I have revised the 88BM setup guide to include the requirement to conduct a time alignment between the two 88BM's. My thanks to
for pointing out the requirement for a time alignment, and to
for the example that made it all clearer to me.
I have done some testing, observing the behavior of running Audyssey to determine speaker distances, a key part of the time alignment. Several observations, none of which are new, but bear repeating:
- Dirac trims and delays remain active whether the Dirac filters are on or off.
- Dirac filters are non-zero for configuration slots with an actual saved Dirac calibration. If a configuration slot is empty, the Dirac trims and delays are zero (as expected).
- The 88BM hardware introduces an 18.5ms delay, equivalent to 20.8 ft. So when you run Audyssey with the 88BM in the signal path, a speaker 10ft from the MLP will register as ~31ft in the AVR.
One uncertainty that I still have is whether the time-alignment using Audyssey should be run after
the Dirac Live calibration, or before
. In my write-up, I recommended after. If this is not correct, please let me know, and explain why.
The revised guide section starts on page 8, and the guide is linked in my sig. Feedback appreciated.