people still interested, I want to tell you Studer A3 was a product manufactured by a swiss company named PSI Audio. The product still exists under this name PSI AUDIO A21-M. I don't know if you could find it in the states since I live in France, but if you have access to it, you definitely should consider it : I use it for recordings since years at the Lyon opera house, and it delivers incredibly realistic sound for instruments as well as voices. The acoustics and reverb effects can be heard in details. Position of sources can be set with ease and precision, in left-right direction as well as in depth.
Bass register is rock solid, and you won't need a subwoofer in classical music. But no frequency will be proeminent in level, neither in time : The time coherence is probably the main reason of its realism ... (in opposition to Yamaha NS10, which was also considered in this thread : Its time advance for hi-mids was the reason of its success. It gave a sensation of intelligibility that was very appreciated by many mixers). Try PSI Audio ! And if you can't afford them, work with a grado headphone (I recommand SR250) !
