Has anyone heard the speaker in the Marantz 620? I am a songwriter and want to retire my Sony cassette recorder (YUK!). I need a little sketchpad recorder for when I'm away from my studio and am writing with guitar in hand. So many of these small dig. recorders only have headphone out and no speaker built in. Don't want to have to carry headphones so the 620 looks interesting. I'm not expecting any real fidelity but for those who have heard it, is the speaker about as good a quality as my Mac G4 14" iBook? Or is it even worse or better or whatever. Thanks.