I woudn’t worry about hum. All my 500 PS’s have varying degrees of hum - it’s normal for hand crafted transformers made with Naim love. Enjoy your music pal.
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I think people make too many allowances just because it’s Naim.
At their price level there should be a consistent quality level.
I know this maybe due to individual electricity supply but there is no way that hum should be tolerated. If the product can not cope with the conditions return it for a replacement, refund or sound advice on overcoming any supply problem.
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… hand crafted, with love, & everyone has a group hug when a new one is made I suppose … oh well.
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If only life was full of people who loved each other as much as that… 
My metaphor was that there is alot to be said for hand made products in 2019 - with every British company oursourcing or cheaping us out in one way or another.
I very much doubt they’re wound by hand though, you’d be there a long time!
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Perhaps a thread for the Hi-Fi Corner?
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Any advice on removing a very faint sound of a local FM radio broadcast coming through my speakers? Note: I live on top of a large hill in a city with large hills, and I can’t move. 
When I play music it’s inaudible I just know it’s there. (Annoyance I have to live with I suppose)
You might try experimenting with some ferrite RFI/EMI suppressors. You can a get a box of the type that clip on cables from Amazon. They cost very little so it might be something to try.
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That’s called RFI. Best thing is to try a high quality mains filter.
Thanks I’ll try them out. I’ll search Amazon tonight when I’m home.
Search for “Cedmon 20 Pieces Clip-on Ferrite Ring Core RFI EMI Noise Suppressor Cable Clip.” Forum rules prevent me from posting the link, but I’m in the U.S. and use that Amazon site.
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Thanks! This could be the least expensive purchase/upgrade I’ve ever made.
No guarantee it will work, but for probably less than a decent pint it won’t hurt to try.
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The transformer hum is from the 50Hz AC mains supply, the noise is the winding & laminated core reacting (moving) & giving off a 100Hz noise
Ferrite will do nothing for a 50Hz hum as the lowest frequency ferrite ‘mix’ is only effective in the 150KHz – 10MHz range.
The general purpose types from Amazon et al will he something in the 50MHz - 500MHz
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At this point, the conversation had moved on to radio breakthrough from a local station, audible through the speakers, so I don’t think we are still talking about transformer hum.
Doh !!! must keep up, maybe stop reading the forum on the phone without specs will help.
Whatever if it is RF breakthrough, I’m wondering where it’s ‘getting in’
It will most likely be via a source component, So where to clip on the ferrites. First thing to try is get the RF breakthrough ‘on’ & then start unplugging things.
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Yes, RFI is trial and error. I get it intermittently at night sometimes, but just on phono and not when using the NDX2. I have a handful of ferrite cores to try, probably first on my TT phono cable where it connects to the phonostage.
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I’ve had the same, I got a very powerful TX from Russia, some nights nothing, some nights only when phono was live but not playing.
I used a ferrite on each phono lead, passing it twice around/through the core & that fixed it OK.
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Thanks for the tip on using a loop. I’ll give that a try.
It’s possible I even solved it in the meantime. I changed my system recently, which resulted in box+1. This weekend I bought another Fraim level, so I have rebuild the brain side from (bottom-up): 282 - NDX2 - phonostage, to (bottom-up): phonostage - HDX2 - 282. That also results in better cable dressing with no cables touching each other or on the floor.