On using your ears

I've been doing repairs for a while and have noticed that some musicians like to mark "their setting" on the gear. Sometimes there's tape with the setting numbers written on it, other times there are lines drawn on the faceplate and knob that are meant to match up. This hits me as strange, since your sound is not an absolute. There are so many variables that affect your sound, to list a few

• the size of the room
• is the room full of people or empty?
• are you outdoors?
• have the speaker cones been in a humid environment and absorbed some moisture?
• is your amp coupled to the stage, sitting directly on it?
• with some speaker cabinets, where are they pointing?
• How old are your strings?
• etc, etc

To assume that you can dial in your sound in your bedroom or rehearsal space, and then transplant it somewhere else is wishful thinking. At best it can be a starting point for dialing it in, but there's still work to do. The best advice I've heard is to adjust your amp settings like you are in a dark room--in other words, don't look at the numbers on the dial. Even better, get rid of the numbered knobs and face plate markings and just twist the knobs.

I got a callback on one repair that I did saying that the amp now had more treble. What had happened was I had taken the treble knob off the amp and put it back on in a slightly rotated position. This person was locked in to the notion that their treble setting was "7" and to their credit their ears were good enough to hear the difference. They could have adjusted it it by turning the treble down to 6.5, but it wasn't right for them until I pulled the knob off, unrotated it a click and put it back on. I guess there's nothing wrong with that, it just makes me say "hmmm..."