I would like to add this post by Wayner, a member of Audio Circle. This was apparently the cause of the OPs hum/buzz problem.
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Re: Hum whenever preamp and amp put in system...Help!
« Reply #25 on: 16 Jul 2014, 02:45 pm »
Quote:
"I have an FM tuner, that when turned on, will make my systems hum, because the transformer in the FM tuner is poorly designed/poorly shielded. I too, was fighting a hum issue, thinking it was caused by dirty AC or poor interconnects or something else related to a ground loop.
The answer was distance. Moving the FM tuner away from the amp and preamp solved the problem. The tuner's transformer was creating a larger then normal magnetic field, and that field penetrated my preamp and induced hum. This may be the cause of the hum for you. Perhaps your amplifier's transformer is affecting your preamp, or your preamp's transformer is affecting your power amp.
My suggestion is to separate the 2 much farther then you have them now, even if that means using a 2 meter (or longer) interconnect to accomplish this. I have a semi-high degree of confidence that your hum is caused by EMF."
End of quote.
OPs later response,
Re: Hum whenever preamp and amp put in system...Help!
« Reply #26 on: 16 Jul 2014, 09:38 pm »Wayner,
Quote:
"You are my hero! After several years of this quagmire, it has been solved. Moving my amp as far away from the preamp, and as far away from the outlets and electric panel has solved the issue! This has escaped 3 electricians, countless audiophiles, and tens of hours with me getting increasingly frustrated. THANK YOU!!!!!!!!!!!!!!!!! When surveying the landscape I realize that there is essentially an equilateral triangle with the 2 base corners representing my 2 electrical panels in the home and the apex represents a confluence of 3 separate circuits converging at that point. Whether or not moving the components out of that is the reason for solution, I'm thoroughly relieved. Thank you all for your help! Special thanks to Wayner of course but again also for Dave E, Tom S, Frank V A, Roger M, and everyone else that I've not had the pleasure of meeting in person or via telephone conversations. I'm indebted to you all."
David
schw06
http://www.audiocircle.com/index.php?topic=127372.20