Emu XL-7 & MP-7 User's Group

I will attest to this much:  the power supplies on the P2K/P1K modules.  The very late ones appear to have better caps and are shielded.  There are also some component changes on the main boards--might possible be different converters.  I'm not sure how much, if any, audible difference there is.  

On a purely superficial level, some Command Stations say "Made in the USA" while some others say "Made in the China".  

I also wonder how the keyboard models (PK6 etc.) differ from the others.