The SCIIa (SC2a) is essentially an SM-1 with more options on finish.
The model designation change came to avoid confusion between the SC1 and SM1.
Since the SM1 uses the same drivers as the SC2 it was the logical progression to call it SC2a.
The model designation change came to avoid confusion between the SC1 and SM1.
Since the SM1 uses the same drivers as the SC2 it was the logical progression to call it SC2a.