Linn Lingo 4 ground problem and fix

Hardware and software, modifications and DIY

Moderator: Staff

User avatar
lejonklou
Administrator
Administrator
Posts: 6524
Joined: 2007-01-30 10:38
Location: Sweden
Contact:

Linn Lingo 4 ground problem and fix

Post by lejonklou »

PREFACE:
Some of you will know this already, because you asked for more info that I hinted at in the "Lingo 1 recap result" thread in the "On the Inside" section of this forum. I am now making it public, because I have learned that Linn have recognized the problem and will likely present a fix.

I am also posting it because the magnitude of the problem varies with which phono stage you are using. The first time I listened to a Lingo 4, I was using a Slipsik 7. The ground problem in Lingo 4 then results in a faint hum in the speakers which you may not notice unless you really listen for it. It also gives a loss of musicality, which caused me to be underwhelmed with the performance. Now that I've tested Lingo 4 with an Entity MC stage, the hum is more pronounced, so it becomes more likely you will notice that something is wrong. The loss of musicality is still evident, plus an annoying hum in the speakers. When your Lingo 4 is fixed, you will not only get a more musical LP12, but it will also be hum free.

THE ISSUE IN DETAIL:
Normally, your LP12 top plate, crossbrace, inner platter, Trampolin 2 (if you have one) and arm are connected to the ground screw of the phono stage (or the amplifier equipped with a phono stage) through the ground wire in the tone arm cable. That's the thin wire in between the thicker left and right coaxial cables of the tone arm cable. On some arm cables, the wire is separated from left and right cables.

This is the optimal way to do it, as it keeps the metal parts of your LP12 at the same potential as the ground in your phono stage (or amp with internal phono stage). So the music traveling from your cartridge to the phono stage is surrounded by a ground potential, which protects the signals from interference.

In the installation manual of Lingo 4, there is a mention of an optional link called LK1 on the circuit board inside the LP12. What LK1 does is to connect the chassis of the LP12 to the mains ground of the external Lingo 4 power supply (the screen of the cable from the power supply to the Lingo 4 board inside the LP12 carries the ground). This link is normally not used - you only connect it if for some reason, your LP12 isn't grounded through the ground wire of the tone arm cable. There are for instance some arm cables that don't have a ground wire - in that unusual scenario you might notice a hum in your speakers and the solution then is to add a jumper to link LK1 on the Lingo 4 board. Then your ungrounded LP12 becomes grounded to the Lingo 4 external power supply.

The problem is that the XLR connector that Linn are using on the Lingo 4 board (which receives power from the external power supply) has its metal front plate connected to the ground pin of the XLR through an extra metal link on the side of the connector. This metal link is designed to hook into the screw that holds the XLR to the panel. The result is that the optional ground connection that link LK1 provides is by mistake always present. So with a Lingo 4 inside your LP12, your top plate, inner platter, arm, etc are now grounded both to the Lingo 4 external power supply (and there to its mains ground) and the phono stage through the arm ground wire (also to mains ground). This creates a big ground loop, which causes loss of sound quality. In addition it causes either a hum through the loudspeaker (can be faint or strong, depending on the phono stage), some high frequency noise from the Lingo 4 circuit, or both.

The solution is to cut the link of the XLR connector, as shown in the photos below. I recommend that you let your retailer do this and let him know that Linn have accepted it as a fix to the problem. Linn might also choose to solve it by exchanging the metal standoffs that hold the Lingo 4 case inside your LP12 for plastic standoffs, which would isolate the case from the LP12 metal parts. Either solution works.

You need to remove the four screws holding the Lingo 4 unit to the crossbrace and preferably the Lingo 4 board from its metal case (I think it's 4 screws plus the two holding the XLR). Use a sharp pair of cutting pliers, gently cut it off (you might need to clip several times to chew through it) and pull it out. No harm is done to your Lingo 4 or LP12. All you are doing is disconnecting the circuit ground from the metal front plate of the XLR connector (which should not be grounded as it shorts against the metal parts of the LP12).

After I discovered this fault and cut the link on the XLR, my initial disappointment with Lingo 4 vanished. It really is a great motor controller for the LP12!

Image
The XLR connector with its metal front plate. Red arrow points to the ground link that you are about to cut. You can see the tip of the link in the left screw hole of the XLR, bent to the right against the metal front plate.

Image
This is the removed piece. It ends in the screw hole and can be pulled out without any force required. Notice the dents on the left, pointy side - those are from the metal screw digging into it. And that is how the entire metal housing becomes connected, by mistake, to the ground of the Lingo 4 circuit board. Which is the option that link LK1 provides!

Image
This is what it looks like after the cut. The result? Lingo 4 performing as it should. Link LK1 at the bottom right is available if you should ever need this type of grounding.
User avatar
Tony Tune-age
Very active member
Very active member
Posts: 1579
Joined: 2009-12-19 19:07
Location: United States

Re: Linn Lingo 4 ground problem and fix

Post by Tony Tune-age »

That's a great report Lejonklou, very informative indeed. I'm glad Linn recognizes there is a legitimate problem and will make corrections. Of course I'm still waiting for Linn to recognize the Trampolin and Radikal motor problem, and then make proper corrections for that as well.

Cheers
Tony Tune-age
User avatar
ThomasOK
Very active member
Very active member
Posts: 4358
Joined: 2007-02-02 18:41
Location: United States
Contact:

Re: Linn Lingo 4 ground problem and fix

Post by ThomasOK »

I meant to weigh in on this earlier but forgot after I read it. Once Fredrik alerted me to this I brought my own Lingo4/LP12 into work and verified the grounding problem. I then liaised with Linn service informing them of the problem, including photos of my meter showing the connection. Once they let me know what they have come up with as a permanent solution I will let you know.
Last edited by ThomasOK on 2020-01-17 23:18, edited 2 times in total.
The LP12 Whisperer
Manufacturer, Distributor, Retailer and above all lover of music.
Donald
Active Member
Active Member
Posts: 64
Joined: 2013-08-26 22:25
Location: Glasgow

Re: Linn Lingo 4 ground problem and fix

Post by Donald »

As a Lingo 4 owner I was a bit surprised when I read this Thread as I was unaware of any ground problem. I noted that this presents itself as a "...faint hum in the speakers" and a " ... loss of musicality". I can't say that I have experienced either but of course some more detailed listening will be required? It may be that this problem is more pronounced with certain phono stages, as alluded to, with my own observations being limited to the Akurate DSM phono card (MM and MC) and the Linn Linto.

I was heartened, however, to read that " ...that Linn have recognized the problem and will likely present a fix. " - after learning this I sent off an email to helpine@linn.co.uk asking when this might be available and Customer Support responded:-

"We have no control of the information posted on HiFi Forum websites and as such cannot make any comment on the contents posted within. If you have a problem with your Lingo 4 power supply, please contact your Linn retailer who can assist you further."

To me this doesn't seem to be anywhere near recognising the problem, if one exists, let alone presenting a fix!

So before I go off and contemplate cutting the link of the XLR connector I'd really appreciate some clarity on this issue?

As a footnote I did raise a smile - when Linn did have control over information posted on a HiFi Forum they chose to close it down?
LP12/Kore/T2/Akito/Adikt/L4|Akurate DSM|Akurate Exaktbox 10|2 x Akurate 4200/1|Keilidhs
User avatar
lejonklou
Administrator
Administrator
Posts: 6524
Joined: 2007-01-30 10:38
Location: Sweden
Contact:

Re: Linn Lingo 4 ground problem and fix

Post by lejonklou »

Donald wrote: 2019-12-22 18:19 As a Lingo 4 owner I was a bit surprised when I read this Thread as I was unaware of any ground problem. I noted that this presents itself as a "...faint hum in the speakers" and a " ... loss of musicality". I can't say that I have experienced either but of course some more detailed listening will be required? It may be that this problem is more pronounced with certain phono stages, as alluded to, with my own observations being limited to the Akurate DSM phono card (MM and MC) and the Linn Linto.

I was heartened, however, to read that " ...that Linn have recognized the problem and will likely present a fix. " - after learning this I sent off an email to helpine@linn.co.uk asking when this might be available and Customer Support responded:-

"We have no control of the information posted on HiFi Forum websites and as such cannot make any comment on the contents posted within. If you have a problem with your Lingo 4 power supply, please contact your Linn retailer who can assist you further."

To me this doesn't seem to be anywhere near recognising the problem, if one exists, let alone presenting a fix!

So before I go off and contemplate cutting the link of the XLR connector I'd really appreciate some clarity on this issue?

As a footnote I did raise a smile - when Linn did have control over information posted on a HiFi Forum they chose to close it down?
Have you cut the link yet, Donald?

You'll be stunned by the difference it makes.
User avatar
Moomintroll
Active member
Active member
Posts: 166
Joined: 2007-04-22 21:52
Location: UK

Re: Linn Lingo 4 ground problem and fix

Post by Moomintroll »

Anyone aware of Linn sending out a Service Bulletin for this issue, yet?

‘troll
User avatar
ThomasOK
Very active member
Very active member
Posts: 4358
Joined: 2007-02-02 18:41
Location: United States
Contact:

Re: Linn Lingo 4 ground problem and fix

Post by ThomasOK »

I have received nothing on it so far.
The LP12 Whisperer
Manufacturer, Distributor, Retailer and above all lover of music.
User avatar
Moomintroll
Active member
Active member
Posts: 166
Joined: 2007-04-22 21:52
Location: UK

Re: Linn Lingo 4 ground problem and fix

Post by Moomintroll »

Thank you.

‘troll
sktn77a
Active member
Active member
Posts: 103
Joined: 2020-10-22 00:47

Re: Linn Lingo 4 ground problem and fix

Post by sktn77a »

Was there ever an update on this issue? Have all Lingo 4 owners on this forum clipped the offending connection? How about Linn - have they revised the design of the XLR ground connection or do they still have their heads stuck in their............ sand?
Keith
LP12, Ekos, VM760, Slipsik 7.1, NDX2, 252, 250, Aerial 5B, LS3/5a, Harbeth M30, Gallo TR3D
User avatar
ThomasOK
Very active member
Very active member
Posts: 4358
Joined: 2007-02-02 18:41
Location: United States
Contact:

Re: Linn Lingo 4 ground problem and fix

Post by ThomasOK »

I installed a new Lingo 4 about a month ago and there had been no change so I still had to clip out the section of the XLR ground connection. I have not heard any more from their service department indicating any plans either.
The LP12 Whisperer
Manufacturer, Distributor, Retailer and above all lover of music.
Spannko
Very active member
Very active member
Posts: 2292
Joined: 2008-01-24 21:46
Location: North East of The Black Country, UK

Re: Linn Lingo 4 ground problem and fix

Post by Spannko »

That’s very saddening to hear.
Stephan
Member
Member
Posts: 25
Joined: 2016-02-11 10:18

Re: Linn Lingo 4 ground problem and fix

Post by Stephan »

In our company we have the following routine:

1: Information about potential problem is received from: customer/after sales/production ...
2: We evaluate the information within one/a couple of days and decide for the following:
-Recall of product (this is the panic situation)
-Production stop until implementing ”waiver” wich is basically a written instruction describing the modification needed
-Continued production and update for next release (this can take more than a year)
-Decide to do nothing. Reason for this decision can be that:
the issue is minor, much resources are needed to fix the problem or the product will be discontinued...

In this case Linn could, and should have stopped production and made a ”waiver” to fix the issue.
Basically a meeting with people from marketing, supply chain and engineering is needed, a couple of decision have to be made and an instruction written and introduced to the production line

How can this not have happened in almost a year!
User avatar
Ron The Mon
Very active member
Very active member
Posts: 301
Joined: 2014-07-17 17:17
Location: Detroit
Contact:

The Fix Is In

Post by Ron The Mon »

Stephan wrote: 2020-11-07 23:27 In our company we have the following routine:

1: Information about potential problem is received from: customer/after sales/production ...
2: We evaluate the information within one/a couple of days and decide for the following:
-Recall of product (this is the panic situation)
-Production stop until implementing ”waiver” wich is basically a written instruction describing the modification needed
-Continued production and update for next release (this can take more than a year)
-Decide to do nothing. Reason for this decision can be that:
the issue is minor, much resources are needed to fix the problem or the product will be discontinued...

In this case Linn could, and should have stopped production and made a ”waiver” to fix the issue.
Basically a meeting with people from marketing, supply chain and engineering is needed, a couple of decision have to be made and an instruction written and introduced to the production line

How can this not have happened in almost a year!
It happened because Linn have a very active online Forum which requires all manufacturing, design, and marketing employees to manage.
Defender
Very active member
Very active member
Posts: 1266
Joined: 2018-02-14 22:35

Re: Linn Lingo 4 ground problem and fix

Post by Defender »

Hi Ron I would like to understand your comment better - the Linn Forum is off since more than a year so all the departments would have the time.
I might got your post wrong but Linn should just fix it - there is no excuse to not fix it not for the Lingo issue nor for the Radikal issue.
...maybe I just didnt got your joke ;)
User avatar
ThomasOK
Very active member
Very active member
Posts: 4358
Joined: 2007-02-02 18:41
Location: United States
Contact:

Re: Linn Lingo 4 ground problem and fix

Post by ThomasOK »

Actually some good news here. I was talking a couple of days ago to the Linn setup guy at another US Linn dealer. He calls me from time to time to chit chat and occasionally for advice. He had just received what he called the "new" Lingo 4. It turns out Linn has made two changes to the kit of parts. One is to shorten the standoffs as the Lingo 4 won't fit into some of the shorter plinths out there (similar problem to the Radikal motor/Trampolin but worse). The other change is that it now comes with two plastic standoffs and appropriate screws to take care of the grounding problem. (This was one of the suggestions I made to them to fix the problem so I am glad it worked.) I have not gotten one of the newer Lingo 4s in yet but I did find that Linn had updated the installation instructions earlier this month with the proper placement of the plastic parts clearly described. So our concerns have been addressed. Thanks to Linn for taking care of this.
The LP12 Whisperer
Manufacturer, Distributor, Retailer and above all lover of music.
User avatar
Tendaberry
Very active member
Very active member
Posts: 982
Joined: 2010-08-30 16:08
Location: Hamburg

Re: Linn Lingo 4 ground problem and fix

Post by Tendaberry »

Yes, this is what I heard from my delaer as well, good news!
Defender
Very active member
Very active member
Posts: 1266
Joined: 2018-02-14 22:35

Re: Linn Lingo 4 ground problem and fix

Post by Defender »

thats good news in a world where good news are rare :)
Pedro
Active Member
Active Member
Posts: 58
Joined: 2007-02-02 22:37
Location: Germany

Re: Linn Lingo 4 ground problem and fix

Post by Pedro »

I have installed a Lingo4 today. It replaced a Majik Power Supply.
In the installation instructions a change is pointed out. Possibly it solves the grounding problem Frederik pointed out.
Take a look at the photos.
LINGO 4 INSTALLATION INSTRUCTIONS (Seite 6).jpg
Lingo4-Board and Traverse.jpg
I
Lingo4 board.jpg


After the Upgrade the LP12 sounded very musical, the customer was thrilled! - What more could you want!
You do not have the required permissions to view the files attached to this post.
Klimax LP12 (Rad 2; Ekst), Urika II, NG-KSH, 2x KEB (Organik), Silvers, 2x A4200, K400, Komris
sktn77a
Active member
Active member
Posts: 103
Joined: 2020-10-22 00:47

Re: Linn Lingo 4 ground problem and fix

Post by sktn77a »

Sorry to resurrect an old thread but to anyone who has installed a Lingo 4 recently:

1. Does a new cross brace/grounding strap come in the Lingo 4 package?

2. I assumed all of the standoffs would be the new plastic but see that two are still metal. Is this correct? Does this not maintain the ground loop?

Thanks in advance.
Keith
LP12, Ekos, VM760, Slipsik 7.1, NDX2, 252, 250, Aerial 5B, LS3/5a, Harbeth M30, Gallo TR3D
User avatar
ThomasOK
Very active member
Very active member
Posts: 4358
Joined: 2007-02-02 18:41
Location: United States
Contact:

Re: Linn Lingo 4 ground problem and fix

Post by ThomasOK »

The cross brace is not included in the package, it must be ordered separately. Personally I feel Linn really should include it as the majority of LP12s the Lingo 4 will be installed in will need it. Only new LP12s and relatively recent Majik LP12s and others made within the last few years will already have the right cross brace. But then they left nuts and washers out of the Cirkus bearing upgrade kit and didn't finally ad them until the Karousel came out. Better 27 years late than never?

I haven't yet installed a Lingo 4 with the plastic standoffs but my belief is that only two would be necessary to avoid the grounding problem if positioned properly. They would need to be diagonally opposed as that is how the board and it's shield is laid out. The images above show them being installed that way. That is what I had recommended to Linn when we discussed it.
The LP12 Whisperer
Manufacturer, Distributor, Retailer and above all lover of music.
sktn77a
Active member
Active member
Posts: 103
Joined: 2020-10-22 00:47

Re: Linn Lingo 4 ground problem and fix

Post by sktn77a »

Thanks Tom. Pretty much what I thought but it's nice to get knowledgeable confirmations for us poor souls in the Linn backwoods! ;)
Keith
LP12, Ekos, VM760, Slipsik 7.1, NDX2, 252, 250, Aerial 5B, LS3/5a, Harbeth M30, Gallo TR3D
Pedro
Active Member
Active Member
Posts: 58
Joined: 2007-02-02 22:37
Location: Germany

Re: Linn Lingo 4 ground problem and fix

Post by Pedro »

In the Lingo 4 conversion kit that has now been delivered, 2 standoffs are made of plastic and 2 of metal.
They are all 15 mm long.
Klimax LP12 (Rad 2; Ekst), Urika II, NG-KSH, 2x KEB (Organik), Silvers, 2x A4200, K400, Komris
sktn77a
Active member
Active member
Posts: 103
Joined: 2020-10-22 00:47

Re: Linn Lingo 4 ground problem and fix

Post by sktn77a »

Thanks Pedro, buona giornata!

EDIT Jan 9, 2021: Hey I just noticed something. The nylon standoffs on the Majik crossbar (grounding strap) are in different positions than in the Linn instructions (transposed). Did you change them around before fitting the Lingo 4?
Keith
LP12, Ekos, VM760, Slipsik 7.1, NDX2, 252, 250, Aerial 5B, LS3/5a, Harbeth M30, Gallo TR3D
sktn77a
Active member
Active member
Posts: 103
Joined: 2020-10-22 00:47

Re: Linn Lingo 4 ground problem and fix

Post by sktn77a »

Bump to the top! @thomasOK, @ Pedro

EDIT Jan 9, 2021: Hey I just noticed something. The nylon standoffs on the Majik crossbar (grounding strap) are in different positions than in the Linn instructions (transposed). Did you change them around before fitting the Lingo 4?
Keith
LP12, Ekos, VM760, Slipsik 7.1, NDX2, 252, 250, Aerial 5B, LS3/5a, Harbeth M30, Gallo TR3D
Pedro
Active Member
Active Member
Posts: 58
Joined: 2007-02-02 22:37
Location: Germany

Re: Linn Lingo 4 ground problem and fix

Post by Pedro »

Hello sktn,

You're right. The metal standoffs need to be changed.

For my second picture I had put the lingo board with metal cover (as it came out of the box) on the table and the Majik Crossbar in front of it. I then screwed in the two plastic standoffs to illustrate the difference in material of the standoffs.

I assume that Linn takes the two metal standoffs for the screw connection to the metal cover for shipping the Lingo, because these metal standoffs hold the board better in position.
This makes transport safer.

During assembly, I screwed in the standoffs exactly according to Linn's installation instructions.
Klimax LP12 (Rad 2; Ekst), Urika II, NG-KSH, 2x KEB (Organik), Silvers, 2x A4200, K400, Komris
Post Reply