I connected the output from the M1 via the ADP 1.2 to a small 12vdc mixer that allowed me to have 4 inputs to my PA speaker system in the house. It was helpful as it also allowed me to balance the inputs and get even volume levels from all devices. This included a Radio Shack weather radio that also required an ADP 1.2 to convert to line level.
I avoided the speaker direct approach and just added a PA system speaker instead into a location where I had originally planned on having the speaker.
This has been working now for about 4 years this way.