nSUb and 252 grounding

Posted by: djs1784 on 12 August 2015

 

1)Is it as simple as connecting green electrical copper wire between the two ground terminals and switching to external?

2)If yes,  what will be the earthing switch position on the DAC?

(I have had custom run  isolated power line run to my screening room by electricians from the street utility fuse box. Testing equipment shows all polarity and ground are correct. The electrical boxes and outlets and hospital surgery room rated,  I use IsoTek syncro  to protect against DC pollution which was problem on my street. I am almost there, but cannot use the nSub without recurring hum in two channel set up. nSub works fine on AV input for the 5.1 mode. I was told both processor and the pre can be connected at the same time. Cables are from Naim and not damaged.

2) can the nSub be reset to original factory default? If yes, how?

 

Thank you for your help. 

Posted on: 13 August 2015 by Richard Dane

If you need to use the grounding post then you should ground on the pre-amp as detailed in the manual.  Switch the grounding switch to "external".

 

Yes, reset to factory defaults as follows;

 

To restore the factory defaults across all presets, press and hold the handset disp key for six seconds or switch the n-SUB off and then on while pressing the control panel mute button. 

Posted on: 13 August 2015 by djs1784

Thank you. I have all the manuals for all my Naim, both originals, and downloads, and cannot find any diagrams for connections for nSub. While the grounding posts are sort of obvious, the interconnect is less so.

On the Supercap: my NAP250 connection is output 5. Is the nSub connection output 4 or 3? 

On the  nSub: is the input "AV" assigned to the single rca input( 5.1processor)?

On The nSub which  input   "Amp" or the Input "AUX" is assigned for the Supercap nNaim two RCA -DIN connections cables, if that connection is used? Can I connect both the Processor and The Supercap and switch between the two?( Home theatre mode and HDX listening mode)

Which nSub input is assigned to  Naim Speaker wire connection choice? ( SL2 in my case)

If I use Naim speaker wire connection, is it the only connection allowed, or can I also use the nSub AV input for 5.1 processing and switch between the two?

 

 

Posted on: 13 August 2015 by Richard Dane

If connecting at pre-amp level for 2 channel then take off whichever DIN4 is left on the Supercap (if you are using a NAP150 you'll have two spare pre-outs on the Supercap).

 

AV is for the single .1 RCA input, AUX for the low level pre-out input on L&R RCAs, AMP for the high level inputs.  You can switch between any of these and each can have different preset levels and x-over frequency.

 

The manual tells all...

Posted on: 14 August 2015 by djs1784
Richard thank you. I will get the speaker cables made up by the dealer and play with the options. I truly appreciate your help as I do find some of the Naim manuals not clear. I am sure fault is with me.