My Headmaster hums, does yours?
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Gergor

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I was reorganizing my equipments, so I was really closed to my headmaster, and I heard hum coming out from the amp. I then put on my headphones, cranked up the volume, turning up to about one quarter of the full range, I started hearing hum coming out from the headphone. My headphones are pretty efficient and I don't normally listen this loud, but once I find out, I cannot get it off my mind. And this could be a problem if I start using a low efficiency phone.

While I was at it I performed another experiment. I played CD on input 2, and listened to input 1, I started hearing music at about the same volume setting as I started hearing hum.

My question to other headmaster owners, is this normal?
 
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Gergor

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OK, I mess with it a little bit more, and now I have a little bit more detail that I didn't realize before. I only head hum when I select the floating input. (and the Cardas RCA caps do not help because the coupling comes from inside, I guess).I listen to the input which is connected to the source (off), then it's quiet. So I guess it's not a big deal then. However, my question remains, is it normal to have hum from the amp?
 
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smokey

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FWIW/YMMV

I have had my Sugden Headmaster for a couple of months now. Using it mainly with the AT 2002s. I have never heard the slightest bit of hum or noise out of mine.

I'm not exactly sure what you mean when you talk about a "floating input" but you might try floating your ground and seeing if that helps at all.


Good luck
 
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KurtW

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I can hear no hum from mine, and it doesn't matter if there is any source connected or not.
 
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zzz

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Quote:

Originally posted by Gergor
While I was at it I performed another experiment. I played CD on input 2, and listened to input 1, I started hearing music at about the same volume setting as I started hearing hum.


that means that the selector switch (relay to be precise) only switches signal but not ground.

hum must be a grounding issue as well. does that happen only when two or more sources are connected to the amp or with one or less too?

what's a floating input on sugden?
 
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Gergor

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Quote:

Originally posted by zzz
that means that the selector switch (relay to be precise) only switches signal but not ground.

hum must be a grounding issue as well. does that happen only when two or more sources are connected to the amp or with one or less too?

what's a floating input on sugden?


Headmaster has 3 inputs. On my setup, one input is not connected (that's what I mean by floating), second input is connected directly to the CD player, third input is connected to an external DAC and then to the digital out (coax) of the same player. Do I create a ground loop somehow? I will disconnect one input and see if the hum goes away.
 
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zzz

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Quote:

Originally posted by Gergor
Headmaster has 3 inputs. On my setup, one input is not connected (that's what I mean by floating), second input is connected directly to the CD player, third input is connected to an external DAC and then to the digital out (coax) of the same player. Do I create a ground loop somehow? I will disconnect one input and see if the hum goes away.


Yeah, you have a ground loop (outlet - cd player - sugden [apparently doesn't switch the signal ground, thus tying all grounds together] - dac - outlet).
 
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Gergor

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I just tried the followings:

I disconnected input 3 (CD-DAC-AMP), so only input 2 is connected (to the CD player). input 1 still hum, input 2 quiet, input 3 quiet.

I disconnected input 2 as well, now nothing is connected to the amp. Input 1 (I1 for short) still hum, I2 and I3 quiet.

I connected CD-DAC back to I1, now all 3 inputs are quiet. But I still hear hum coming out from the box.

What is going on? I'm completely lost.
Please help.

May be I should just keep one input connected to input 1...

But hearing hum still give me uncomfortable feeling....

I wanted to A-B CD and CD/DAC, is there a way of doing it without creating a ground loop?
 
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Gergor

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I just realized even when I thought input 2 and 3 are quiet, they are not. When I turn the volume all the way up, I hear hum clearly on I2 and some on I3. It may have to do with the physical layout of the inputs, a lot more coupling on I1, less on I2, and least coupling on I3. The source of problem is hum on power supply. Do I have a defective unit? Please help.
 
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kelly

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I never heard hum on the Sugden I owned. It probably is still a ground loop problem. Try plugging the headphone into a completely different outlset (use an extension cable if necessary). If it doesn't go away, it could still be ground loop but if it does go away then you've isolated the problem. And, consequentially, isolated outlets are probably your best solution. Cheap isobars and Brick Wall units do this, among other things. Also try unplugging all of the sources then turning the volume up to full. Try switching to see if the hum still exists and if it is on multiple inputs or not.
 
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Gergor

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I just remembered that jude mentioned that hum on his system went away after he uses balanced power, may be this'd be my cure?

What's the source of hum anyway? I still wonder, do I have a defective amp? Or do I have defective electric power?
 
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First, are all the inputs plugged into the same outlet? If not, get a power strip of some kind and try that. You might want to try a "cheater plug". You can get one at Radio Shack. This type of plug converts a three-prong plug to a two-prong plug, by eliminating the ground. Your unit will still be grounded through the signal ground, but you should be able to eliminate the ground loop by doing this (if that's the problem).
 
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Gergor

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Quote:

Originally posted by kelly
I never heard hum on the Sugden I owned. It probably is still a ground loop problem. Try plugging the headphone into a completely different outlset (use an extension cable if necessary). If it doesn't go away, it could still be ground loop but if it does go away then you've isolated the problem. And, consequentially, isolated outlets are probably your best solution. Cheap isobars and Brick Wall units do this, among other things. Also try unplugging all of the sources then turning the volume up to full. Try switching to see if the hum still exists and if it is on multiple inputs or not.


I have a brickwall. I also tried without a brickwall and there's no difference. It's possible that brickwall only isolate hot but not ground. I disconnected all the sources, and hum's still there. I turned off all lights, hum's still there. I'll go buy an extension cord tomorrow and try another outlet. Please keep ideas coming. I'm fustrated and desperated.
 
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kelly

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Quote:

Originally posted by Gergor
I have a brickwall. I also tried without a brickwall and there's no difference. It's possible that brickwall only isolate hot but not ground. I disconnected all the sources, and hum's still there. I turned off all lights, hum's still there. I'll go buy an extension cord tomorrow and try another outlet. Please keep ideas coming. I'm fustrated and desperated.


Is the hum still present with all sources disconnected?
 
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Gergor

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Quote:

Originally posted by Hirsch
First, are all the inputs plugged into the same outlet? If not, get a power strip of some kind and try that. You might want to try a "cheater plug". You can get one at Radio Shack. This type of plug converts a three-prong plug to a two-prong plug, by eliminating the ground. Your unit will still be grounded through the signal ground, but you should be able to eliminate the ground loop by doing this (if that's the problem).


I have been connecting everything to the brickwall, however, taking everything else out of the brickwall does not help. I'll go to radio shack and get the cheater plug tomorrow. Thanks.

Oh my, I don't think I can sleep tonight.
 
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