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Tonearm “rigidity”: beliefs, myths and revisionism

i use a tonearm board that adopts constrained layer damping construction,it also only touches the tt plinth by 3 tiny contact points. it has bettered one of panzerholz and any others i have used in the past.
 
I bought a crazy expensive Swissonor panzerholz armboard (thankfully second hand for not much money) for the 124 that is actually decoupled from the 124 chassis by rubber grommets. I didn’t get on with it at all. It just robbed the deck of the dynamics and groove one buys an idler deck for in the first place. I don’t know if I did anything wrong in setting it up, but it really didn’t work to my ears. The standard board (mine is a Schopper, but it’s just a wood board like the Thorens original) bolted on finger-tight just kills it to my ears. So much more life and groove. Annoyingly the panzerholz board is of such a design I couldn’t try it without the rubber decoupling without modifying it, and I’d prefer just to sell it at some point.

PS Not doing a great job advertising this one!
 
Setting up a record play is full of compromises. Obsessing about one aspect of setup can at times get in the way of finding the best set up. Eg worrying too much about azimuth when the cartridge / arm interface needs attention. I sometimes feel it's like balancing several spinning plates. In the end optimising every aspect is important but working out what's important for your cartridge, arm and deck isn't always the straightforward and requires experimentation. It's all part of the fun with vinyl.
 
There’s folks on the Lejonklou forum, including a US Linn dealer, who have been testing torque settings on hi-fi components for years. They have torque settings for building LP12’s, various speaker drivers, etc.. I embraced their research and have had my LP12 and speaker drivers setup with a torque screwdriver since 2012. Nothing new here, doing it by feel doesn’t work.
 
jamie123 said:
i use a tonearm board that adopts constrained layer damping construction,it also only touches the tt plinth by 3 tiny contact points. it has bettered one of panzerholz and any others i have used in the past.
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What’s it made of?
 
John said:
I embraced their research and have had my LP12 and speaker drivers setup with a torque screwdriver since 2012. Nothing new here, doing it by feel doesn’t work.
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Their “research” will only be ‘doing it by feel’ and then measuring their preferred setting. Fine if you are part of a flock, but if you are doing your own thing with combinations of kit no one else is using then you do actually have to think for yourself now and again! I’d also argue a Linn dealer will likely be highly tuned into the Linn house sound, which is a very distinct thing that not everyone wants by any means.
 
Tony L said:
Their “research” will only be ‘doing it by feel’ and then measuring their preferred setting. Fine if you are part of a flock, but if you are doing your own thing with combinations of kit no one else is using then you do actually have to think for yourself now and again! I’d also argue a Linn dealer will likely be highly tuned into the Linn house sound, which is a very distinct thing that not everyone wants by any means.
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No way are they doing any of their research by feel, all their fastening is done using a specific torque screwdriver. There’s no way the preciseness can be done by feel!
 
Tony L said:
It has been known for a very long while that the old Rega Planar 2 and 3 sound better with the big arm base nut just gently nipped-up to the point you can still use the cueing arm without the armbase moving, but no more than that. I strongly recommend trying that if you have one of these decks, or a deck with an RB250-300. Just tight enough so you can still use the cueing arm!
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100% agree with this - I was amazed when I took the advice of the nice man from Origin Live and tried this. Unquestionably the best tightness was only just tight enough to stop the Rega arm wobbling about.

You can certainly over-tighten Linn arms too, and the sound changes in a distinct way. When it's too tight the sound starts to feel fussy and lacking in energy. But my recollection is that Linn advice is moderately tight cartridge bolts and just comfortable arm pillar.
 
I went overboard a few times with overtightening turntable setups. I managed to crack the arm pillar on my first Ittok by overtightening the grub screw. I drove the screws holding the Syring PU2 mass-ring into the housing of the arm. I managed to deform the zinc-alloy body of a brand new Koetsu cartridge. And that is just the start too.

While I was waiting to get a replacement Koetsu, I reverted back to the Linn Karma in the Zeta. It was disappointing compared to the Koetsu....bass was lumpy and not extended and the crispness and drive at the top end was flat. I then gave a relatively cheap 'mod' a go....the Cartridge Tip Toes, from the Mod Squad. It was mainly a shim with three bumps that interfaced the undersurface of the headshell to the cartridge body below, giving it point contact rather than that of a broad surface. This transformed the Karma and it then sounded every bit as good as the Koetsu.

BTW, I experimented removing the arm clip from the Zeta. It turns out it was ringing and causing a lot of coloration to the midrange. I told my local dealer about that, and he started removing the clips from his Zeta's too, having coined the term of the Tuning Fork to describe the arm clip, as it really degraded the sound to quite a surprising degree. I also found that clipping the finger lift (that was an integral part of the Zeta's headshell) also improved matters, although this of course was not reversible.

The Ittok responded to a lesser degree by removing the cueing mechanism.

Record replay is 100% based on recovering encoded mechanical vibrations, so unwanted vibrations can greatly effect the end result. The thing about tight and rigid....these do not eliminate vibrations, just push them into a higher frequency with a high Q.
 
rontoolsie said:
The thing about tight and rigid....these do not eliminate vibrations, just push them into a higher frequency with a high Q.
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Absolutely, that is certainly my view. Often from out of the audio range and into it,

PS I quickly looked at the ‘Lejonklou’ Linn dealer forum John mentioned (I’d never heard of it) and the torque values they are using are tiny. The sort of values I’ve been discussing (most values a fraction of an Nm), so it looks like Linn themselves have shifted a very long way from what they were advocating back in the ‘80s. As stated I’ve personally seen more than one Linn “trained” dealers apply astonishing levels of torque to things that clearly didn’t need it. Literally allen-key bending forces! I won’t name them, but if they are reading this, yes, I saw you!
 
Tony L said:
I’ve seen dealers who have been on Linn “training” courses absolutely butcher kit. Watching one set up a friend’s LP12 back in the ‘80s was the point I started insisting on doing everything myself. I suspect the vast majority of big dents you find in the VTA adjustment on Ittoks (which can easily destroy the lateral ball races) were done by dealers. Very few people who had paid £3-400 for an arm would actually do that level of damage themselves! Same with all the ugly chewed-up headshells. I’ve watched it happen first hand! Rega and others learned from this and supply a torque wrench, which is not high-torque at all (I can’t remember the exact Nm figure, but it isn’t much at all on a Linn dealer scale!).
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Unfortunately there's no training for mechanical sympathy, I think it's just natural feel. Someone who sells and sets up Hi-Fi probably isn't naturally predisposed to knowing how much is too much.

Back to the subject, I tighten up cart screws to the point where you can still make alignment adjustments with slightly firm movement of the cart body with fingers, but tight enough that it stays where you put it. I'm not old enough to have been around during the whole 'Linn Tight' thing, so it is just something I've learned about through forums, but all my mechanical adjustments to kit have been done through common sense and a bit of mechanical sympathy.
 
matt j said:
Unfortunately there's no training for mechanical sympathy, I think it's just natural feel.
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Agreed, it’s something I’ve always instinctively ‘got’. I was that highly annoying type of kid where as soon as my parents went out I’d dismantle their stuff to see how it worked (phone, radios, food mixer etc). Luckily I could always put it back together again before they got back home! I can’t remember ever getting caught. I electrocuted myself a couple of times though, as you do.

It would be interesting to get hold of a low-value torque wrench to better articulate the settings I’m finding work. I obviously have one for my bikes (I assemble my own), but that uses far higher torque settings (5N m upwards depending on the part), so is of no use here as the lowest it can measure is 3N m.
 
All interesting. It is worth bearing in mind that in some rooms temperature changes throughout the day and year, and depending on the precise nature of the bolted connections, the tightness can vary significantly and even work loose. In fact, with Rega arms it is pretty much guaranteed that it will work loose from optimal tightness, just from the repetitive process of cuing.

The only way to live with this is common sense maintenance.

I don't use a Rega arm any more, so I usually tighten to a tightness which I imagine will not work loose, and call that good.
 
Re: Torque settings found on the Lejonklou forum: I'm not sure that's a Linn adoption as such (though it might be) but more a practice that seems to have been adopted by that forum in particular. The one Torque value Linn have started to be very specific about is the new bearing to sub-chassis fastening Torque, which is 3.5nm. That's not a lot for a 16mm thread / nut (imagine 2x1KG bags of sugar hanging off a 20cm spanner) It's not clear yet whether the lightness of that torque is because Linn believe it's acoustically better or to prevent damage to the sub-chassis surface (which has happened from dealers fitting the new bearing apparently) or to ensure it can still be undone in 10 years time.

I must admit, I'm not clear on the affect on vibration of different torques on fasteners...Assuming that you want the bearing and sub-chassis to behave as one piece, once the fastening is tight enough to prevent any movement, is there any benefit from applying additional tightness? Does doing it up as tight as possible apply additional stress to the outer surfaces, changing the way the object transmits vibration? Several posters on that forum seem to prefer a lower torque than Linn's specified 3.5nm for the bearing nut.

Certainly the recommendation for the Aro arm pillar grub screw is: "just nipped up" and definitely not tight. Is that connection partially lossy, then? If so, that would seem to break the "closed loop" idea. It's an interesting area, particularly thinking about cartridge bolts.
 
Every cart, arm, deck combo will be different. No doubt adjusting fitment tightness affects the sound but the results will be different with every setup.

Tightening torque is only a measure of the strain on the bolt, it doesn't really tell you how tight it is pulling the faces together. The difference between 10nm on a greased and ungreased bolt is huge never mind mild steel or stainless.

Just accept its a crap shoot and stop when you get a sound you prefer. Or do it right and measure the effect on the signal
 
Tony L said:
I like the classic aesthetic of the arm with its shell too much to use a “better” one, but it would be interesting to try at some point with felt decoupling and I’m certainly curious to know if many have experimented with these type of isolation products, especially if you are using them with 1980s “rigid” tonearms (Linn, Rega, Mission, Zeta etc), i.e. effectively kicking that whole ‘closed loop’ ideology into the weeds!
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The closed loop principal isn't really an ideology, more a basic fact of record player design and has been since the invention of the format. The principal always has involved compromises due to the nature of the materials and limits in understanding.

The LP12, which supposedly exemplifies closed loop, used a lossy wooden armboard attached to the subchassis with three tiny wood screws. Bolting through the armboard, a mod promoted by some at the time, threw off the tonal balance of the deck and made it sound worse. The Rega RB300 used a stainless steel arm pillar bolted through the plinth. Rega later adopted plastic feet screwed only from above with wood screws. Clearly less ridged than the earlier arrangement but better sounding.

Both Linn and Rega employ more ridged construction on their better turntables but it's likely improvements in other areas allow this to balance out. The point being that 'closed loop' is not a myth. All turntables are like that, they only differ in how energy transfer is managed. Our perception of whether materials employed are hard or soft is largely irrelevant. All that matters is how they behave at the resonant frequencies concerned and how that impacts energy management within the system as a whole.
 
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