prefix question - very curious

Posted by: howard karbel on 12 June 2002

To those of you who own a CDX or a CDS,have a Naim preamp and also using a turntable with prefix, I am curious if you have experimented at all with the ground wire from the prefix being attached to the grounding screw on the preamp OR NOT attached to the preamp. If you have, what has been your experience. Which do you like better.

Posted on: 12 June 2002 by Jens

Howard,

I've tried both and didn't find a difference in terms of CD replay. At first I left the ground cable off, but as a result there was ca 5 seconds of hum everytime you switched the LP12 on. This was eliminated by grounding the LP12 to the preamp. I guess that while the Prefix itself is grounded through the DINs a la other Naim gear, the turntable itself can also benefit from grounding.

Cheers, Jens

Posted on: 13 June 2002 by Laurie Saunders

I prefer the sound with the grounding lead connected..it seems more "solid". However in my system, connecting the grounding lead INCREASED the RFI. However, by winding the grounding lead several (6 or more) times through a ferrite ring, I eliminated RFI completely......so this is the option, of the three that I prefer, and use...best sound and no RFI.
Hope this helps.
(PS...I use a Hicap for my prefix, this may affect the outcome of the above options)

Cheers

Laurie S

Posted on: 13 June 2002 by howard karbel

I guess this is not such a hot topic so I thank you both for your replies. I have not decided which way I like better yet. Fortunately, I do not have the hum problem without the lead connected and the RFI is about the same either way. I think overall it is probably better to have the turntable grounded so I will probably end up with the lead connected but was curious what others had experienced.