2. amps-preamps
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Hum on Tube Amp - Can't find source

I have a hum (60hz) I can hear on my speakers and it happens with my tube monoblocks (either of them).  With or without interconnects, it even happens on either amp (have tried one at a time) with every circuit on the house tripped/disconnected, every other component disconnected from the wall (including the Internet/CaTV line) and no interconnects.  

One amp has it as soon as it warms up whereas the other one is intermittent.

Hum X doesn't solve it, iFi Ground defender either, AVA HumDinger on powerline  doesn't solve it either.

I have replaced the tubes and both amps were just tested at the factory.  Replaced the circuit breaker, tightened every wire on the breaker box, checked and cleaned all connections to ground rod.  Added a hum eliminator to the internet line.

Hum cycles a bit with the tube glow matching the cycles.

I'm waiting on the power company to come check the power coming to the house.

Thoughts?

ervikingo
holmz's avatar
holmz
2,328 posts
 

The sound in that video sounds like “motorboating”.

holmz you beat me to it

@jea48 Are you trolling with a lure too 😂

 

 

ervikingo OP
131 posts
 

@dpop I sent it because when I received them they had non OEM inline fuse holders and one was DOA.  I spoke with the seller and agreed that they should go to Manley for repairs/return to original configuration and any other repairs.

I paid for checkup and a couple of tubes that had the key broken.

Manley have been great.  They have followed the journey on this and offered suggestions.  The non conforming tube was brought up by them today/yesterday.

builder3
753 posts
 

I didn't read every post, just the first half of them. I'm going to say that it's the transformers themselves. I had this problem with my Luxman integrated. It was dead quiet for several years after I bought it, then developed a low hum. It is always the same, comes from the amp, not the speakers, and is independent of any controls or devices. The fix is new transformer(s), which is expensive, and not a guaranteed remedy.

dpop's avatar
dpop
292 posts
 

@builder3

ervikingo reports: "there is no mechanical hum on the amps; I have noise on speakers."

@ervikingo 

they had non OEM inline fuse holders

Curious as to how they got that way in the first place (I'm sure we'll never know)?

builder3
753 posts
 

Thanks, I should've taken the time to read everything carefully.

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