Lamm LL2 Deluxe....

If David Karmeli weighs in, perhaps he could help. Maybe Vlad could add the attenuation switch. Worth finding out. Not sure what sonic differences exist between the 2 and 2.1
I've owned various Lamm gear over the years and have been very happy with it. Service and support has been great too, despite the fact that it is essentially a one man show (though Vlad's wife is terrific in coordinating things). 

Stereophile has an in depth review of this component and based on their review, and having it paired with an amplifier with a "normal" input impedance, e.g., higher than 20K ohms, I personally would not hesitate to own this  LL2 for $2500. A comparable quality tube preamp in the used market would demand a higher price.

Yes, most seem to agree that it's a very good pre, and well balanced overall.

Is it the deluxe version?