Δαφνη Ευτυχια Αρθουρος

I've noticed that when I watch a band on television, there are nearly always instruments I can see but not hear. For example, they may show a keyboardist's busy fingers and all I'll hear are drums and guitars. Or I'll clearly hear what one guitar is doing but not a note of what I can see the other guitarist's fingers playing (in which case, if there are keyboards, that'll be the day I hear those instead).

So I've been wondering: is it me, or is it them? Is it the way the bands are being mixed (this is mostly Late Night, The Tonight Show, and The Late Show, BTW, but I think I've noticed the same phenomenon elsewhere), or something about compression for broadcast? Or am I listening at a lower volume than the engineers expect me to, is the little speaker on my television not up to the task, or am I having an odd problem with my ears? Sometimes it seems as though I'm only hearing half the band.

The first clue to gather is: are other people noticing this as well, or is it just me?