tysonlt
Power User
In those days they used the just temperament system, so the instruments were only in tune for a particular key. That’s why classical pieces name the key they are intended to be played in. Modern pianos etc use equal temperament so that it sounds tuned ‘enough’ in any key. I’ve always tuned my B and E strings slightly sharp because I dislike choosing whether to have the G chord or the A chord perfectly tuned.I wonder how musicians got through the 'Mozart' era with no visual aid.