The second try: Naim Superline with Rega RP10

Posted by: ChrisBerlin on 16 October 2017

Hi,

it seems that I won't get happy with my new Naim Superline. After the problems with a used Superline, which could not be solved, I've gone for a new Superline. While I've been waiting for the delivery, I got a used Superline from my dealer. Everything was fine, no problems at all and an incredible sound. After waiting about two months I got my new Superline and installed it in the system. It is powered by a HiCap DR and from there it goes into a NAC 272.

A few minutes after power on I heard a noise - something like a white or pink noise. When I put the cartridge on the vinyl the noise was blown away. The first impuls from the RP 10 was enough to kill the noise. But after listening to two or three vinyls the noise comes up again. Sometimes only power down the whole system for 15 minutes could avoid the noise.

The first idea was that the new Superline has an error. Now I got an other Superline from my dealer than I got while waiting for my new one. Unfortunately the story was the same.

The HiCap, power supply of the RP 10 and the Superline are placed in one rack. The distance between each component is about 30 cm. The RP 10 is placed on a wall mount above the Superline. The distance is about 20 cm to the Superline placed on the top of the rack. So I don't think that the noise is produced by the transformers.

Do you have any ideas what I could do to avoid the noise?

Thanks for your advice!

Posted on: 16 October 2017 by yeti42

A few ideas:

Are your cartridge clips tight?

Does the 1nF plug reduce the noise?

Is there an earth lead from the arm? try connected to the earth tag on the SL and disconnected, any difference?

If you're not doing the collars up on the DIN plugs do so for now.

You have removed the transit screws?

I used to pick up Radio Moscow on mine, the 1nF plug helped reduce it. Oddly enough I've not been bothered since I put the system on Fraim instead of a steel and MDF Target style rack and I did try earthing the rack.

Posted on: 16 October 2017 by Richard Dane

The Superline is sensitive to transformers and digital kit that may be close by.  With my own Superline I had to put it in a transformer free stack to get rid of all noise - before it was in a stack with a DAC and it was very slightly noisy. Now, however it is absolutely silent with no signal - eerily so, even with the volume all the way up.  An incredible result for a phono stage.  

Otherwise, which inputs sockets are you using?  If it's the WBT Next Gens then using anything other than the matching RCA plugs you need to take care as you can get poor partial contact which gives noise - critical on some Rega arms where the earth is down the signal return on the left (?) channel.

Also try with the flying earth lead from the arm connected and disconnected (does the arm of the RP10 have an earth lead?? Maybe not - see above).  It's often better one way than another.

Posted on: 23 October 2017 by ChrisBerlin

Over the weekend I have been at home and tried some of your advices. Thank you very much!

I could avoid the noise. I have swapped the positions of the power supply of the Rega und the Superline. Now the Rega's power supply is placed under directly under the RP 10 which is placed on a wall mount. The distance between the two is about 20 cm. The Superline is placed in the middle of the rack between the Hicap on the bottom and the Rega's power supply on the top. The distance of the Superline to both other boxes is about 30-40 cm.

But I did not get rid of all noise. There is still a little bit of hum only on the left channel (hum, not noise). The hum gets louder, when I touch the tonearm with two fingers. The RP 10 has no separate earth lead. I have also read that it uses the cinch cable of the left channel as an earth lead. I have tried to use a separate earth lead from the tonearm to the Superline and from the tonearm to the chassis of the 272. In both cases the hum was turned up in volume.

Posted on: 23 October 2017 by Robiwan
ChrisBerlin posted:

Over the weekend I have been at home and tried some of your advices. Thank you very much!

I could avoid the noise. I have swapped the positions of the power supply of the Rega und the Superline. Now the Rega's power supply is placed under directly under the RP 10 which is placed on a wall mount. The distance between the two is about 20 cm. The Superline is placed in the middle of the rack between the Hicap on the bottom and the Rega's power supply on the top. The distance of the Superline to both other boxes is about 30-40 cm.

But I did not get rid of all noise. There is still a little bit of hum only on the left channel (hum, not noise). The hum gets louder, when I touch the tonearm with two fingers. The RP 10 has no separate earth lead. I have also read that it uses the cinch cable of the left channel as an earth lead. I have tried to use a separate earth lead from the tonearm to the Superline and from the tonearm to the chassis of the 272. In both cases the hum was turned up in volume.

there must be no extra noise when touching the tonearm. I think there is something wrong with the earthcable inside the arm which does not make good contact. 

Posted on: 23 October 2017 by yeti42

Whatever the earth switch on the 272 is set to try the other setting. Probably not going to work but worth a try.

Posted on: 23 October 2017 by Richard Dane

Chris, see my earlier post:

Otherwise, which inputs sockets are you using? If it's the WBT Next Gens then using anything other than the matching RCA plugs you need to take care as you can get poor partial contact which gives noise - critical on some Rega arms where the earth is down the signal return on the left (?) channel.

Which input sockets are you using?

Posted on: 23 October 2017 by ChrisBerlin

Hi Richard, yes, I am using the WBTs of the Superline. The Rega has cinch plugs that work nearly similar to the WBTs, especially seizing the RCA plugs. What's your advice? Do I have to change the RCA plugs from the RP 10?

Posted on: 23 October 2017 by Richard Dane

It may be an idea to try WBTs.  However, a quicker check might be to get some brand new 50 ohm BNC to RCA phono adaptors, which should be cheap, and try via the BNC input.  Presuming that the RCA plugs will get a good contact on the BNC adaptors you can at least check whether a poor earth contact is the issue before springing for either WBTs or a flying earth lead from the Rega arm.

n.b. Note I recommend brand new BNC adaptors.  The adaptors can break down pretty fast with use and give all sorts of problems, hence why brand new ones should at least minimise any false positive/negative results.

p.s. How well is your dealer helping you out here?

Posted on: 23 October 2017 by ChrisBerlin

My dealer is informed and tries to help. The problem is to find a date on a working day... I will ask my dealer for a adaptor. I think that this is a good idea. Perhaps it works and then I would get a hint from what the problem is caused. Thanks!

Posted on: 23 October 2017 by Richard Dane

Chris, if the adaptors work then that's great but don't rely on them long term.  Much better performance-wise to properly re-terminate the tonearm leads.  My first preference would be with 50 ohm BNC plugs over the WBT RCAs.

Posted on: 12 November 2017 by Richard Dane

Chris, how did it go? Did you manage to get to the bottom of the issue?

Posted on: 12 November 2017 by Skip

Be sure the plugs from the phono are seated properly in the Superline inputs.  I can't stress this enough.   I had this issue and it is disconcerting but with the plugs properly seated, it has been all good.

Posted on: 09 December 2017 by ChrisBerlin

Hello, sorry for the late answer. I was on holiday and no time to cover the problem. In the last week I have had assistence from my dealer. We have found the reason for the hum and the noise. It is the individual connection cable from the HC to the 272. It is a 5m 4to5 pin DIN cable. 

We have connected a better cable between HC and 272 and both problems are blown away. It is also possible to use the old and new interconnect on the HC’s two output sockets.  Both interconnects work probably. 

The new interconnect seems to work like an additional earth to avoid the hum. . 

Posted on: 09 December 2017 by Richard Dane

Ok thanks. 5m is way too long for the Hicap to drive properly without problems. If it were known earlier... anyway, glad you got it sorted. 

Posted on: 09 December 2017 by ayisgroovy

Good to hear all sorted. I was going to ask what Cap load are you using in the back of Superline? I use 1nF which is a good compromise between SQ and hiss/breakthrough. I did try 470pF which was too low and hiss intrusion in between tracks could be obviously audible. Try and give Peter Swain at Cymbiosis a call as he is very familiar with load plugs (ask about Z-foil) with respect to cartridge used. Peter has a wealth of knowledge on the Superline.