A lot of us have proc amps of some sort (I personally have an Elite Video BVP-4). Being a novice at AV stuff, I was wondering, what are the ramifications of messing with a video signal too much (i.e. taking it out of spec)?

Things like black level particularly interest me...I understand that older TVs and such used to be much pickier with what they processed, but now...is it as important to stay in spec?

I think the signal quality gets overlooked quite often by people, such as myself, who are excited to have a little creative power.