I've been hearing alot of talk about fretless bases lately and I have got currious. What kind of sound do they have? Will a fretless get good growl? I'm thinking of a sixer fretless if they can growl. I haven't decided what kind I want but I know it will have a lined fretboard. When fretting a note on a fretless is it held directly above the fret line or will I just have to listen to the note and play it by ear? I hope these questions make sense, this is a whoel new world of bass to me.