I can tell you the difference between precision and jazz. I know because I don't really like the sound of jazz basses. Again this goes back to my interest in cleaner sound.
I started playing with the sound a little I have the knob rolled just slightly forward more precision less jazz sound the bass rolled slightly forward and treble rolled slightly back and volume rolled slightly back. I use to have everything in the middle but like it better the way it is now.
I don't like full precision on my bass not sure if I don't like the pickup or just don't like full precision period. On my old ibanez I use to have it precision only 'cause I didn't like the jazz pickup at all.
as for low, mids and highs I am sort of getting it but probably will take more experimentation.
Bright being the ones with the hot pickups and dark the ones with the cold pickups I assume. I was listening to different pickups on youtube trying to find the right ones for my next bass build. unfortunately there isn't a review of every pickup on youtube and pretty much just have to go with a brand I don't know if that is wise but I pretty much settled on a set of 6 string seymour duncan basslines for my 4 string build.
Bright doesn't necessarily mean hot. Hot just means higher output.
If you listen to a recording done with a bass with round wound strings and then one with flats, that's generally the best way to hear the difference. The rounds will be brighter.
I have got to check out hart road pizza, I think that's the second time it's been mentioned in this thread.
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