dtoxic wrote:
I've heard that setting them to look like a sine wave gives a more harmonious result.
No, whoever told you that was very misinformed. Basically, each control on a graphic EQ alters a certain small band of frequency, and have nothing to do with generating or altering the behaviour of a waveform. Each individual control will affect the harmonics of a sound in some way, as each sound, no matter its pitch or frequency, will have harmonics in other areas of the frequency spectrum. Pulling a slider down will decrease the volume of the sounds in that frequency, but as a result, the harmonics of those sounds will be more pronounced.
For example, if you pull the 200hz slider down on your EQ, you may find that there's one or two sounds that become mostly inaudible, but you'll still hear 'traces' of them - these are your harmonics (which are commonly, at least on melodic instruments, located in frequencies that are multiples of the original frequency - i.e. a sound at 200hz will have harmonics at 400hz and 800hz).