Many reviewer's and manufacturer's reference amplifier. Fame proceeds this unit. Original chassis that has been updated to new (4 months) circuits that are even better than the original. Power is increased by 25% into all loads with larger transformer and twice the current drive of the previous model. Just the retail on the upgrade is $7,500. Now surplus to my new system. Look at Net and reviews for additional information. With its own flight case - or course. Please note my 100% rating for over a decade.