[LAU] Audacity to SoX?

[mrmoo at nc.rr.com]

I realize this isn't strictly a *Linux* audio question, but my question is actually platform-independent.  I've recently realized that if I want to keep doing my vinyl to AIFF project on my new MacBook Air (running Yosemite), that Audacity doesn't officially support Yosemite.
Does anyone else use both?  Or (for whatever reason) has anyone else had reason to have to migrate from Audacity to SoX?
(I admit one issue I have yet to even explore before installing SoX, is whether I can even use the headphone jack for analog input, or will I have to get an analog to USB converter?)

Thanks in advance, if anyone has thoughts.
-Mark (longtime absentee, now lurker)