Klimax DS torque recommendations

[Rufus McDufus]

I've got a new Wera torque screwdriver set (can't find a decent looking Sturtevant Richmont on eBay for a decent price right now and Amazon UK have some great prices on the Wera if anyone's interested).

Does anyone have their torque recommendations to hand ( ThomasOK?). I gather the default board torques are around 0.4 NM generally on Klimax gear? I want to very careful not to over-tighten obviously so want some ball-park recommendations to get some idea of what's possible.

I have a KK/1 too so will probably try applying the same techniques...

[Nicolav]

I've set 0.9 nm on my KDS/1 using a SR. After 48 h of settlement the DS sounds is more right and in tune. From factory upgrade the screws had differents torque value each from others, from 0,5 to 1.0 nm.
Beware to try higher value than 1.0 nm to avoid damage to circuit board!

[Rufus McDufus]

Thanks Nicolav! This is 0.9Nm just on the circuit boards right?
I'm maybe not expecting case torques to make such a difference but at least I don't have to be quite so wary about over-tightening the case screws.
I tend to find Linn don't seem to pay much attention to screw torques...

[Nicolav]

Thanks Nicolav! This is 0.9Nm just on the circuit boards right?
I'm maybe not expecting case torques to make such a difference but at least I don't have to be quite so wary about over-tightening the case screws.
I tend to find Linn don't seem to pay much attention to screw torques...

Yes, just on circuit board.
You may also check the torque of heart bolt. It should set between 3.0 (minimum) and 3.5 nm, If is under 3.0 is too loose and musicality are affected too.
Generally on klimax gear Linn use 1.0 nm for the screws of the circuit boards.

[Music Lover]

You may also check the torque of heart bolt.

The Torx Screw on the Alu chassis?

[lejonklou]

I think Nicolav is referring to the mains ground bolt.

[Nicolav]

I think Nicolav is referring to the mains ground bolt.

Thanks for clarification Fredrik!
Yes, I mean the main ground ex bolt on the alu chassis.
The torque value on this bolt is very noticeable on KK too.

[lejonklou]

I agree with you, Nicolav. I first heard about this very high torque on the mains ground earlier this year. I have personally never tried values that high on any fastener inside an electronic product. From what I've heard it only works on the mains ground in Klimax cases. Or am I wrong?

On my own products, the optimal torque on the mains ground nut is slightly above 0.8 Nm. Going above that has resulted in a stiffer and worse sound, but I've only gone as far as somewhere between 2.5 and 3 Nm. I might have to try above 3 Nm to see if another peak appears up there, but I suspect not.

[Nicolav]

I agree with you, Nicolav. I first heard about this very high torque on the mains ground earlier this year. I have personally never tried values that high on any fastener inside an electronic product. From what I've heard it only works on the mains ground in Klimax cases. Or am I wrong?

On my own products, the optimal torque on the mains ground nut is slightly above 0.8 Nm. Going above that has resulted in a stiffer and worse sound, but I've only gone as far as somewhere between 2.5 and 3 Nm. I might have to try above 3 Nm to see if another peak appears up there, but I suspect not.

Fredrick, to be onest, these optimal torque value are not found by me but by Paolo and afterwards I agreed with his findings.
On KDS and KK the factory torque value is already high (around 2,9-3,0 nm). Trying increasing this value up to 3.3-3,5 nm Paolo and I have noticed a significant improvement of the musicality of Klimax units.

[ThomasOK]

Paolo is the first one I am aware of who suggested the musical improvement of the higher torques. I tested the values he came up with on a couple of samples and I agree with most of them. The best torque I found for the main board and control board on the KK is 1.0Nm -1 notch (on the SR driver - equal to just about 1.5 hundredths of a Nm below 1). 1.0Nm even was really close but the one notch below improved it a bit more. Of course this will depend on the specific driver as they can easily be off more than this but it points out the value of checking settings near the recommended setting in the smallest increments possible. A word of warning however - you don't want to tighten and loosen these fasteners too often at these torque levels as you can damage the contacts on the circuit boards. On the KK I recommend finding the most musical torques for the control board (upper when units is upside down) and then removing the control board (making SURE the power is disconnected) and torqueing the audio board to the same settings (needs a 5.5mm nut driver bit) and replacing the control board. I have found the optimal settings for these two to be the same.

On the ground post I did try the higher range Paolo recommended, around 3.4Nm, but I prefer the setting I had found previously which is exactly 2.0Nm.

Other torques I have found to be the most musical on a KK:

Power supply cover: .4nM + 5 notches
Back panel to chassis: .8nM + 2 notches
Bottom of chassis to top: .8nM - 2 notches

I have not been able to verify these on a KDS but expect they are likely to be the same except for the power supply cover which is plastic on the KK.

[anthony]

Paolo is the first one I am aware of who suggested the musical improvement of the higher torques. I tested the values he came up with on a couple of samples and I agree with most of them. The best torque I found for the main board and control board on the KK is 1.0Nm -1 notch (on the SR driver - equal to just about 1.5 hundredths of a Nm below 1). 1.0Nm even was really close but the one notch below improved it a bit more. Of course this will depend on the specific driver as they can easily be off more than this but it points out the value of checking settings near the recommended setting in the smallest increments possible. A word of warning however - you don't want to tighten and loosen these fasteners too often at these torque levels as you can damage the contacts on the circuit boards. On the KK I recommend finding the most musical torques for the control board (upper when units is upside down) and then removing the control board (making SURE the power is disconnected) and torqueing the audio board to the same settings (needs a 5.5mm nut driver bit) and replacing the control board. I have found the optimal settings for these two to be the same.

On the ground post I did try the higher range Paolo recommended, around 3.4Nm, but I prefer the setting I had found previously which is exactly 2.0Nm.

Other torques I have found to be the most musical on a KK:

Power supply cover: .4nM + 5 notches
Back panel to chassis: .8nM + 2 notches
Bottom of chassis to top: .8nM - 2 notches

I have not been able to verify these on a KDS but expect they are likely to be the same except for the power supply cover which is plastic on the KK.

Must admit, find the torque on the plastic cover, making a difference, difficult to understand.
Do you think there is an explanation for this?

[lejonklou]

In my opinion there are a lot of mechanical adjustments that are difficult to understand.

Ever placed a piece of paper under a foot to stop a unit from rocking? Makes a difference. Ever compared that piece of paper with a thin piece of plastic? Makes a difference too! So it wasn't just the rocking...

Same thing in electronics. A lot of it is logical, but some things go against common sense. Details that turn out to be important although they shouldn't be. Or the magnitude of the importance seems way out of proportion.

Sure there's an explanation. But I won't waste my time denying effects that are obvious and repeatable just because the explanation hasn't been found yet.

[Rufus McDufus]

OK, I tried some various torques and copied some here. The sound differences are surprisingly dramatic.
I've settled on the following all in Nm:

KK
Boards (top and bottom including risers) 0.95
Ground bolt 2
Chassis back 0.8
Case bottom cover 0.8
PSU cover 0.4

KDS
Main board inc divider 0.95
PSU board 0.95
Chassis back 0.8
Case bottom cover 0.8
There are no psu cover screws (loose plastic cover)

As I say, the difference in sound quality is very noticeable. Initial observations are it's really tightened up the sound and detail is something else. It never fails to amaze me what a difference things like this make ...

[Rufus McDufus]

Been fiddling again and revised my previous settings. I'm finding I prefer the circuit boards with my torquedriver at 0.9Nm.
I haven't really tried too many earth bolt settings. I'm sticking with ThomasOK's suggestion back in this thread of 2.0Nm - I'm too chicken to go any higher than that!

KDS/1
Main board inc divider 0.9Nm
PSU board 0.9Nm
Earth bolt 2.0Nm
Chassis back 0.8Nm
Case bottom cover 0.8Nm
There are no PSU cover screws (loose plastic cover)

[Rufus McDufus]

Apologies, I'm talking to myself on this thread. I've been testing settings with the earth bolt on both the KDS/1 & KK/2 and it's quite interesting.
I've been using a setting of 2Nm on both but I've realised today that this seems to lead to great inconsistency in quality of sound on the KDS. I've tested using the higher settings and I'm finding about 3.4Nm (the highest my torquedriver goes actually) seems to sound the best - but crucially it's consistent too! This torque setting has a dramatic effect on the well-being of the KDS as well as the musicality.
It sounds really bad when this is set wrong.

OK, so I thought I'll apply this knowledge to the KK and tried a higher torque setting. The strange thing is this kills the KK quality! I've found myself reverting back to 2Nm for the time being.

The fastenings are slightly different between them - my KDS has bolt/earth connector/silver tootehd washer/case, but the KK has a black washer in place of silver. could make a difference.

[lejonklou]

Hi Rufus!

I find your reports interesting and am certain the toothed/black washer can affect the optimal torque. The same has been the case on my power amps.

On Tundra Mono and Tundra 1.2, I started using a new ground tag due to it sounding better than the previous version. It also turned out that each combination of tag and washer below it had its own optimal torque. The older combination sounded best at slightly above 0.8 Nm and the latest one at 2.0 Nm.

[Rufus McDufus]

I missed a word above - it's a black-toothed washer on the KK. I guess the conductivity would be quite different to the silver one? The connector tag on the KDS to the Dynamik may be a different material to the KK too.

I'm actually astounded how critical this one connection is! Particularly on the KDS.

[Nicolav]

Apologies, I'm talking to myself on this thread. I've been testing settings with the earth bolt on both the KDS/1 & KK/2 and it's quite interesting.
I've been using a setting of 2Nm on both but I've realised today that this seems to lead to great inconsistency in quality of sound on the KDS. I've tested using the higher settings and I'm finding about 3.4Nm (the highest my torquedriver goes actually) seems to sound the best - but crucially it's consistent too! This torque setting has a dramatic effect on the well-being of the KDS as well as the musicality.
It sounds really bad when this is set wrong.

OK, so I thought I'll apply this knowledge to the KK and tried a higher torque setting. The strange thing is this kills the KK quality! I've found myself reverting back to 2Nm for the time being.

The fastenings are slightly different between them - my KDS has bolt/earth connector/silver tootehd washer/case, but the KK has a black washer in place of silver. could make a difference.

Hi Rufus, be careful because this inconsistency is tipical after you just set the torque. you have to wait a few hours (usually 24 or more hours) before the result become stable. Otherwise you run the risk of continually change the value without finding the optimal value of torque.

[Rufus McDufus]

Absolutely Nicolav! I'm taking about a day with each setting. I lived with the low torqued earth nut for many months.

I'll tell you the story behind all this. It never sounded right from new. It used to get pretty hot too. I tried torquing bolts and it sounded better but was very inconsistent. Sounded fantastic some days, sounded terrible others. I don't think I damaged it as I was disappointed when I first got it and I went very easy on the board torques as I know how fragile the boards are, particularly from crushing.

I sent it back to Linn recently to get checked out and they actually replaced the main board & psu! It sounded brilliant when it came back.

And then of course the urge to fiddle worms its way in my head again (!) and I tried the original torques I mentioned. It sounded horrible. I thought I'd ruined it.

After this testing I realise most of it hinges on the torque of that earth bolt. You mention above everything under 3Nm affects the musicality. What I found with a low torque (2Nm) is that it makes it really susceptible to noise on the mains circuit, particularly from other devices. I switched it to a separate mains spur - noise problem gone.
Torque that bolt >3Nm and put it on the shared circuit again - mains noise problems gone. So in my case I think I'm finding it's critical for proper earthing of the product for that bolt to be tight. It may be a poorer quality conductor that needs it to be tight?

My findings in general with the KDS with it on a shared circuit (shared with the KK & Tundra Monos) are:

Board torque 0.95 - 1.0 - sounds harsh
Board torque 0.90 - sounds good

Earth nut 3.4Nm - it sounds like it's on acid. Everything is pushed forward. I find this a little too much.
Earth nut 3.2Nm - it's a little more washed out but more musical. I'm running with this at the moment. It's very close to the Linn settings actually in terms of overall sound & musicality.

I think a further improvement can be gained by isolating the DS mains-wise from the other components but I'm testing it on the same circuit for the time being as I want to make sure it is actually earthing properly.

It's complicated. Do Linn torque precisely? They must use ballpark figures as it dramatically affects the sound quality.

[Rufus McDufus]

Quick update. I'm very close now to my ideal settings.

First off on the Klimax Kontrol I've been trying higher torques on the earth bolt and it sounds initially impressive but is ultimately fatiguing. I've returned back to 2.0Nm.

KDS - earth torque makes an enormous difference to the sound. I'm not talking small 'audiophile' differences here - it can fundamentally change the character of the DS. Anything above 3 is impressive. The dynamics increase as the torque gets higher - bass extension deeper in particular - but it's difficult to live with. I find myself constantly adjusting volume to compensate during quiet or loud parts. I'm running 2.8Nm at the moment but I think the ideal is somewhere in the range 2.8-3.0.

Board torques - I find it difficult on the KK but it's more obvious on the KDS. 0.95 is the point at which the sound starts to change dramatically and gets harsher above this. I worry that this is the point at which the board is getting crushed too much due to the way the sound changes. I've relaxed it to 0.9. I tried some lower values down to 0.6 but it starts to break down at this point.
Because I find it hard to spot the difference so much with board torque on the KK I've replicated the same 0.9Nm as on the KDS.

These settings are more subtle than the higher earth-bolt torques but easier to live with and less fatiguing. It's a small improvement on the Linn settings I think. I still feel the earth bolt on the KDS must be slightly higher than the Linn setting even at 2.8Nm.


[edit] I'm happy - my final torques:
KDS boards 0.9Nm, earth bolt 2.9Nm
KK boards 0.9Nm, earth bolt 2.0Nm
Case etc. as earlier

[fieldmice]

Hello Rufus and All,

Just wonder if I can use the KDS torque setting on my KRDS/0 ?

As per Rufus's setting:
KDS boards 0.9Nm, earth bolt 2.9Nm

Thanks and have a nice day.
Kam..

Quick update. I'm very close now to my ideal settings.

First off on the Klimax Kontrol I've been trying higher torques on the earth bolt and it sounds initially impressive but is ultimately fatiguing. I've returned back to 2.0Nm.

KDS - earth torque makes an enormous difference to the sound. I'm not talking small 'audiophile' differences here - it can fundamentally change the character of the DS. Anything above 3 is impressive. The dynamics increase as the torque gets higher - bass extension deeper in particular - but it's difficult to live with. I find myself constantly adjusting volume to compensate during quiet or loud parts. I'm running 2.8Nm at the moment but I think the ideal is somewhere in the range 2.8-3.0.

Board torques - I find it difficult on the KK but it's more obvious on the KDS. 0.95 is the point at which the sound starts to change dramatically and gets harsher above this. I worry that this is the point at which the board is getting crushed too much due to the way the sound changes. I've relaxed it to 0.9. I tried some lower values down to 0.6 but it starts to break down at this point.
Because I find it hard to spot the difference so much with board torque on the KK I've replicated the same 0.9Nm as on the KDS.

These settings are more subtle than the higher earth-bolt torques but easier to live with and less fatiguing. It's a small improvement on the Linn settings I think. I still feel the earth bolt on the KDS must be slightly higher than the Linn setting even at 2.8Nm.


[edit] I'm happy - my final torques:
KDS boards 0.9Nm, earth bolt 2.9Nm
KK boards 0.9Nm, earth bolt 2.0Nm
Case etc. as earlier

[ThomasOK]

I thought I should note that on Paolo's strong suggestion Fredrik and I tried the higher torque on the ground tags on Sagatun and Tundra units. His recommended torque was 3.4Nm -2 notches. As mentioned further above Fredrik and I had tried these higher torques and had preferred the 2.0Nm setting on the Klimax units. But we decided to try them again on the Lejonklou units. What we found was surprising. The grounds do sound better on the higher torques but the exact torque for musical performance is quite precise - get it off a notch either way and it isn't nearly as enjoyable. Remember that each notch on the CAL 36/4 is about 1.5 hundredths of a Nm and you get an idea of how touchy this is. Interestingly Fredrik and I both found that on our drivers the optimum was 3.4Nm -3 notches. This one notch difference is not surprising as the drivers are only guaranteed accurate to 6% which is a bigger difference than that. And the precision necessary, which we weren't expecting, explains why we weren't happy with the setting before this.

Since this is the same torque value Paolo found for the Klimax DS and KK ground bolt I would expect that experimenting in this area would likely bear fruit. It should also be noted that while it immediately sounds more tuneful and better paced, it can sometimes be a bit tizzy when first tightened. This will settle down in a couple of days and then everything is just better.

Has anybody found if the same range of torques also works on the Klimax Radikal?

[Erik]

Hello Rufus and All,

Just wonder if I can use the KDS torque setting on my KRDS/0 ?

As per Rufus's setting:
KDS boards 0.9Nm, earth bolt 2.9Nm

Thanks and have a nice day.
Kam..

I say no. A couple of years ago when I upgraded the KDS/O to /1 I tired out the torque for the board on the Renew and surprisingly found it best around 0.6Nm. I can't recall the exact value as I sold it short after receiving it.

/Erik

[kallesprätt]

Hello!

I wonder if anybody has found the best torque to go with a KRDS/1.

/Kallesprätt

[donuk]

As a brief aside, if the OP does not mind:
Where in the UK can one buy a suitable torque wrench that does not cost hundreds of pounds?
donuk overcast downtown York