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HELP I think I have an electrical issue??

A few months ago I had 2 20amp dedicated lines with hospital grade duplex's installed. All was well with my Bel Canto Ref1000 mono's. Well a few days ago I just got a pair of Genesis m60 tube amps. I was noticing a clicking noise coming through my speakers. I first noticed this when I was just warming up the amps with no source on. Then I also noticed the clicking when a source was on with music playing.

So it turns out that the clicking noise is my electric ignition of my gas furnace, is somehow playing through my speakers (Or maybe its just one of them, not exactly sure yet) This is a very strange and annoying. If anyone has any ideas please let me know!

Tim
tmesselt
sns
3,003 posts
 
Strange that you didn't hear this with the prior amps.

I had exactly the same furnace ignition 'click' with my dedicated circuits. It is the grounds which are contaminated, they feed household garbage through the ground.

The only cure that I know of is dedicated ground for the dedicated circuit. Be aware this can be dangerous in lightning storms as ground potential differs between whole house ground and dedicated ground. Maybe lifting ground on amps will solve as well.
jea48
4,311 posts
 
Except for I used Analysis Plus balanced interconnects before. Now that I am using the Genesis m60s which are unbalanced I am using a cheap pair NXG rca cables.

Are the NXG rca cables shielded? Try another pair of ics that are shielded.

Like I said before all has been fine with my previous amps since I installed the 2 dedicated lines 4-5 months ago, and this just started yesterday when I hooked up these amps.

Could be these amps are more sensitive to RF interference than the other amps.

The ignition spark on the furnace is high voltage and generates airborne RFI. It is also possible the HV spark ignitor is sending RFI back through the equipment grounding conductor of the branch circuit that feeds the furnace. When was the last time you had your furnace checked out? You might call someone out and have it serviced and have them check the ignition controller and the ignitor for a possible loose or corroded ground connection.
tmesselt OP
56 posts
 
Jea48,

Well I have no idea about my particular nxg cables, I cant find any info about these exact ones and they are prob about 5-6 years old so no telling. I see there are some new ones that are shielded that are prob the newer models of the ones I am using.
As far as the furnace goes, it is 5-6 months old, I just had it put it.

I also tried to lift the ground on both of the amps, this did not work either. I guess the thing I will do next is just wait for my new interconnects which will be here soon and I will see if that fixes the problem, (hopefully soon).
commcat
79 posts
 
Generally, dedicated lines are installed with a separate breaker-box specifically for those lines(separate from the main panel). A separate ground is also required. Otherwise, the electrical sound of every appliance in the house can, and possibly will, travel through your audio system.
sns
3,003 posts
 
Cables are not going to fix this issue, picking up RFI from the furnace is the longest of long shots, and they didn't do it with the other amp, should tell you something. Ground potential is somehow different with new amps, I don't know why.

I can just about guarantee you, lift the ground on dedicated circuits at AC receptacle, noise will stop and your system will take a nice leap forward. Also be aware this is dangerous, only a temporary means to determine the ground is indeed the problem.
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