Hummmmmming LP12

Hi Ade, yes I am convinced it is an eathing problem. I have a very similar front end to you and had a lingo before moving to armageddon. The earth arrangement was modified by Audio Counsel during this move over. Basically with the Lingo fitted you need a point to earth from the deck, my dealer fit a earth cable to the deck and that came out of the lp12 into a 13 amp plug, just using the earth connection of this obviously. That was then plugged in alongside the power lead for the Lingo.

With armageddon PSU in place I believe the deck
has a main route to earth via the geddon and does not need such arrangement.

Best wishes

Gary

Thanks Fozz,
Did you change to an Armageddon after comparing it to a Lingo. Getting an Armageddon is something I have considered, but only because I thought it would solve any potential conflicts in the system. Does an Armageddon sound any different to a Lingo? I am aware it is 33rpm only.
Also, how does an Armageddon operate. A Lingo is permanently switched on and operated from a switch on the deck, but I think I saw this switch blanked off with an Armageddon'd deck.

Is it the addition of the Prefix that has resulted in my current problem, as the Lingo has been in the system for years, and it certainly hasn't always hummed, and was this earthing issue affecting performance of the system on vinyl and CD. I added the 52 to the system at the same time as the Prefix, which replaced an 82 with internal phono boards.

Ade

Definitely sounds like an earth problem associated with adding the Prefix to me.

The Geddon power switch is on the box thus removing the need for a switch on the deck, hence the blanking plug.

I demmed the Lingo(1) and Geddon (probably at the same place as Fozz) and clearly preferred the Geddon. Yes they sound different - the portrayal, prominence and emphasis of particular instruments can be surprisingly different in an a/b dem. Hard to say which is right, easier to say which is preferable - the Geddon (in my case). Can't speak for the Lingo2.

You might want to consider paying a good dealer to refit the Prefix and sort out the earthing problem.

Regards
Steve

Hi again Ade, yes I listened to an armageddoned deck at the dealers, and it went
hand in hand with a move to a Naimed LP12 for me, I moved from Ekos Lingo to Aro Armadeddon. Call it synergy or whatever you like but I found the two absolutely brilliant. Once I lived with the geddon I realised that the Lingo although very good, to me imparted a bit of a signiture on every record I played. The geddon made each LP take on much more of a) the recording ambience and thus very natural to listen to and b) the quality of the recording.

My mate runs Lingo and Itock and really enjoy
the change of listening to his system.

The geddon does blank off the switch on the LP12 and you then have a knob on a box that looks a bit like a hicap without the lit up naim logo.

Hope that helps

Gary

I suspect it's a Prefix installation problem rather than an earth loop caused by the use of a Lingo and a Naim CDP.

But the sensitivity to touch implies (to me) that the arm itself isn't earthed. In a conventional installation this would imply that the earth tag on the arm lead had become detached.

Don't know any detail about Prefix installation, perhaps a dealer is the simplest, safest bet?

Paul

Thanks for the replies.
I went into the dealers today to discuss, and it seems I need a different arm lead from Naim which has modified earthing, 2 earth leads or something like that. The owner wasn't there, so I'm going back in a couple of weeks, as I'm away 'till then, to discuss in more detail what exactly is needed.
I might even think about changing to an Armageddon!

On a slightly related note, has anyone had an S Prefix modified to a K, and how much did it cost. I am considering getting my old Troika rebuilt, and will take the opportunity to have my Prefix converted, and at the same time updated to the new RFI free spec.

Cheers
Ade

Yes I have just had my prefix modified. new black snaic and conversion from k to s and service and RF mod (new design or something) it came to 125.00. So simple conversion should be a lot cheaper I would expect. I went from Troika to xx2. Best wishes.

I seem to be going round in circles here. I've returned to the dealer, and it now seems he doesn't know why it's humming. He claims that the modified Lingo lead would have no effect, only having an influence on RFI, but my e-mail reply from Naim when I enquired said I probably needed the modified Lingo lead from Linn which cures the interference problems when a Prefix is fitted!!
As I mentioned earlier, I had what I thought was the modified Lingo lead (CONN401E) fitted a couple of years ago when my previous lead got damaged. As this wasn't to fix some kind of interference problem, I didn't think too much about it, but now I'm concerned the wrong lead, the CONN401 was fitted.
If anyone has the CONN401E fitted, could they confirm for me whether the cable is actually marked CONN401E, as mine just has CONN401 printed on it. I paid over £70 for this lead instead of the much cheaper CONN401, but the dealer says that if it was the wrong lead, even though he fitted it, I'll have to buy another one.

Cheers
Ade

Ade,

He's not a good dealer then.

I made that mistake with a Chord Chrysalis i/c. My dealer refunded me the money (well actually, he credited the cost to another purchase I was making anyway.)

If he refuses to carry the can for poor advice/installation, you should mention "Trading Standards" in passing. It doesn't usually come to that though if you put up a bit of a fight (diplomatically) and suggest where your future business may go...

Regards,

Steve.

I would like to establish for certain that it's the Lingo lead that is incorrect, as I specifically asked for the more expensive CONN401E, since I had read here that it was designed for Naim systems, and even though I didn't have an interference problem at the time, I thought it would prevent any future problems. It was fitted a couple of years ago, but it's only very recently I've added a Prefix, but the dealers attitude seems to be that because I've fitted a second hand Prefix, it's not his problem.
This is why I need to establish that he fitted the wrong lead originally, which is the root of the problem. He says that the Lingo lead won't solve it, and even if it is the wrong lead, Linn must have sent him the wrong one and it's too late to do anything about it now (I like to think he would have noticed at the time!) but Naim say I need a special Lingo lead to solve it. Who is right? And is this the lead that I'm supposed to have anyway.
I couldn't make a serious argument with the dealer because I'm not sure that I've got the wrong lead (Anyone with a CONN401E, please confirm whether it is labelled as such).
I e-mailed Linn to try to find out. I got an automated reply, stating that technical queries can take up to 5 days to answer. Richard at Naim replied to my e-mail within a couple of hours!! If only Naim made turntables!!
Please can someone help me identify whether I have the right or wrong Lingo lead, which is the first thing I need to establish

Cheers
Ade

Ade,

I believe there may be a difference between the earthing configuration of a Prefix and non-Prefix LP12.

A 52 must have only one earthed source connected (one that connects signal 0V to mains earth).

If you have a Naim CDP, this does the earthing, so the LP12 should not do this.

If I understand correctly, the Conn401/E disconnects the earth on the input to the LP12. This then allows the LP12 earth wire to earth the arm (and subchassis?) & cart through the 52 & back to the CDP. Basically, the break in the earth is between Lingo & LP12.

I think that the Prefix may disconnect the earth, so that you have now disconnected the arm & cart from both Lingo earth & 52 earth. If this is the case then your dealer is right; your new Prefix has upset what was correct before. If so, you presumably need to revert back to your old Conn/401. (Hope you kept it).

I would suggest that you call Mark Raggett on Monday and discuss this with him.

BTW, this whole earthing business is incredibly arcane, and I bet the majority of dealers wouldn't know anything about it.

cheers, Martin

E-mail:- MartinPayne (at) Dial.Pipex.com. Put "Naim" in the title.

Thanks Martin,
Thing is the dealer isn't right because he doesn't know why it hums. He states that whichever Lingo lead I have will not solve this, as the Lingo lead was modified to address RFI issues, although in fairness he has apparently never sold an Armageddon, and only a couple of Prefix's (I found this amazing because he's been a Linn/Naim dealer since well before I first went there in about 1990), so his experience with these is limited to say the least.
I can't be the only person with a Prefix'd and Lingo'd LP12, so I'm surprised I'm having so much trouble trying to get to the bottom of it. The dealer tells me to contact Naim because it's a Prefix (which he didn't fit, so he's not interested), and Naim tell me I need a modified Linn lead, which I thought I had, but the dealer states it won't cure it anyway AAARRRGGHHH!!!

Ade

It seems to me that you have the 'right' Lingo lead, but subsequent to the installation of the Prefix it has become the 'wrong' one and your arm/turntable are no longer earthed. This isn't a safety issue due to the Lingo isolating the turntable from the mains, but it is clearly a performance one.

Any self-respecting Linn dealer would sort this out regardless of who installed the Prefix. If you're prepared to travel a little then I'm sure Frank at Overture in Banbury could fix it.

Paul

Thanks Paul,
Yes, a new dealer is certainly something I'm going to have to look at. Preferably a knowledgeable both Naim and Linn dealer. The dealer I bought Naim kit from until last year is no longer a Naim dealer, and the one I'm currently dealing with is both Linn and Naim. I originally bought my LP12/Lingo/Ittock and SBL's from him, and my previous 72/140, but he still doesn't seem that interested in helping me out. 'That's what you get when you buy second-hand' was the response!
I simply would not have been able to afford some of my equipment if I hadn't gone second-hand, and to be fair I said to him months ago if he gets a 52 or cds2 in from someone upgrading, to let me know. He certainly didn't seem to mind when I bought second hand SBL's from him from someone who had upgraded to DBL's.

An Armageddon is something I've considered for some time, but I will be reluctant to give him my business now.

Now, if anyone can confirm that a CONN401/E is actually labelled 'CONN401/E' and not 'CONN401', I will at least be able to identify which one I've got, and whether it's the wrong one.

Thanks for the recommendation re Overture, anyone any other suggestions for good Linn/Naim dealers around the Birmingham area.

Cheers
Ade

Ade,

does the hum on phono go away if you unplug the cd player from the amp??
if so you have an earth loop.

do you have a lingo or lingo2 ??
CONN401/E is required with lingo2 only if using
naim amps and no naim cd player.

Keithy,
No it doesn't go away or reduce with the CDS2 disconnected from the 52, and it's a Lingo, not a Lingo 2.

Ade

Ade,

i'm confused then!

if you need to change from conn401/e to conn401 you can just disconnect the earth (inside the sondek) without having to completely replace with a conn401 cable

i do have a spare conn401 cable you could
have for a lot less than a new one!

HTH

What is the physical difference between Conn401/e and Conn401, so I can tell exactly which one I've got.
The Conn401/e cost much more than the Conn401, like twice as much. If the only difference is an extra earth wire, as your suggestion above implies, that is a rip-off of epic proportions!

Ade

the only difference IS the earth connection.
i had to buy a conn401/e cable myself recently
linn had initially "never heard of it" and it was only after my dealer spoke to naim that they were able to supply it!

Ade,

This is confusing, isn't it?

The whole LP12 earthing issue is messy and exacerbated if using mixtures of Naim / Linn (i.e. Lingo / Prefix).

I'll try to clarify things and give you a way of determining whether you have the CONN401/E.

With an LP12 and no Lingo (i.e. Basik or Valhalla PSU) the chassis / top-plate of the deck is earthed to the mains, via the incoming mains lead.

The arm has an earth lead that connects the arm to the chassis and another earth lead that goes to the amp binding post.

Add the Lingo with the standard lead and there is no longer a connection to mains earth at the deck / top-plate and consequently no mains earth connection to the arm lead.

For amps such as Naim, that are star-earthed, you need this connection from signal 0V to mains earth at one point only.

If you have a Naim CD player the connection is made there, so no need for the CONN401/E - the turntable is effectively earthed in a connection that runs CDP - Preamp binding post - Arm earth lead - LP12 arm / chassis / top plate.

Now, add a Prefix and things get more complex. The Prefix only connects to the arm / cartridge, the earth wire that runs from it to the binding post of your 52 only connects to the Prefix itself - the connection that existed on the old arm cable (arm / chassis / top-plate / earth wire to preamp) is now lost.

This now means the LP12 top-plate / chassis is floating. It's not a safety issue because of the isolation the Lingo provides, but it may casue problems with, for example, the field from the motor.

In this event you need the CONN401/E to earth the chassis / top plate of the deck.

If you have a meter, with a continuity check, it's easy to determine whether you have the CONN401/E.

First unplug the Lingo from the mains, but leave the LP12 plugged in.

Connect one meter probe to the earth pin of the mains inlet socket and then touch the other against the top-plate. If you have a connection / continuity you have the /E lead.

Another way to check would be to look under the LP12. With the mains unplugged and the base removed (don't tilt the deck to do this) look for where the Lingo lead enters the deck. On a /E lead there should be a connection from the lead that runs to the various chassis parts (sub-chassis etc.) - a standard lead will only connect to the plug on the interface board that connects to the motor / switch.

Hope this helps, Naim are right that you do need the CONN401/E and I suspect that you don't have it at present.

quote:

---

The Conn401/e cost much more than the Conn401, like twice as much. If the only difference is an extra earth wire, as your suggestion above implies, that is a rip-off of epic proportions!

---

It is steep isn't it, although IIRC it's less of an earth 'wire' more of a screened lead which would make wiring more complicated. The earth connects at the Lingo end to the body of the plug and at the LP12 to the chassis, requiring surprising additional labour to terminate neatly to the screen.

When I get a spare moment I'll publish DIY details - all the parts are readily available for <£10-15 + a an hour or so of time.

Andy.

Andrew, thanks very much for that.
Hopefully this is a picture of the underside of my LP12, which may help identify which lead I have, as I'm still not sure! I think it may well be the CONN401/E

Cheers
Ade

Andy has said much the same as me, but I had believed that Conn401/E lifted the earth and it turns out that it's the other way around.

It sounds like you have the right lead. Given your recent experience, I wonder if your dealer has installed it correctly?

cheers, Martin

E-mail:- MartinPayne (at) Dial.Pipex.com. Put "Naim" in the title.

Ade,

Looks like the /E lead to me, the green / yellow earth wire is present.

The problem though may be it's not earthing all it needs to. The green / yellow wire is going to the strut supporting the Lingo interface board, but there needs to be a connection from here to the other metal parts of the deck.

I can see a single black earth lead to the top-right of the picture, I can't remember from memory the arrangement, but ultimately you want a connection between the 401/E earth wire the sub-chassis and the top plate. The top-plate may be earthed via that bolt anyway.

If you don't have a Naim CDP this should also possibly connect to the prefix earth wire too, but not so sure of this - without the 401/E doing this will result in horrendous hum from the motor!

I suggest another chat to Naim for more specific advice.

Andy.

I spoke with Naim today, and was advised to try disconnecting the earth lead in the mains plug, which may cure an earth loop.
This did not cure it, but in the process I actually discovered that the hum is present when the deck is unplugged from the Lingo, and is totally unpowered, so the only connection the LP12 has is to the 52 via the Prefix. In fact the humming is the same whether the Lingo is connected to the LP12 or not. Does this help pinpoint the problem to anyone more knowledgeable than me?

Ade