Humming Naim gear versus alternatives

Posted by: joerand on 14 May 2016

This forum consistently sees topics about humming Naim amps and PSU's. "Is it normal", "should I worry", "what can I do" ...

Typical responses "Toroidal transformers", "part of the Naim sound", "dirty mains", "get a dedicated circuit" ...

Other brands use transformers that don't hum, regardless of the quality of mains delivery. 

Is the Naim sound so precious that it's worth tolerating the humming?

Posted on: 17 May 2016 by rjstaines

What puzzles me is that my 552DRPS hums the loudest, followed by my 500PS whereas my two 555DRPS's don't hum.  They are plugged into adjacent sockets on a dedicated 6mm spur.  My other stuff, Flatcap, NS01, NAT05, NAC-N 272 are all plugged into the same spur and they don't hum.

So some hum and some hum not.... what's going on here?    

Roger 

PS - to SJBABBY - how do you tell what kind of electricity you have, any ideas?

Posted on: 17 May 2016 by SNAIC in the Grass
Iconoclast posted:

I've owned a Nait 5i and an XS2. Both hummed at some point but stopped after being left unplugged overnight.

I'd be worried if something was humming after being unplugged all night.

Posted on: 17 May 2016 by Huge
SNAIC in the Grass posted:
Iconoclast posted:

I've owned a Nait 5i and an XS2. Both hummed at some point but stopped after being left unplugged overnight.

I'd be worried if something was humming after being unplugged all night.

I'd be even more worried if it hummed all night while it was unplugged!

Posted on: 17 May 2016 by Iconoclast
SNAIC in the Grass posted:
Iconoclast posted:

I've owned a Nait 5i and an XS2. Both hummed at some point but stopped after being left unplugged overnight.

I'd be worried if something was humming after being unplugged all night.

With Naim you never know.

Posted on: 17 May 2016 by TOBYJUG

The noiseless potted humongous transformer in my amp has either a numbness hum or a humless numb but I can not detect any noise or colouration.

Posted on: 17 May 2016 by joerand
TOBYJUG posted:

The noiseless potted humongous transformer in my amp has either a numbness hum or a humless numb but I can not detect any noise or colouration.

It's plain, the mains supplying your Naim arrive mainly in the desired plane.

Posted on: 18 May 2016 by audio1946

minimum noise will mainly be design/ core design  and position of unit period, naim as no magic design for transformers.   cost ???????

Posted on: 18 May 2016 by Richard Dane

Cost...

As to monetary cost - it's a lot cheaper to use a transformer that's more resistant to hum; both in actual physical cost (seems to be a correlation with purest steel windings sounding best but most prone to hum - also most expensive) and in the cost of the number of transformers that are rejected both by Nuvotem and at Naim.  

If Naim wish to save a bundle of money, they'd compromise and go with a hum-resistant tx and take the performance hit.  But as we all know Naim is no-compromise when it comes to the best performance within a particular design.