Nait 3 proximity to sockets...

Make (or buy?) a screened extension lead.

What problem are you experiencing?  Are you getting RFI breakthrough?

Faint hum on the phono sage...

Smithfire posted:

Hi peeps

As Im in the process of re fitting my racking I wondered if there is a way of shielding the Nait 3 from plugs/sockets electrical fields etc? Some have suggested sticking copper tape to the underside of the glass platter the Nait is sitting on (unfortunately there is an extension lead directly underneath this which cant be relocated) any thoughts suggestions?

Many thanks 

Clive 

If you've not got problems then just re-assemble as before. Just take care with your cable dressing (keep mains away from interconnects and speaker cables).

How have you got all your kit arranged at present ?

Both sets of speaker cable taped into butterflies, 3 inches either side of a extension lead with 4 plugs in it. 

Clive 

Thanks Clive - just interested how your equipment is arranged on your rack, just to gauge the proximity of the amp to the turntable. Is it a very faint hum that is only noticeable close to your speakers or louder ? Is the hum only on the Phono input ?

What is running from the sockets near the rack? If there are non-audio devices plugged in, best to try and run from a different socket, better still on a different circuit. Have you considered having a dedicated mains circuit installed for your audio equipment?

Thanks for the replies everyone.

Cant engineer a dedicated supply unfortunately. All my hifi components including plugs, sockets, cables etc are housed within a converted fireplace. The Rega deck is at the top, next down is a blu ray player and the Rega power supply (6 inches underneath the deck) underneath that is the cd player and then the Nait at the bottom.

Clive 

A couple of things to try then Clive.

Does the hum go if you disconnect the blu ray player from the mains (eliminate radiated fields). Is it connected to the Nait and if so try disconnecting that too (to eliminate any ground loops from AV kit) ?

When was the Nait last serviced ?

No hum from blu ray. Tried that. Nait serviced last week. 

Clive

Ok good - did it hum before the service ? (and is it only on the phono input you get the hum ?)

Sorry...the hum is from the speakers.

Smithfire posted:

Sorry...the hum is from the speakers.

And is it the same level from both speakers, louder on one channel, varies with volume ??

Have you tried a longer extension lead that you can move around and adjust the routing to see where the hum is at a minimum?

If the hum is due to magnetic interference (rather than electric) it may be much more difficult to block it.

Same on both channels...increases with volume. 

I assume you do run the cable under the RHS of the Nait.

Ok - as this seems to be a problem on the TT side only. Check the routing of the cables from the TT to the amplifier. It's also worth experimenting with grounding as IIRC the RP6 grounds via one of the cable shields rather than with a separate ground wire. You could try a length of cable between the Nait 3 ground terminal and TTPSU (lift one of the case screws) and see if the hum goes.

Hopefully Richard will add his experience as he's well versed in the Rega way of doing things.

James

Lh speaker cable under Lh of nait, Rh under Rh of nait.

I agree that the problem may be the grounding/shielding of the signal from the Rega TT, however there's also a another simple thing to try:

Try moving the power cable to the RHS of the Nait and both speaker cables to the LHS.

If that doesn't work try moving both speaker cables to the RHS.

Ill try that HUGE....thanks

Clive 

Also ensure that the signal cables from the Rega to the Nait don't go near to the RHS of the Nait, or close to any power or speaker cables.

Clive, does your RP6 have the Rega locking RCA PHonos fitted? If so, make sure the Phono sockets on the NAIT are nice and clean and then tighten the Rega plugs well so they mKe a strong contact.

keep the motor and the PSU well away from the NAIT - particularly the phono stage side. Likewise, keep signal and power cables apart and not running parallel.

Will do Richard....thanks

Clive 

Ah yes good point, I recently set-up a TT for someone and didn't push one of the phonos hard enough - one channel hummed like a demented beehive!

Clive, Is this related to fitting of MC boards? I know you were keen on them.

Chris