LP12

[Geoff.R.G]

I'm gonna have to change my signature at the bottom of my posts. These LP12 experiments were certainly not inspired by the Doc. He would have told me to burn it

I think he'd say that if you like it then that's all that matters. He'd certainly approve of doing away with the springs.

I read about a guy in Sweden selling 'magic mushrooms' to replace the LP12 springs, and they are being lapped up even by Linn fanboys. Maybe they are hallucinogenic, as well as being a more logical and effective engineering solution...

Do you have a link for the mushrooms?

[karatestu]

I'm gonna have to change my signature at the bottom of my posts. These LP12 experiments were certainly not inspired by the Doc. He would have told me to burn it

I think he'd say that if you like it then that's all that matters. He'd certainly approve of doing away with the springs.

I read about a guy in Sweden selling 'magic mushrooms' to replace the LP12 springs, and they are being lapped up even by Linn fanboys. Maybe they are hallucinogenic, as well as being a more logical and effective engineering solution...

I have heard of these magic mushrooms, very similar to John's insoles ie hollow and squashy. There are a few who rave about them on perfect farming monthly but as usual they get shot down by the Linn fanboy attack monkeys.

None of the insoles actually touch the hanger bolts and the top is perfectly shaped to fit in the subchassis cut out's. A neat touch is the plastic nuts used for tightening. They are designed to be tightened by hand so no sockets required like with the metal nuts linn use.

Now that the deck is springless I wonder if there is any value in adding some sort of decoupling feet and using three rather than four ? I might try using the old suspension springs as feet with some heatshrink for damping.

[savvypaul]

I'm gonna have to change my signature at the bottom of my posts. These LP12 experiments were certainly not inspired by the Doc. He would have told me to burn it

I think he'd say that if you like it then that's all that matters. He'd certainly approve of doing away with the springs.

I read about a guy in Sweden selling 'magic mushrooms' to replace the LP12 springs, and they are being lapped up even by Linn fanboys. Maybe they are hallucinogenic, as well as being a more logical and effective engineering solution...

Do you have a link for the mushrooms?

https://hifihaven.org/index.php?threads ... lp12.9635/

[Geoff.R.G]

I think he'd say that if you like it then that's all that matters. He'd certainly approve of doing away with the springs.

I read about a guy in Sweden selling 'magic mushrooms' to replace the LP12 springs, and they are being lapped up even by Linn fanboys. Maybe they are hallucinogenic, as well as being a more logical and effective engineering solution...

Do you have a link for the mushrooms?

https://hifihaven.org/index.php?threads ... lp12.9635/

Thanks Paul, looks like a cheap upgrade/repair as the suspension on my TD160 is probably pretty much done after over 40 years. Might be worth a try.

[karatestu]

Thanks Paul, looks like a cheap upgrade/repair as the suspension on my TD160 is probably pretty much done after over 40 years. Might be worth a try.

Go on Geoff, you treat yourself. Life's too short and you deserve it

[karatestu]

Having read that thread at hifihaven I think putting decoupling feet on the old fruitbox may not be the way to go. But then it might. Only I can decide after trying.

That thread also gives me confidence in my decision to not clamp the arm cable in a p clip. That must serve as a short circuit for vibrational energy to go straight to the tonearm ??

[Geoff.R.G]

Thanks Paul, looks like a cheap upgrade/repair as the suspension on my TD160 is probably pretty much done after over 40 years. Might be worth a try.

Go on Geoff, you treat yourself. Life's too short and you deserve it

Money isn't the issue Stu, time is however. May be in the spring.

[karatestu]

My brain has been on steroids since playing about with this TT. What if i do this, what would happen if I did that ? Thinking of ways to improve the sound without spending money and modifications that can easily be removed without a trace.

I have had much success with sand in my diy speakers. I attached a 60mm diameter length of solid brass round bar to the back of the drivers magnet and sunk it into as much sand as I could in the bottom of the spherical enclosure. Don't try this with point and squirt, I don't see how it could be done. It seems to dissipate most of the vibration.

Can this concept be transferred to a turntable? At this point in time I don't see why not. It is a very effective way of eating vibrational energy. It seems to me that the main objectives of a good turntable are to stop vibrational feedback getting to the stylus, keep the three elements of arm base, motor and bearing in a rigid manner as regards each other and keep the speed stable ( and not fast like some Rega's).

Keeping the arm base, motor and bearing in a rigid relationship is completely at odds with preventing vibration getting to the stylus. Forgive me if I state the obvious. Linn try to isolate the vibration from the stylus by the use of a subchassis with armboard and bearing on it hung via three springs with the noisy motor being on the top plate. This famously fecks up the speed stability. Pink Triangle put the motor on the same structure as the bearing and arm base with much success but they used a low vibration DC motor. I have to make do with an AC one.

So how about this for an idea. A rigid box (plinth) with solid bottom that sand can be put in. Make a one piece rigid top plate which has arm, bearing and motor attached. These three elements have a rigid relationship to each other. This top plate is sunk into the sand and played about with until level. It does not touch the plinth at any point and everything on the underside is in contact with sand.

So we have good speed stability and vibration is eaten up and turned to heat by the sand. There might be something i have not thought about. It might be a pig to get level and stay there. It might sound completely shite but then again it might sound completely awesome.

[Geoff.R.G]

Stu, I am not sure how having the motor isolated from the bearing and arm board is affecting the speed unless there is considerable movement between the two. With your stiffer suspension that shouldn't be the case, Linn didn't invent the suspended chassis and belt drive arrangement, the TD150 was using it in 1965, 8 years before the LP12, without any apparent speed problems (none reported that I recall). Speed fluctuations are more likely to be motor induced than as a result of the suspension, as you have it. Obviously if the chassis twists there will be speed fluctuations.

I am also fascinated by Richard's comment that "Belts are for trousers". This completely ignores the fact that for years belt drives were perfectly acceptable in tape machines where one might expect exactly the same problems as are, apparently, encountered with turntables, except that they would be magnified as they affect recording and playback differently.

I have already summarised the pros and cons of the different turntable drive systems, none is perfect.

[karatestu]

Stu, I am not sure how having the motor isolated from the bearing and arm board is affecting the speed unless there is considerable movement between the two. With your stiffer suspension that shouldn't be the case, Linn didn't invent the suspended chassis and belt drive arrangement, the TD150 was using it in 1965, 8 years before the LP12, without any apparent speed problems (none reported that I recall). Speed fluctuations are more likely to be motor induced than as a result of the suspension, as you have it. Obviously if the chassis twists there will be speed fluctuations.

I am also fascinated by Richard's comment that "Belts are for trousers". This completely ignores the fact that for years belt drives were perfectly acceptable in tape machines where one might expect exactly the same problems as are, apparently, encountered with turntables, except that they would be magnified as they affect recording and playback differently.

I have already summarised the pros and cons of the different turntable drive systems, none is perfect.

Good points Geoff. Not having springs anymore means I will not have to suffer with the motor and belt making the subchassis move sideways.

People say that noisy ac motors can produce vibrations which can if you are not careful make their way to the stylus. That would be one good reason to isolate the motor if it really is that bad.

Speed fluctuations due to the power supply is also a concern. My lingo1 probably would benefit from the electrolytic caps being replaced, it is after all 35 years old. The Avondale Audio Taps2 psu (which I haven't tried yet) works on a very different principle- more like the Naim Armaggedon and Norton psu's.

Belts are for trousers Direct drive is seen as better for speed but it probably isn't as good with regards to isolating motor noise.

Geoff, what do you think to my idea with the sand ? Batshit crazy?