With the popularity of 7 string and larger guitars nowadays you need pickups that can accomidate these guitars and get a good tone for the users. Because of the extended frequency ranges of these guitars you need pickups with lots of clarity and decent output. I have found that active pickups are the best when dealing with extended range guitars. EMG was the first active pickup company to start making pickups for 7 and 8 string guitars and they are still the best out there. The biggest problem with EMG's 7 string pickups is that they are in bass pickup cases and do not easily retrofit into most guitars. The majority of guitars you see with these pickups came with them from the factory. I think this was a mistake on EMG's part, but when they first started making these I do not think there was that many 7 string guitars out to set a standard pickup size for 7 strings. Now that there is a standard size these pickups do not fall into it. To put these pickups in a guitar that didnt come with them as standard will require extra cutting into your guitar. This problem also saves EMG
a bit of money because they also work for 8 string guitars as well. The EMG 707 is like an slightly tweaked 85 for the 7 string. The 85 is an ideal choice for a 7 string guitar because it naturally has a thicker sound than the 81 and it more naturally plays up the low end frequencies of the guitar. If you are playing 7 or 8 string guitar you are not looking for a thin sound so naturally you want to retain the thick sound but also want to have some clarity with it. The 81-7 has plenty of clarity but it doesnt carry the low end that the 707 carries. They could have called this pickup the 85-7. If you are a fan of the 85 and are now playing 7 string this is naturally the pickup you will want.