Thanks for all the great ideas! The last post about a cable to hot swap batteries is neat.
First, I will contact Ted about the dual-input battery cable and custom xlr cables to connect the MM to 661. And I will buy one Naztech battery to get started.
Later on, I will try to get Digigal to make a cable so I can use the AES output, and buy a second battery.
I noticed at Xmas jam that my 661 over heated (had been running for over 6 hrs) and shut down temperately (I removed AA batteries and let it cool for 10 min then put fresh batteries in). I was unhappy yet I love pushing the limits of gear. This new rig should be able to power through even those marathon recording events.
I don't record festival often yet having a rig that I can hot swap batteries and hook up two data storage devices to allow for uninterrupted taping should be fun.
Thank you taping community for the support.