Naim Niat 5i and Roksan Kandy K2 for home demo

Never had a problem with them humming. Have you tried it directly plugged into the wall without the mains block?

I had a 5i at home for 3 or 4 days in the middle of last year. Didn't notice any humming at all.

I've had one for almost two years.

There is no hum.

It is a common 'myth' that Naim amps hum and that it is somehow 'normal'. Yours will be humming because there is a fault.

I simply would not tolerate any amp (or any other component) that hums.

Get it back to the dealer and ask for one that doesn't. If he still maintains that it's normal for Naim amps to hum, then I suggest you contact Naim themselves (from the contact details on their website) and ask them. Mention who your dealer is.

Hopefully they will require him to return his demo/loan unit and ask him to stop telling customers that it's normal.

[You mentioned the two amps being side-by-side in the rack. Have you tried to see what happens with the other amp unplugged and moved away from the rack?]

Firstly, the retailer in question did not say that it was 'normal' for Naim amps to hum, just that some people believed they have a greater tendency to hum than other amps.  I have since read other comments to this effect on other forums.  I have no loyalty or preference for either brand as I have never been an owner of either brand and this is my first experience of them.  I agree that my own experience does not mean that there is a problem with the amp per se, but another's experience of a Naim amp that does not hum does not mean that there is not a problem.  

After some experimenting here is what I have found.  The source is a Squeezebox Touch (modified by Fidelity Audio) through a Keces DA-151 DAC.  I am using a extension block and power leads by Clearer Audio, QED Silver Anniversary speaker cable and Tannoy Sensys speakers.  With this setup the 5i hums and the K2 does not.  I tried plugging the 5i directly into the wall socket rather than the extension block and it still hums.  I tried different connector cables and it still hums.

Finally I tried changing the source to an old Sony CD player connected directly to the 5i and the hum disappeared (or at least was greatly reduced).  Connect it again to the Squeezebox/DAC and the hum returns.  This would lead me to believe that a) the 5i is not a faulty unit as it would most likely hum whatever the source if it were, b) the combination of Squeezebox/DAC and 5i causes the hum, c) the Squeezebox and DAC are not faulty as they do not hum with either my existing amp or the K2 and finally d) if a, b, and c are correct, there is some innate property of the 5i that causes the hum when combined with the SB and DAC.

Question asked and answered then.

Send the Nait back, buy the Roksan and be happy.

In all the tests the other amp was switched off (not on standby).  I have just tried moving the K2 amp away completely and putting the 5i in it's place.  Still the hum is there.  I have tried moving cables, holding interconnect cables away from power cables, pluggging directly into the wall socket, using different power cables.  In my system, for whatever reason, the 5i has a constant hum.  Still sounds beautiful when it is playing mind you.

Well, that's Naim's loss and Roksan's gain.

I am a simple soul regarding cables. I use the stuff that 'came in the box' from Naim and plug everything into a 'bog standard' extension block.

I also use Naim speaker cable with Naim amp connectors.

It works for me/my equipment/my mains without humming.

Your equipment/cables/mains/DAC doesn't work without the Nait 5i humming, so it's best to send it back and buy the Roksan.

That's the advantage of an extended home demo. You might never have discovered this in the shop..

could be an earthing problem, either way the naim should not hum.

take it to the dealers and let them demo it for you, if it hums its faulty, if it does'nt then its something in your system which needs to be addressed.

Another person with a humless Nait5i.  

I don't think it's as simple as 'if it hums at the dealers it's faulty and if it doesn't there is a a fault in my system'.  If my car starts on warm mornings but not on cold mornings there is still a fault with my car.  There appears to be something in my system, be that interference with other components or 'dirty' power supply or whatever, that brings out a problem in the 5i.  Luckily (for you) it seems to be a problem only a small number of users have.  Unfortunately for me, I'm one of them.

You're absolutely right though, this is what home demos are for.  As after repeated testing I still can't say I have a preference I should just go with the K2 and be happy.  

You like your DAC and Squeezebox. You like the K2. It all works together (with your choice of cables) without any problem.

No point in jumping through hoops just to try and get everything 'right' for the Nait when you don't even own it.

If I was in the same situation, the Nait would have been boxed up within minutes* of discovering the hum, and ready to go back whence it came.

*Those minutes would have been the phone call to the dealer to establish if this was a fault or not.

DazEld:

I don't think it's as simple as 'if it hums at the dealers it's faulty and if it doesn't there is a a fault in my system'.  If my car starts on warm mornings but not on cold mornings there is still a fault with my car.  There appears to be something in my system, be that interference with other components or 'dirty' power supply or whatever, that brings out a problem in the 5i.  Luckily (for you) it seems to be a problem only a small number of users have.  Unfortunately for me, I'm one of them.

You're absolutely right though, this is what home demos are for.  As after repeated testing I still can't say I have a preference I should just go with the K2 and be happy.  

yes its that simple, if it doesnt hum at the dealers then there is a problem with another item within your system, all be it cable/source/power/earthing etc

if your cars knackered then you take it to the garage to get fixed and not leave it through various seasons to see if it will start or not, if the same happens with your equiptment you return it to the shop.

THESTIG08:

yes its that simple, if it doesnt hum at the dealers then there is a problem with another item within your system, all be it cable/source/power/earthing etc

My point was that my system may be highlighting a problem with the Nait amp in the same way that the cold weather highlights a problem with my car.  It is the car/amp that has the fault, not the weather/system.  No other amp used in the same room with the same system has ever had a problem.

FWIW, I have had a couple of Naim power amps in my time, including the current one, and they have all displayed a humming characteristic at some point.  This is due to mains noise unfortunately, and unless one is prepared to install a seperate spur from the supply to the house (which I am not) then its something you learn to live with.

It has also occured from the same socket into my previous (Cyrus 8XPd) system.  Most of the time the amp is silent, but on occasion (usually when the fridge kicks in) you can hear a hum.  Doesn't detract from the amazing sounds that my Naim pre-power make though!

Incidentally, my Cyrus PSX-R hums on occasion also.  I suppose the Roksan K2 must have a very quiet (or small??) transformer. 

Naim don't recommend third party mains cables, and supply a good quality one in the box.

I would mention to Naim themselves that this dealer might have a faulty Nait - call me sceptical, but some individuals work like this in order to swing the sale the way they want it to go. I'm not saying that is the case here, but it's one possibility. Best to be safe so others aren't tricked in the future.

Any product can hum - I've had power amps that varied in the volume level of the hum coming from them. It's down to variations in the mains during the day/evening.