Where to Place Digital Gauge on Platter?

[AnzacSonata]

When using one of those battery-powered digital tracking force scales, is there a certain place on the platter/mat wherein the scale should be optimally placed? I'm not talking about using a mat or placing the gauge on the bare platter beneath it (which has been debated before; I always use mine by leaving the felt mat on, as it seems to approximate the height and position of a record on the platter when I place the stylus onto the sensing pad) -- I mean where the arm should be positioned when lowered onto the scale...

If I place the scale in different places on the mat and drop the arm, I tend to get different readings (on an AT-LP120) in terms of tracking force on the scale -- is there a certain place the scale should go on the mat every time to ensure accuracy? Should it be placed towards the outer edge of the platter (near where the lead-in grooves of the LP would be) or should it be more towards the inner spindle?

Further, if I have been experiencing IGD and this may perhaps be chalked up to tracking force (don't think so, because I'm currently running a pretty high 2.35 grams on an AT95E and still get distortion on all inner tracks -- I know, I know, it could be alignment...but that's for another time), should I put the scale more towards the spindle to measure force at that position?

 

[Poinzy]

I just place the scale where it's easiest to read, close to the edge of the platter.

 

[AnzacSonata]

I just place the scale where it's easiest to read, close to the edge of the platter.

Does it not matter where it's placed, though? Why do I seem to get different readings across different areas of the platter?

 

[NoTransistors]

Because properly-applied anti-skate is theoretically increased as the needle gets closer to the spindle, this might be screwing with your reading. Just a wild guess.

 

[AnzacSonata]

Because properly-applied anti-skate is theoretically increased as the needle gets closer to the spindle, this might be screwing with your reading. Just a wild guess.

Can you elaborate a bit on this? So where should the gauge be ideally placed on the platter?

BTW, what part of Brooklyn you in? My parents had a furniture business for years throughout the borough; in Flatbush and Canarsie, and I still have family there in Manhattan Beach.

 

[NoTransistors]

I use a Shure balance-type gauge, which is accurate and works well, but not as sensitive to a butterfly sneezing from across the room.
Skating increases as the groove spirals toward the center. So there needs to be more and more anti-skate applied as the record plays. Who knows, this might be screwing with how firmly the needle sits on the scale's platform. Unless someone else here has a better answer. So look, a fraction of a gram will not make any difference. Make certain that the turntable is level and the scale's platform on which you place the needle is the same height of a playing record.

 

[AnzacSonata]

I use a Shure balance-type gauge, which is accurate and works well, but not as sensitive to a butterfly sneezing from across the room.
Skating increases as the groove spirals toward the center. So there needs to be more and more anti-skate applied as the record plays. Who knows, this might be screwing with how firmly the needle sits on the scale's platform. Unless someone else here has a better answer. So look, a fraction of a gram will not make any difference. Make certain that the turntable is level and the scale's platform on which you place the needle is the same height of a playing record.

I am certain the turntable is level and the scale's platform is approximating the height of a record (as I originally indicated).

I'm concerned with WHERE the gauge needs to be placed on the platter when measuring -- near the outer edge, in the middle or more towards the spindle...or if this doesn't make any difference at all (though my scale is telling me something different)...

But why would a STATIONARY platter have an affect on how the needle is sitting on the scale? I understand that the anti-skate is dynamic in that it changes as a record nears the spindle, but what does this have to do with a scale being placed on a non-moving platter and a stylus lowered onto it?

 

[NoTransistors]

Your problem has no logical causes, unless there is something magnetic under the alloy platter.

 

[tnsilver]

So where should the gauge be ideally placed on the platter?

In theory, it doesn't matter. In practice, like always, it depends. Like mentioned earlier, some anti-skate mechanisms, although should only apply lateral compensation force, also apply, in conjunction with the tonearm angle, some vertical force. This adds weight (VTF) near the center of the platter. Some scales are very sensitive to their location on an unbalanced platter, and even more so, to the exact point of contact of the stylus on the weighing plate/surface. With all of the above, the most comfortable piece of platter real-estate to situate the scale, is near the outer rim, which also allows more tonearm leverage on the weigh plate. I am actually using a butterfly sneeze sensitive scale and it won't matter where on the platter it's located. ...and yes, magnetic attraction could alter your measurements too.

 

[AnzacSonata]

In theory, it doesn't matter. In practice, like always, it depends. Like mentioned earlier, some anti-skate mechanisms, although should only apply lateral compensation force, also apply, in conjunction with the tonearm angle, some vertical force. This adds weight (VTF) near the center of the platter. Some scales are very sensitive to their location on an unbalanced platter, and even more so, to the exact point of contact of the stylus on the weighing plate/surface. With all of the above, the most comfortable piece of platter real-estate to situate the scale, is near the outer rim, which also allows more tonearm leverage on the weigh plate. I am actually using a butterfly sneeze sensitive scale and it won't matter where on the platter it's located. ...and yes, magnetic attraction could alter your measurements too.

Thanks very much Tom; so, in your opinion, setting the scale near the SPINDLE wouldn't account for a better tracking force to counter inner groove distortion (being that this is where the inner grooves would be on a record)?

 

[AnzacSonata]

Wait a minute, fellas, wait a minute...

Are you both suggesting that even to make small, minute changes in tracking force -- for example, I'm tinkering with the idea of increasing my AT95's force from 2.35 where it's currently at to 2.4 or even higher to combat nasty sibilance with this cart; the maximum recommended is 2.5 -- the ANTI-SKATE needs to be adjusted to zero? Or is Tom saying that by placing the scale near the outer edge of the platter, this is where the least amount of AS pressure would be added, so a truer tracking force reading would be achieved?

 

[AnzacSonata]

You should set your AS to 0 during the weigh-in. Position won't matter then.

If I don't touch my AS during the weighing process, is the best position for my scale to be in on the outer lip of the platter?

 

[Rockon1]

Wait a minute, fellas, wait a minute...

Are you both suggesting that even to make small, minute changes in tracking force -- for example, I'm tinkering with the idea of increasing my AT95's force from 2.35 where it's currently at to 2.4 or even higher to combat nasty sibilance with this cart; the maximum recommended is 2.5 -- the ANTI-SKATE needs to be adjusted to zero? Or is Tom saying that by placing the scale near the outer edge of the platter, this is where the least amount of AS pressure would be added, so a truer tracking force reading would be achieved?

I would set antiskate to zero . Don't want sideways force messing with trying to measure the tracking force. We are talking about fairly delicate measurements here.Bob

 

[AnzacSonata]

I would set antiskate to zero . Don't want sideways force messing with trying to measure the tracking force. Bob

Even when using a DIGITAL scale? This is the first time I'm hearing of this...

 

[Rockon1]

Even when using a DIGITAL scale? This is the first time I'm hearing of this...

Well its not that difficult to remove the antiskate from the equation so why not? It may or may not be an issue or , more specifically your issue but I would think it would be easier to get a more stable measurement without it. Bob

 

[restorer-john]

I'm tinkering with the idea of increasing my AT95's force from 2.35 where it's currently at to 2.4 or even higher

0.05grams is to going to make 1 iota of a difference.

At 2.35 grams, an extra 0.15 to take it to 2.5 might change it a touch, but you are at the top range of it already. (1.5-2.5).

Even 3.0g won't hurt it.

Absolutely zero the antiskate. Measurements will be wrong otherwise. (you have two distinct forces operating on a strain gauge designed for measuring vertical deflection only. You end up with a vertical and the vectored force of the horizontal )

 

[Rockon1]

0.05grams is to going to make 1 iota of a difference.

At 2.35 grams, an extra 0.15 to take it to 2.5 might change it a touch, but you are at the top range of it already. (1.5-2.5).

Even 3.0g won't hurt it.

Absolutely zero the antiskate. Measurements will be wrong otherwise.

I missed that part. If you are shooting for such minute changes 1)I agree with RJ- it definitely wont make a difference 2) Is your scale up to the task?

How much of a difference have you seen on different parts of the platter anyways? Bob

 

[tnsilver]

Neutralize any extrinsic influence either by measuring at the rim or by resetting the AS, or both. It's the same principal. Once again... Try a proper cart alignment. If you're depending on five hundredths of a gram difference in VTF to combat sibilance, you're clutching to straw. I seriously doubt your digital scale even has this kind of ability and is probably just showing meaningless figures beyond the first decimal point, which I'd take with a grain of salt too.

 

[AnzacSonata]

My scale does measure that closely to the decimal points; the thing is, though, I did think moving from 2.35 to 4 grams WOULD make a noticeable difference in sibilance, considering the AT95E's reputation of...well...sibilant tracking.

You all don't think this is possible?

What worries me more is that I have been adjusting tracking force using this scale WITHOUT touching the AS all this time -- I was never told that AS needed to be reset to zero when making small increases to tracking force...

 

[Rockon1]

Another good point by tnsilver. After my own experiences with TT set up I'd start at the beginning. The wires in my tonearm were affect its movement. Literally acting like extra antiskate. I had to find that out first before I could meaningfully set things up.

I'd align the cart first. Then I would zero my antiskate and get the VTF to zero ( float) Carefully check the movement of the arm slightly floating above the record surface (I put my stylus guard down) If all looked well then Id set the TF to 2.5 (for the moment) Check the VTA and adjust if possible or necessary. Then I would set the antiskate and try it. Oh and ,of course, make sure the stylus is clean.(not sayin its not)

What I learned from the helpful folks on this forum is the whole picture needs to be addressed. Bob