The importance of a level turntable, we should take notice.

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gregor
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The importance of a level turntable, we should take notice.

Post by gregor » 07 Jan 2018 10:40

Never been that happy with my RP3, always thought one channel was louder than the other, fretted about alignment, bias etc and I thought I had my table level, how wrong I was, equipment rack was well out, I couldn't believe it, checked the table with a bubble level and a spirit level, it was all over the place, so off with the turntable but left the amp on to weigh it down, got the rack level in all plane's, placed the table on the rack but was just a smidgen out, put a couple of playing cards on the back foot, perfect, played a couple of records I had on from yesterday, Ray Fenwick's Keep America Beautiful Get a haircut and 10cc Sheet Music, what a difference, now sitting here with a huge grin on my face, advice given here is always very good but I must admit I should have taken more advice on turntable levelling and how important it is, check your tables and see if there out, you might be surprised.

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Re: The importance of a level turntable, we should take noti

Post by jackie » 07 Jan 2018 12:41

Agree totally.

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Re: The importance of a level turntable, we should take noti

Post by wolfie62 » 07 Jan 2018 14:16

Having the TT level is a prerequisite to everything else.

When I check for leveling, I test using a bubble level on all areas of the platter, in all directions. Then I check the level of the plinth in the same way. Finally, with no power on the TT, I balance the tonearm to neutral. Then I gently swing it incrementally from rest all the way to the spindle, to check that the tonearm stops and doesn't move wherever I put it. Just gentle nudges from rest all the way to the spindle. From here, I know that my turntable is completely neutral and level, with no effect on tonearm movement.

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Re: The importance of a level turntable, we should take noti

Post by Doug G. » 09 Jan 2018 21:38

A level turntable/platter is only necessary with a statically balanced table. It is not critical with a dynamically balanced table.

Doug

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Re: The importance of a level turntable, we should take noti

Post by Facelift3 » 09 Jan 2018 21:46

Doug G. wrote:A level turntable/platter is only necessary with a statically balanced table. It is not critical with a dynamically balanced table.

Doug
Doug, This sounds interesting, please explain the difference between statically and dynamically balanced tables.

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Re: The importance of a level turntable, we should take noti

Post by Doug G. » 09 Jan 2018 22:03

A statically balanced table has the arm balanced with a counterweight and the tracking force is then added by moving the counterweight forward. The levelness of the table is very important so the downforce is straight down toward the base/plinth.

A dynamically balanced table has the arm balanced with a counterweight and the tracking force is added using a spring. It doesn't matter if the table is level because the spring always pulls the arm straight toward the base/plinth no matter the angle. In fact, a dynamically balanced table can play upside down.

Doug.

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Re: The importance of a level turntable, we should take noti

Post by JDJX » 09 Jan 2018 22:08

Facelift3 wrote:
Doug G. wrote:A level turntable/platter is only necessary with a statically balanced table. It is not critical with a dynamically balanced table.

Doug
Doug, This sounds interesting, please explain the difference between statically and dynamically balanced tables.


Yeah I would like to know also and have no idea what he means in regards to dynamic vs static balance.

In general terms ....
"In general, dynamic means energetic, capable of action and/or change, or forceful, while static means stationary or fixed."

Trio KD1033
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Re: The importance of a level turntable, we should take noti

Post by Trio KD1033 » 09 Jan 2018 22:15

I don't know all the details, but I think it's something to do with the arm being balanced both vertically and laterally on it's bearings. My SME 3009 series 2 improved is just such an arm. If you balance the arm to float just above the platter surface, you can tip the turntable back as far as you dare and it won't move, but gently breathe on it, and it smoothly rotates. Have a look here at this link from this very site:

https://www.vinylengine.com/library/sme/3009.shtml

You'll see there that up to thirty degrees tilt is mentioned before any ill effects! Don't think I'd be that slap-dash, but it's quite interesting isn't it?

Andy

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Re: The importance of a level turntable, we should take noti

Post by wolfie62 » 09 Jan 2018 22:22

Well, I would beg to differ that a dynamically balanced tonearm doesn't need a level plinth.

While a spring or electronic servo may provide accurate VTF, it WILL NOT offset the tonearm that wants to swing toward rest or toward the spindle because the entire turntable is not level.

The turntable that is not level will also have inaccurate anti-skate, since the tonearm has added force moving it sideways, either toward the spindle or away from the spindle.

My Denon DP45F is an example of a dynamically balanced tonearm. The counterweight is adjusted for neutral weight; the servo circuits add the VTF and antiskate as dialed in by the potentiometers on the plinth. It also has servos that control side to side motion. But none of those circuits are any good if the turntable is not level; you will still have a tonearm that has added forces either toward the spindle or away from it.

So, the idea that a dynamically balanced tonearm neutralizes all forces on the tonearm is pure fantasy. The only TTs that can play properly upside down or sideways are linear trackers. At least as far as I have seen.

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Re: The importance of a level turntable, we should take noti

Post by Trio KD1033 » 09 Jan 2018 22:31

I remember Dual claiming that their decks would theoretically play upside down. Take a look at this video, not upside down, but wow!

https://youtu.be/x5BWzlxP-80

Andy

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Re: The importance of a level turntable, we should take noti

Post by scrapjack+ » 10 Jan 2018 01:57

This article claims statically balanced tone arms can be adversely affected by warped records. It also provides a diagram of one example of dynamically balanced tone arms.
http://www.soundfountain.com/amb/tonearm.html

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Re: The importance of a level turntable, we should take noti

Post by Facelift3 » 10 Jan 2018 05:53

My thorens is quite difficult to level, I have to

1 level the shelf it is on
2 level the plinth
3 level the platter

and after everything is absolutely level the platter looks like it isnt level to the naked eye

scrapjack+
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Re: The importance of a level turntable, we should take noti

Post by scrapjack+ » 10 Jan 2018 05:56

Facelift3 wrote:My thorens is quite difficult to level, I have to

1 level the shelf it is on
2 level the plinth
3 level the platter

and after everything is absolutely level the platter looks like it isnt level to the naked eye
It could be that the tone arm isn't level, some records are thicker or thinner, also if the mat has been changed.

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Re: The importance of a level turntable, we should take noti

Post by Facelift3 » 10 Jan 2018 07:24

scrapjack+ wrote:
Facelift3 wrote:My thorens is quite difficult to level, I have to

1 level the shelf it is on
2 level the plinth
3 level the platter

and after everything is absolutely level the platter looks like it isnt level to the naked eye
It could be that the tone arm isn't level, some records are thicker or thinner, also if the mat has been changed.
This is true, the grace 747 thats on it atm is very very slightly bowed downwards on the last third of the arm (headshell end) its a nightmare to get correct cantilever angle).

I reckon the previous owner must have dropped something on it or something.

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Re: The importance of a level turntable, we should take noti

Post by Facelift3 » 10 Jan 2018 07:25

wolfie62 wrote:Having the TT level is a prerequisite to everything else.

When I check for leveling, I test using a bubble level on all areas of the platter, in all directions. Then I check the level of the plinth in the same way. Finally, with no power on the TT, I balance the tonearm to neutral. Then I gently swing it incrementally from rest all the way to the spindle, to check that the tonearm stops and doesn't move wherever I put it. Just gentle nudges from rest all the way to the spindle. From here, I know that my turntable is completely neutral and level, with no effect on tonearm movement.
Why do you adjust the platter level THEN the plinth?

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