Turntable hum - help please

[Ris101]

Hi,

I hope you are all keeping well.

I've recently made a few changes to my system and have now detected a hum coming through the phono stage input at a fairly low volume.

I run a rega elex-r amp, it's such a good amp, with b&w 706s2 speakers, which I'm really happy with. In addition, I've got a project carbon turntable, which is fine and would like to change at some point. I've recently bought a set of chord c line rca cables to connect the turntable to the amp. The cables are an improvement but its introduced a hum. I think it is interfering with my bluesound node 2i. When I turn the node off it massively reduces. In addition, if I keep the node on and go back to my normal rca cable the hum also massively reduces.

Can anyone please help advise why this is happening. Is the Chord cable faulty, should the additional quality cable produce this and do I just need to further the node from the system.

I'm at a bit of a loss and would appreciate your thoughts.

Many thanks
Phil

 

[Al ears]

Hum is normally an earth issue the fact you have one with your old cables has to be addressed.
I am not familiar with your Node how close to the turntable it is or how you are connecting your turntable.
More information would be useful.
For instance is there an earth wire going from the back of your turntable to the amplifier?

 

[Ris101]

Thanks for coming back to me.

It is earthed from the turntable to the amp, it has a built in phono stage. When I remove the earth cable to see if the hum increases, it hardly makes any difference.

The node is 0.5meters away, as far as I can stretch it now.

 

[Gray]

I've recently made a few changes to my system and have now detected a hum coming through the phono stage input at a fairly low volume.
The cables are an improvement but its introduced a hum.

Any improvement must be good....if you can hear it amongst the hum

Take the Node out of the equation for a moment. With no mains to the Node:
Just by swapping original to Chord cable from TT to amp, you notice a low-level hum that was not previously there.
They may not actually be 'faulty' Phil, but you've proved that the Chord cables are more susceptible to stray electromagnetic interference (EMI) than your original cables.
It's no surprise that, when powered up, the Node boosts the hum level.
But you've said that, when compared to the Chord, your original cable reduces the Node hum - thereby confirming it's superior (if not total) immunity to EMI.
If the Node must remain powered, I would do whatever it took to get it further away from the TT and its cable.
Whatever else though, I would not be using the C line cable on the TT....where better EMI rejection is desirable (There are cables that would totally reject that Node interference - meaning that they would be generally better - at rejecting the ever-increasing EMI flying all around us).

 

[Al ears]

If your turntable came with this:-
'The included Phono RCA cable, Connect it E, is a high-quality semi-balanced interconnect cable with gold-plated RCA connectors that guarantees the perfect connection.'
It would seem changing it out was a mistake, best improvement to a turntable is to upgrade the cartridge.
The Chord cables are interconnects that are not turntable specific, you have to remember these are carrying a very weak signal unlike that between CD player and amp.
As Gray says try removing the node from the set-up completely.
How far away is the turntable from the amp?

 

[Ris101]

Hi Gray, Al ears,

Thanks for your help and advice, much appreciated.

Ive now reverted back to the original cable I was using and the hum is much better. Even more so when the node isn't connected. Re the distance between the turntable and the amp, it's very close in proximity. I think I'll need a longer cable for the node going forward.

Gray, re the sound gain with the Chord, I thought this could be heard before the hum came into the sound at a lower volume.

Anyway guys, a great help. Thank you.

 

[Al ears]

Hi Gray, Al ears,

Thanks for your help and advice, much appreciated.

Ive now reverted back to the original cable I was using and the hum is much better. Even more so when the node isn't connected. Re the distance between the turntable and the amp, it's very close in proximity. I think I'll need a longer cable for the node going forward.

Gray, re the sound gain with the Chord, I thought this could be heard before the hum came into the sound at a lower volume.

Anyway guys, a great help. Thank you.

What sort of cables do you use between Node and the amp? RCA I expect. Could the Chord cables be used?
It's a good idea to have a bit of clearance between amp and turntable which is why most turntable interconnect cables are 1.2m long.