I should have made myself more clear.   While I do have an acoustic/midi accordion, here I am referring to my all elecronic accordion.  A guitar wireless transmitter will do.  It is just that I can't find that stereo tranmitter that I had seen a couple of years ago.  It looked like a very professional, robust system.   I have two AKG Guitar Bugs, but I do not want to deal with rather large two receivers.   I found this 
http://www.smoothhound-innovations.com/ last year. The manufacurer did a test for me and advised against using two transmitters so cloese to each other.    I have no background in electronics and I am wondering if I can use a Smooth Hound didigtal wireless system along with an analog system by AKG for stereo.  
By the way, I am familair with all the midi/audio systems for an acoustic accordion.   I used to have a midi accordion technician who undid all the proprietary systems.   For instace, a Musictech wireless midi system can be as expensive as $2,000.   The tecnician would make a small battery pack with an midi output for $200 to $300.  Then I can use a better wireles midi system for only $200.