Inna,
I don't believe the Studer will sound better then the Otari. What you will notice with regard to difference is how the Studer performs its functions. It's like a Swiss watch. Tape handling is smoother, the machine runs quite. Stopping and starting are more positive and assuring. The 810 is a world class machine. I wish I had one. I wish my ReVox ran like one! But that is the huge difference between ReVox and Studer. ReVox is a home machine, and not nearly as smooth as a Studer.
The Studer also boasts world class electronics.
Norman