MCACC has served me well over the years, but my next receiver will have Audyssey as I want to give that a whirl. MCACC is a "single sweet spot" type of tool similar to Audyssey, but I want multi-point calibration next time. Of course, it will cost me about 2.5x this receiver's price to get it.
Did some digging, found some info that someone else posted elsewhere (Read: These are someone else's comments from another site)
Audyssey - Easy;more of a one shot deal;cannot make certain adjustments afterwards because it adversely affects the filters
MCACC - Initial setup is easy; certain models only take one listening point, as opposed to audysseys 3, 6, or more; once you take your readings, it's highly customizable interface allows for all kinds of tweaking, but you need to read up on it.
YPAO - Simplest of the bunch, I dont know if it applies filters, but it does the chirp thing to set speaker levels and such; was generally commented as the worst of the bunch
To read more, go here: Audyssey Vs. MCACC
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