Marble Turntable Sub-base - Suggestions?

[rob g]

Originally Posted by nigel pearson

Squash balls work well . Loricraft use them on the Garrard 501 and openly admit it . 5 are used . Worth a try . I have used big bubble wrap .

Me too, I use squashballs with my 401 plinth.
That said proper isolation on a wall mounted shelf makes the real difference.

Rega's are much better with rigid mounting.
Soft bouncing suspension systems within turntable plinths (LP12, systemdeck, Pink Triangle) are actually designed to simply isolate internal vibrations from the motor, stop these getting to the arm. Suspended decks are actually far worse for external ones. If you have only used a turntable in a room with a concrete floor you won't have experienced this difference between suspended and non suspended.
With any of these suspended decks on a surface attached to the floor you have to be careful how you walk past the deck (I have experienced this with all of the decks I mention above, not tried Xerxes in that room).

With the Rega or the Garrard 401 attached to a shelf mounted on a brick wall I could happily jump up and down (probably go through the floor!) and not even the slightest hint of a wobble on the deck. I appreciate not everyone has this option.

[rob g]

I have experimented with the rubber inner tube method with a Planar 3, actually I think I used this for a couple of years. Worth a try, not a big difference but dirt cheap.
Then the question becomes one of inflation. What is the appropriate amount of air in the tube.

[nigel pearson]

Linn used to say low mass and ridged . I think that is correct . I use 401 and Naim Aro . Lyra Helikon ( on loan and I miss it ) . If you have heavy piece of furniture and two Linn LP12's try this . If you bounce one the other one starts up in resonance . Big movements I should tell you . That must mean something . Using LP12 right now myself . Love the 401 more .

[Nanook]

Originally Posted by nigel pearson

On the strength of this the prof bought a B&O turntable . I didn't get that !

Some people make magnetic levitation tables . Looks easy to do and might work ( lots of small magnets ) . Will need stabilizing if so ( rubber bands ) .

Nigel et al,

First I am not sure which B&O table the prof bought but if the "old school" types were still around, many earlier B&O tables were actually re-badged Thorens tables. The Beogram 3000 (IIRC) was essentially a TD124.The Beogram 2000 was a more modern interpretation still with a belt and idler drive. Some of their tables were Lencos, as well (at least they sure look like 'em). None were too bad regarding isolation. Pretty sure the prof did some analysis of tables before settling for one.

Unsure about any mag levitation tables. Anything that can levitate a suitable mass may interfere with the electric performance (both signal and power).

[rob g]

Originally Posted by nigel pearson

Linn used to say low mass and ridged . I think that is correct . I use 401 and Naim Aro . Lyra Helikon ( on loan and I miss it ) . If you have heavy piece of furniture and two Linn LP12's try this . If you bounce one the other one starts up in resonance . Big movements I should tell you . That must mean something . Using LP12 right now myself . Love the 401 more .

I have used both, my Dad has used an LP12 for a long time, it still sounds great when I hear it. I prefer the Garrard on a lot of material, they both have their strengths. LP12 is full and fruity, it's musical for want of a better word, despite being more obviously coloured they just work. Price for new ones is a bit bonkers. Generally I hate the word musical, like an Audiophile get out of jail free.

In the UK Linn users often used an Ikea Lack table.
LACK Side table - birch effect - IKEA

[nigel pearson]

The B&O was the parallel tracker . Lets be honest it was about the worlds best for isolation . MMC 20 pick up with sapphire cantilever . In my opinion a TD 160 would have been an excellent choice .

LP12 is moderately good on feedback .

TD 124 .Now you are talking . I understand Loricaft have some they want flog cheapish ( now idea how cheap ) .

One of the best of that time was called Empire Troubadour .

[jkorten]

2 or 3" thick maple chopping block. Mount it on 4 vibration isolation pads or 3"x3"x1" felt blocks. You want to drain vibration from the turntable, but early posters are correct about ringing in stone/granite/marble. The wood has a nice deadening quality yet has the mass.

[rob g]

Originally Posted by Nanook

Nigel et al,
Unsure about any mag levitation tables. Anything that can levitate a suitable mass may interfere with the electric performance (both signal and power).

Also it will not truly isolate the deck as the magnetic shelf would be attached to the surface that would transfer energy. A slight cushion at best.

Isolation is a difficult game, even for top grade engineers:
London Millenium Bridge Opening - YouTube

Project make a high mass deck with opposing magnets under and in the platter. Allegedly it puts less pressure on the bearings.
Pro-Ject RM10.1 Turntable

[vinylkid58]

Originally Posted by rob g

Price for new ones is a bit bonkers.

I think it's beyond bonkers.

Originally Posted by rob g

In the UK Linn users often used an Ikea Lack table.

Mine's on the fireplace hearth. The only think that's going to upset it is an earthquake.

jeff

[nigel pearson]

Must go to bed soon . This is fascinating . The first mag-lev was perhaps the Platine Verdier ( and ADC ? ) . I love that turntable .

Linn had what was called the closed loop principle . The sound would go down the arm and return through the bearing in a closed loop . They would say mag-lev no good .

If you put screwdriver handle to the bone of your ear and the blade to the arm base ( easy on a Rega , not a LP12 ) you can hear the music . Surprisingly ,very distorted . Some decks not so . Those sound good I find . A Dual not good ( no critism intended as Dual are very reasonable ) .

The cheap Project is great value . I don't know the others . .

I knew someone ( Graham Old ) who tried mag lev on a Garrard 401 I think and said no good . I know the magnets if interested .