I had a stereo that allowed me to plug in a mic and it turned down the vocals of the song while still playing the music from the song at the same volume. I could also adjust the volume of the mic. It broke recently and I was wondering if you can do that with any other types of mics / stereos. I don't want to buy a karaoke machine because I want to use the music I have and not special karaoke cd's. I don't care about seeing the lyrics. Can I do this with any microphone or not?