Many karaoke songs got the music on one channel and music + voice on the other channel, and this would be a way to create files with only music on both channels and also to create files with music + voice on both channels. You can get rid of a channel of a stereo file by the program. BATCH CONVERSION The best midi2mp3 freeware fund you could try here miditomp3
Download MIDI to MP3 Converter Step 1. Download and install MIDI Converter Studio.