EMG is well known in the worl of active pickups but they were not always that way. They had some models that were not very successful but now they are reissuing them for the nostalgic active pickup lovers. This is an active pickup like most other EMG picksup. This means that within the pickup are a set of generally weak magnets and this weaker signal is then enhanced by the battery powered active preamp. In theory since the magnets are weaker and the amplification of the signal takes place inside the guitar this would give a quieter sound, but this did not work out on this pickup design. This is the EMG 58 not the 85 but 58. This was the original version of the 85 but it was discontinued due to the preamp being unacceptably noisy. EMG now prides themselves on having some of the quietest pickups but this pickup is nothing like the EMG's of today. Pretty much no one uses this pickup and they are pretty hard to find. They go for about 100 dollars so it costs about the same as a normal EMG its just rarer. This pickup really sounds good though apart from the noise it has. The tone kind of reminds me of an EMG 85. The pickup has a lot more low end the the traditional 81. It sound more beefy overall. It has a thicker more open sound than the 81 also. Unlike the 85 this is pretty much a bridge only pickup. It has a nice crunch to it. EMG says it was supposed to sound like a beefed up P-90 and I guess it kind of does. The P-90 is my favorite single coil design so hearing it active form is kind of weird for me. If you are a diehard EMG fan and want the true classic EMG sound this pickup was reissued for you. If you are just looking for a beefy EMG model the 85 is a great more refined version of this pickup.