[maxmsp] [OT]software synthesizer with free scaling

Hi,

can someone recommend a software synthesizer with free scaling?

One of our teachers want to use it for education.
Years ago he could do it with Yamaha Micro Tuning option.

Or perhaps you can tell me another option.

(Yes, I know the possibility to program it in MAXMSP.
But I don't have the time to do it by myself.)

Best,

Juergen