Can your pickups be too high? i raised my bridge pickup so that it is just low enough not to get hit by the strings. Can it ruin your tone if you get it too high?
Yeah , but it all depends on your ear. It can mess with sustain and stuff.
It does depend on what kind of magnet's in them. Alnico's a weaker magnet than ceramic so they can be closer to the strings. If it's too high the strings will lose sustain due to magnetic pull, but if it's too far the pickups won't receive as much vibration. Just experiment and try to find a balance.
It will affect the sound, but shouldn't permanently "ruin" the tone or anything.
Id suggest everyone play around with their pickups heights. It makes a huuge difference in the tone and response of your instrument. You can hear it easily adjusting then playing ect ect