Though 10mm (or 6mm) cable is generally considered an upgrade over standard mains cable, there are plenty that find high quality OFC cable of smaller and more manageable dimensions to be sonically preferable to 10mm cable. I currently have a 6mm dedicated spur but don’t know if creating a dedicated supply or the conductor dimensions had the most impact. I suspect not many will have compared a dedicated spur of regular domestic cabling against the oft touted 10mm, rather they will have installed a dedicated spur directly with a larger cable and observed the overall effect.
Installing Doepke RCCD and a Gigawatt breaker brought further improvements in my setup and I am now considering changing the in wall cable to Furutech FP-3TS762 (5mm).
I’m not so sure, i believe the dedicated bonkers big cable run obsession is so the impedance can be very very low.
Impedance is measured in Ohms, Kraftwerk kindly provided us with a song about it
Some transformers just hum where others on the same mains circuit don’t, so improving mains supply doesn’t necessarily help.
Then there’s hum induced by pollution that is generated outside your own home, perhaps by a defective appliance in a nearby building, or maybe overvoltage. Isolating the HiFi from other domestic circuits is clearly going to have no effect here.
When hum is caused by devices in your own home a dedicated mains circuit can help to isolate from it, although it is arguably better to identify the offending device and replace or repair it, as there is still no guarantee that you will achieve total isolation.
Despite all that I would always put a Naim system on dedicated mains because it seems to improve sound quality significantly.
My current Naim units ( Uniti Nova and NPX 300) are completely silence. However I had an Atom HE which had a loud transformer. I got a mains conditioner but unfortunately it did’nt help. Shame on a good unit but the noise between the tracks bothered me so much that I returned it.
Hi Stu,
There is a thread on the old Naim Forum called “Suffering from those transformer hum blues?” which charts our journey to deal with it.
We tried several expensive power conditioning devices which didn’t work.
However, an Airlink Transformers Balanced Power Supply hard wired into a dedicated radial supply for the hifi worked a treat and with no downsides that we could detect.
It benefitted the Supercap, NAP135s and 555PS as all were suffering from transformer hum. It cost about £550 at the time.
Here’s a photo of the Airlink BPS5120MP in situ, fixed on the wall below our main consumer unit:
The dedicated radial didn’t stop the transformer hum but inserting the BPS worked a treat.
I checked with Naim before installing it to ensure compatibility with Naim electronics.
I had the same problem with meter and hi-fi on opposite sides of the house. My electrician routed the 10mm2 T&E cable up from the new CU in the garage through some built in wardrobes in one of the bedrooms and up into the loft. It runs the length of the loft and then drops down the outside wall via conduit and into the lounge. He’ll find a good route for you. Good luck with the install - Very worthwhile.
Same here James!
The extended length of run made 10mm2 T&E the most appropriate option for us too in order to minimise supply impedance and ensure that those Naim power supply reservoir capacitors all filled up as fast as possible.
If you need / prefer multiple sockets then (reg’s permitting) a 6mm2 ‘ring’ circuit would facilitate that and effectively give a lower impedance link than a single 10mm2 radial circuit. Plus it better maintains the integrity of a single circuit as opposed to multiple radials. That said, a single radial and socket plus a hydra is my preference now.
Lapp Olflex Classic 110 CY 10mm sq to Furutech (G) single socket. This cable has a tinned copper braid and PVC outer sheath.
And Belden 83803 (12 AWG) cable to an MS HD Power (G) duplex socket. This cable has (7×20) tinned copper conductors, Teflon insulation, 100% Beldfoil shield with 85% tinned copper braid and a Teflon jacket.
The thin Belden cable had a circuit impedance of 0.08 Ohms and the fat Lapp cable measured 0.04 Ohms.
The Earth loop impedance of the Belden radial was 0.07 Ohms, of the Lapp cable was 0.06 Ohms, and the house ring main was O.41 Ohms.
I have not installed a dedicated circuit yet…but when I do it I will be installing 10mm mains cable and a bigger dedicated earth cable - probably 16mm. Quite how you terminate 16mm cable at a mains socket…I am not sure…
Stu, I fully understand where your coming from. I’m in Canada for comparison a standard grade outlet is maybe $2, a Cryo treated Hubbell is $50 & the Furutech NCF Rhodium is $300+. When you look at just the cost of an outlet $300 is completely ridiculous, but after installing it, I believe it is probably the best $300 I’ve ever spent in audio (I’ve spend far more in different upgrades for far less improvements in performance). I’m fairly confident that while your wallet won’t thank me, your ears most definitely will. The Furutech Discussion thread has numerous posts about this subject, so check it out if you’re looking for more info.
Edit: I’ll add, I have used Cryo treated Hubbells in the past (which are a “budget friendly” recommended upgrade here). With them installed it was, “I think I hear a difference, maybe?..” With the Furutech NCF Rhodium installed I sat for hours with my mouth open, shocked, continuously saying, “how can just an outlet make that much difference?”. And I know some will say, you probably only think you hear an improvement because of the money you just spent. I have bought a number of different things over the years (tweaks in the same price range, etc) that were non returnable & didn’t like what they did to the sound.
Well sort of. Firstly its worth restating that the issue is with using a toroidal transformer, and therefore nor just a Naim issue.
In their new kit, they address this by using a standby mode that turns off the toroidal transformer, and uses a small SMPS power supply to keep certain electronics alive and ready. So when in playing mode, the hum will still potentially be there.
