Spud got it covered well but I like to add something about active pups like the EMGs on mine. I have the 81 in the bridge and the 60 in the neck of my lp copy. I put the batteries (I'm using two 9v batts) in the control cavity.
After I installed them in my guitar the first thing I noticed was that they're awfully quiet. Yep, no hum. It was recommended that I disconnect the ground wire from the bridge and tape it off. That means the strings are not grounded (and everything the strings touches) so that's a safety factor there.
How do they sound? Terrific! You can hear each note even if you're playing heavy distortions and power chords. Very good clarity and definitions and my guitar don't really sound any different than a good guitar with a set of 58s. Sounds real good clean so ignore the folks who say they're only good for metal.
The only thing I noticed was that the active pups loses a little nuances and dynamics you get from the passives but I don't seem to miss 'em.
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GUITARS - Carvin DC127M - Carvin Bolt kit
AMPS - Bogner Alchemist 112 - Blackheart Handsome Devil half stack
FXs - Roger Linn Adrenalinn III - Boss GT-10
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