signal ground for superline system

Posted by: asprin on 01 August 2017

Hi all,

i've been reading with interest all the posts on here about signal grounding and I've realised that my system, being based around the Superline may have no signal ground connection to earth and therefore is 'floating' (all the naim boxes are obviously all earthed correctly though).

I'm running a Townshend Rock II turntable with Heed Orbit2 power supply into super-capped Superline with burndy, a 72, hicap and 250. power cabling for the naim boxes all using a Grahams hydra.

Since, as I understand it, the signal ground is usually at source but the heed orbit does not have an earth pin (and my only other box, a Yamaha CD player is powered through a figure of 8 socket), am I right in thinking that there is no signal ground in this system?   

If there isn't a signal ground ....... does this matter and will i notice the difference if i address this? Sound is good (now I've dealt with the RFI breakthrough by use of capacitive loading on the Superline) although I've always wanted a sound to come from a 'darker' background.  I've read here of people wiring up a plug with an earth connection only and plugging it in, linking the other end to the other sheaths of RCA contacts etc, would doing the same but connecting to the turntable earth point on the Superline and/or 72 achieve what I'm after or am i best to leave well alone?

Thanks in advance

Jim 

Posted on: 01 August 2017 by yeti42

A merlin wouldn't have geven you an earth either.

I removed the CD player from my system  a few months ago and tested continuity to earth (at one of the mounting screws on the socket plate) and got around 7Ω to either the Rock chassis with the latter connected to the superline earthing pin. Plugging a DVD5 (who's manual says it provides a signal earth) didn't make more than an Ohm's difference to the measurement. I have a 552 and couldn't hear much difference either way playing vinyl.

Posted on: 02 August 2017 by Richard Dane

It's worth experimenting and going for whatever gives you the lowest noise and best sound - trust your ears.

Posted on: 02 August 2017 by The Strat (Fender)

What Richard said.  I found best result was to connect to the earth point on the 282 - dealt with the RF problem as well.

Regards,

Lindsay

Posted on: 02 August 2017 by asprin

Thanks all, 

Lindsay, did you connect the 282 earth point directly to the mains earth or did you mean you connected the tonearm lead to the 282 rather than the Superline? 

If i did wire up a mains plug with an earth lead and connected to the earth point on the Superline would this in effect give me a signal ground? Hopefully this wouldn't introduce an increased risk of frying my beloved system (?)

 

jim

Posted on: 02 August 2017 by Richard Dane

Noooo..  don't do that. 

Posted on: 02 August 2017 by Bob the Builder

I am using a Trichord Dino Phono amp with  an LP12 282 system and can sometimes get a bit of hum I have cured it temporarily by keeping the phono amp as far as possible from the 282/250 and also keeping the phono amp as far apart from its own psu as its cable will allow.  Obviously this isn't ideal and so this thread is also interesting to me as if I can avoid the hum by eartning the tonearm and my 282 together that would be brilliant.

Posted on: 02 August 2017 by The Strat (Fender)
asprin posted:

Thanks all, 

Lindsay, did you connect the 282 earth point directly to the mains earth or did you mean you connected the tonearm lead to the 282 rather than the Superline? 

If i did wire up a mains plug with an earth lead and connected to the earth point on the Superline would this in effect give me a signal ground? Hopefully this wouldn't introduce an increased risk of frying my beloved system (?)

 

jim

The little tonearm earth lead to the 282 rather than the Superline.

Posted on: 02 August 2017 by Ravenswood10

I have my Ekos SE tone arm earth to the Superline earth tag and it's a silent as I could wish for.

Posted on: 02 August 2017 by Richard Dane
Bob the Builder posted:

I am using a Trichord Dino Phono amp with  an LP12 282 system and can sometimes get a bit of hum I have cured it temporarily by keeping the phono amp as far as possible from the 282/250 and also keeping the phono amp as far apart from its own psu as its cable will allow.  Obviously this isn't ideal and so this thread is also interesting to me as if I can avoid the hum by eartning the tonearm and my 282 together that would be brilliant.

Yes, the Superline definitely likes to have a bit of distance between it and anything digital or with a transformer.  In my main setup I have three low stacks of Fraim and the Superline is on the "brain" stack where there are no transformers and it's totally silent. Trying it on any shelf of either of the other stacks and you get a little bit of noise.