I see a lot of advice to take it to a pro which is certainly advice I would heed. Steve wrote about an incident where two guys on stage touched guitars and sparks flew. This tells me it is important that all the gear goes back to one common point. This is particularly true of earth or ground points. Some usually older buildings may have electrical circuits going back to different earths this can create issues such as earth loops, tingling and/or sparks and also increased buzz or we would say 50 cycle hum. For you 60 cycle hum.

Just a thought

Tony


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