Hey guys,

I'm new to UG forums and I just wanted your opinion on something regarding my guitar.

I have a Cort EVL-K47B 27" scale 7 string whose pickups I just replaced with a Seymour Duncan Nazgul in the bridge and Sentient in the neck. It's currently on a 9 gauge setup and tuned standard half step down with the 7th string tuned to Ab. (Ab Eb Ab...)

There's this really weird metallic ringing noise I get when I play the 15th fret of the low B string and the E string (7th & 6th string.) which is significantly more pronounced when I use high gain settings and even more so on the neck pickup.

The 7th string when played open has this really annoying twangy noise which has less sustain and starts wavering towards the end. Also when I play chords, I can barely hear the 7th string and it seems overpowered by the other strings.

The action is quite high on the bridge side and there doesn't seem to be any buzz elsewhere (except a livable buzz on the high b when played open and a few higher frets).

Initially the neck pickup was installed upside down and correcting it hasn't solved the problem. My idiot of a guitar tech had also installed the bridge upside down and reversing it hasn't really changed anything. The problem still persists.

I also have a loose connection problem with the pickup switch in the bridge position. The guitar tech says that the pickups are wired properly according the the Seymour Duncan wiring diagrams.

There are virtually no guitar techs where I live who can be trusted with my guitar due to numerous bad experiences.

Can anyone help me figure out what's up? I can put up pictures/recordings if you like.

Any help would be much appreciated.
Strange ringing/metallic noises on an electric guitar can be caused by a lot of things: a high fret, a loose bridge saddle, or a poorly fitted nut. Diagnosing the problem is a process of elimination: check each component and see if it is loose, warped, chipped, etc. If it is not, then move on to the next.

The loss of sustain and the annoying noise on your 7th string are probably caused by either a bad bridge saddle or a badly cut nut slot. Sadly, these are common problems on guitars being made these days; including a few expensive guitars. Give your guitar a thorough inspection; looking for these problems. Believe it or not; a magnifying glass can really help with this sort of inspection - especially when looking for a slightly loose or high fret. In some cases, such noises can be caused by an out-of-whack truss rod; requiring a quarter or half turn to fix. This is not usually the case, but keep it in mind anyway. Based on what you describe, I do not believe that the problem has anything to do with your electrics/electronics. It definitely sounds like a hardware problem.
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