Mac actually has many types of DSP built-in to its OS: 31-band, parametric, peakings, shelfing, various types of reverb, you name it. These are all free. However, the user needs a hosting application to access these EQ interfaces, and hosting softwares on Mac typically are not free.
Right now I am using Audirvana and Audiohijack. Audirvana can do bit-perfect and exclusive access but can't do system level hosting. Audiohijack can host system level DSP, including those EQs. The only downside is that isn't "bit-perfect" if you care about that.
I recommend Audiohijack.