Jon, my concern still stands. What exactly are you changing from the original Arx formula? Regardless of the outcome, as I have an A5 as a reference I can guess the end result of any changes you are making. Also when I bought the A5 I remember being told not to wait for this new version as the changes will be minor (just more headroom on the highs). Is it still the case? This is important for me as I need to match the A7 with the old A5 for a 5.1 system someday.