Many once-common instruments are now rare or obsolete. For example, some transposing instruments have fewer variants than they used to – the B♭ soprano clarinet has largely supplanted the A and C clarinets. Other instruments, like the grand piano, overshadow earlier members of their family like the fortepiano, clavichord, and harpsichord. How does this affect contemporary performance?

Specifically, do older works fall out of favor because of archaic instrumentation? Do performers adapt and arrange the works to suit contemporary instruments? Do older works keep archaic instruments in use, among professionals at least? I suspect that the answer is that “it depends.” If so I would like to know the major historical trends and broad classes are among professional musicians. What disappears, what sticks around, and what adapts?