[Ryan Cao]

Hello!

I recently got a Manley Absolute. I love its sound, but the background hum really bothers me. Another Manley owner having the same problem suggested that changing the power cord could reduce the hum a lot.

The power cord he suggested is too pricy($900+). Any recommendation on some budget cords?

My major goal is to reduce the amp’s hum, so sq improvement is not so important (as long as it doesn’t negatively impact the sq).

Thanks a lot and happy holidays!

 

[kumar402]

Wow $900 power cord to reduce Hum
I’m no electrical engineer but I would first suggest to check the ground or use it in outlet which is not shared with any other noisy device. Next you can try some devices like Ifi AC iPurifier etc. If nothing works then get better amp then an amp that needs $900 cable

 

[technobear]

By a $20 mains filter and plug the Manley into it. If that doesn't stop it, your Manley might need a service. It shouldn't be humming. I think I would reach out to Manley for advice here.

 

[Ryan Cao]

By a $20 mains filter and plug the Manley into it. If that doesn't stop it, your Manley might need a service. It shouldn't be humming. I think I would reach out to Manley for advice here.

I am not familiar with mains filter. Is it the same thing as Ifi that kumar402 suggested?

 

[technobear]

I am not familiar with mains filter. Is it the same thing as Ifi that kumar402 suggested?

Any TV or hifi shop will be able to sell you a plug-in mains filter.

 

[manueljenkin]

Hello!

I recently got a Manley Absolute. I love its sound, but the background hum really bothers me. Another Manley owner having the same problem suggested that changing the power cord could reduce the hum a lot.

The power cord he suggested is too pricy($900+). Any recommendation on some budget cords?

My major goal is to reduce the amp’s hum, so sq improvement is not so important (as long as it doesn’t negatively impact the sq).

Thanks a lot and happy holidays!

Is the amp really any good to bother about cables, and isn't there any way to fix it other than going for expensive cables? I haven't tried power cables at all, but you might want to try something like this :

Another video of cable demos, not sure if this will be helpful to you : . People seem to be positive about vovox textura, and it did sound nice in the sound demo, so maybe you can try demoing it if you're actually going the cable fi route.

 

[teknorob23]

Decent mains cables can bring a host of benefits, but this amp should be capable of running quietly. Has it hummed since you’ve had it or has it come on? Was it after installing new tubes? Have you checked it’s earthed properly. Have you tried the amp in a different location on your house and or someone else’s. Answering these questions and more should tell you whether it’s a mains issue. If you do try an expensive cable buy it from somewhere you can return it to, because my money’s on it being something a cable won’t cure.

 

[Deolum]

Power cables never changed static noises for me. Are you sure it's output impedance fits your headphone and you have no groundloops?

 

[JDFlood]

Typically a hum is caused by having different components plugged into different outlets. One takes one path back to the fuse box, the other takes a different which offered greater resistance to the current. There is a trickle of power between the two outlets to equalize the difference. You hear the trickle through your headphones. I just wanted to make sure that isn’t it. There should be zero hum from your system. I agree, contact the manufacturer if it isn’t a power differential problem.

 

[Polygonhell]

You minimally want to determine what the issue is before splashing $900 around on a power cord.
Certainly check with the manufacturer, but it’s not that unusual for some tube amps to suffer from noise in some environments.
But that noise can be from a whole host of possible sources, ground loops as mentioned, but if you get something like a HumX and try the amp disconnected from a source, that will pretty much rule that out if it still hums.
It can also be RF related, though IME it’s usually not a hum, the little wires in the tubes act as aerials.
If it’s in one channel and not the other it’s probably a tube.
I had a ZMF pendant that had an audible hum here, went back to A&S, they claimed they couldn’t hear it, tried everything short of a power regenerator with no luck, eventually I sold it, the person who bought it has no hum, so it was clearly something to do with my environment. I have half a dozen other tube amps here and they are all silent, so I’m none the wiser as to what the issue was.

 

[Ryan Cao]

Decent mains cables can bring a host of benefits, but this amp should be capable of running quietly. Has it hummed since you’ve had it or has it come on? Was it after installing new tubes? Have you checked it’s earthed properly. Have you tried the amp in a different location on your house and or someone else’s. Answering these questions and more should tell you whether it’s a mains issue. If you do try an expensive cable buy it from somewhere you can return it to, because my money’s on it being something a cable won’t cure.

Thanks for the help!

I purchased the amp from another Headfier. It has hummed since I got it. The power socket is grounded (I purchased an iFi purifier hoping to tame the hum. The purifier indicates that the socket is grounded properly). Yea, I tried different sockets in my home, and my friend's house. It's always the same hum.

It's worth mentioning that the amp is only connected to power and headphone, because I'd like to rule out the possibility of ground loop.

I just got Pangea Audio AC 14SE from Amazon. Unfortunately, it didn't help with the hum

 

[Ryan Cao]

Typically a hum is caused by having different components plugged into different outlets. One takes one path back to the fuse box, the other takes a different which offered greater resistance to the current. There is a trickle of power between the two outlets to equalize the difference. You hear the trickle through your headphones. I just wanted to make sure that isn’t it. There should be zero hum from your system. I agree, contact the manufacturer if it isn’t a power differential problem.

I was connecting the amp only to the power and the headphone. Would this setup rule out the possibility for the issue you mentioned? Thanks!

 

[gimmeheadroom]

Why don't you contact the manufacturer?

 

[JDFlood]

Why don't you contact the manufacturer?

I was connecting the amp only to the power and the headphone. Would this setup rule out the possibility for the issue you mentioned? Thanks!

Assuming you have a streamer, DAC, and amp. The Streamer, DAC, and amp should be plugged in to the same outlet.


if that doesn’t work. Move the whole system somewhere else... does that change the humm. Spread out all the components... does that change the hum?

 

[Deolum]

I was connecting the amp only to the power and the headphone. Would this setup rule out the possibility for the issue you mentioned? Thanks!

Which headphone do you use?