MungoMunro

I wonder if I could trouble you for a bit of advice? I’ve got a Line 6 XD-V30 wireless mic, which I wouldn’t mind taking out busking with me. Though the mic is wireless, the receiver needs a power supply 9v – 200ma. Could I get 4x 9v batteries, wire 2 pairs in series, making them collectivly 18v, then join them together in parallel, bringing the voltage back to 9v. Is my logic correct here, can I damage the receiver and how does this effect the 200ma side of things? Cheers!