I used to have an old jackson wired up with 1 humbucker and a single 1 meg volume pot. Recently I added a neck pickup and a volume control for that as well as a three way switch and decided that while I was there I'd rewire it. I wired it all up with some vintage braided wire and now the tone is completely different. A 1 meg pot should be very bright especially with no tone pot in the mix, but it sounds like I have a tone with it rolled down to about 7 constantly.

Could this be the vintage wire? I also get this sort of sound from the neck pickup. It sounds great all the same, but very very different.