software

I bought a Yamaha aes620 which came with a yamaha alnico II in the neck and a USA SD JB in the bridge.. why they didn't go with dual duncans I don't know.. anyways I replaced the crappy yamaha pickup with a covered 59 and it sounded smooth, mellow and perfect for clean tones... I put a seymour duncan pickup cover on the JB for aesthetic reasons and I think it altered the tone.. it now sounds more mellow and it seems to be stifling treble and mid response.. the only other mod I made was switching the master tone to a push/pull coil tap.. did I mess up or do pickup covers really change the tone noticeably?

Covers do change the tone a BIT - they take away some of the quot;attackquot;. With modern pickups and cover materials, though, it shouldn't be a massive difference.

Depends on the cover. Metal covers have been said to change the tone. Plastic ones - I highly doubt it. But what CAN happen is, the extra 1/16quot; (or whatever) of material in the cover makes you adjust the pickup itself that much further from the strings. THAT can affect your tone!

this website was posted on this site a few days ago, witch has custom mades guitars on it, the pickup covers are made from wood. i think that aswell as the asthetics, the wood would also increase sustain some what aswell as giving it more warmth.
check it out (some very nice guitars on here
from : localhost/www.thornguitars.com/

This was the original reason way back when that rockers started pulling the covers off their pickups -- gives you just a little bit more bite and articulation.