A question for the group

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G E

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A question for the group
« on: 8 Feb 2014, 08:47 pm »
My golf ball is not centered in the cup.

How critical is this to getting maximum performance?  Seems like this would impact the cartridge angle.

It sounds really fine as it is, is there more to be had?

SteevA

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Re: A question for the group
« Reply #1 on: 9 Feb 2014, 12:27 am »
In theory centering the ball will give you ideal geometry but, since there is a small amount of play around the cartridge screws which allows for a º or two of rotation of the cartridge, in practice centering the ball may not actually give you perfect allignment.

Steve

threadkiller

Re: A question for the group
« Reply #2 on: 10 Feb 2014, 07:38 pm »
That is incorrect. The ball should always be centered. Something is off otherwise.

rollo

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Re: A question for the group
« Reply #3 on: 10 Feb 2014, 07:57 pm »
   Golf ball ??? What ?


charles

rob400

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Re: A question for the group
« Reply #4 on: 10 Feb 2014, 09:12 pm »
+1 in agreement with Charlie (threadkiller) as usual. My Versalex sounds at its best when the ball is centre of the cup and around 1/3rd of the ball covered by silicone. Also wise to set azimuth dead on with cartridge at centre of LP position and don't over tighten the fixings. Nice and snug is perfect.

threadkiller

Re: A question for the group
« Reply #5 on: 11 Feb 2014, 05:44 am »
Ding ding ding!
Someone else got today's answer correct and moves to the next round...
Congrats!

SteevA

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Re: A question for the group
« Reply #6 on: 11 Feb 2014, 10:44 am »
That is incorrect. The ball should always be centered. Something is off otherwise.
Only if you have the cartridge lined up squarely with the mounting plate. If you dont, centering the ball may produce the wrong cartridge allignment.

Mind you, moving the golf ball may not be enough to fix the misalignment.

Steve

watercourse

Re: A question for the group
« Reply #7 on: 11 Feb 2014, 05:04 pm »
My golf ball is not centered in the cup.

How critical is this to getting maximum performance?  Seems like this would impact the cartridge angle.

It sounds really fine as it is, is there more to be had?
GE, your instincts are correct re: centering ball. IME you center it when the arm is over the LP side. You may have to also move the pulley a bit to get the pivot point central to cup, depending. At least I had to with my used Simplex.

Ditto previous posts on alignment and azimuth, except to add that you set azimuth with cantilever, not cart body, and as SteevA suggests, sometimes the play in headshell comes in handy with certain carts that don't like the 19 degree alignment as much.

This, along with getting damping right, are the most important ways to set up the table to sound it's best. Next, I'd say a good isolated platform and an aftermarket mat.

The frustrating part might be the trial and error process that may be short or long, depending on your cart and patience. However, diligence does pay off and the table doesn't go out of whack once set up.


threadkiller

Re: A question for the group
« Reply #8 on: 11 Feb 2014, 05:31 pm »
Watercourse, you are wrong about azimuth.
Cartridge body, not cantilever.

G E

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Re: A question for the group
« Reply #9 on: 11 Feb 2014, 05:36 pm »
GE, your instincts are correct re: centering ball. IME you center it when the arm is over the LP side. You may have to also move the pulley a bit to get the pivot point central to cup, depending. At least I had to with my used Simplex.

Ditto previous posts on alignment and azimuth, except to add that you set azimuth with cantilever, not cart body, and as SteevA suggests, sometimes the play in headshell comes in handy with certain carts that don't like the 19 degree alignment as much.

This, along with getting damping right, are the most important ways to set up the table to sound it's best. Next, I'd say a good isolated platform and an aftermarket mat.

The frustrating part might be the trial and error process that may be short or long, depending on your cart and patience. However, diligence does pay off and the table doesn't go out of whack once set up.

Thanks for all the tips!  Looks like I need to dig out one of the records I keep at the ends of my stacks for the alignment - one that I don't care about

If anyone has a 3D printer it would be nifty to create a jig that fits on top of the cup. A hole would be dead center and a very slightly larger than the diameter of the golf ball. Align the ball to the hole and you are good to go. It probably needs to be hinged to allow its removal. Otherwise one would have to raise the ball to remove it risking rotation of the post.

I already upgraded the mat. The foam mat had sparkle preventer in it so it was replaced with my home brew cork mat. What a difference and no it wasn't due to changed vta.

Will also be getting a linear power supply.

Greg

watercourse

Re: A question for the group
« Reply #10 on: 11 Feb 2014, 05:44 pm »
Ah yes, a 3D printer would be excellent! For this and many other turntable-related uses!

I posted a thought experiment on the other active thread, which conceptually should work. I'm on vacation otherwise would be reducing to practice and reporting back.

G E

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Re: A question for the group
« Reply #11 on: 12 Feb 2014, 02:15 am »
Ah yes, a 3D printer would be excellent! For this and many other turntable-related uses!

I posted a thought experiment on the other active thread, which conceptually should work. I'm on vacation otherwise would be reducing to practice and reporting back.

How about that!  We had similar Tranes of thought.

Still thinking about this alignment jig. 3D printing is a potentially elegant solution, but I have no printer, nor design expressed as an algorithm nor digitized image of a prototype.

I wonder if any plastic juice cans in the frozen foods section of my friendly grocer have an inner diameter equal to the outer diameter of Amadeus' cup?  The. It is simple enough to find the center and use a compass to scribe a circle with a diameter of a hair more than 1.680 inches. ( the diameter of the modern golf ball). Which is carefully cut out with scalpel or something more precise

That would get us in the ball park!

watercourse

Re: A question for the group
« Reply #12 on: 12 Feb 2014, 02:32 am »
Go for it and report back if possible.

I tend to use materials at hand, both because the templates or jigs I've made in the past have required a few design or measurement iterations. Cardboard typically is a good start, and may be all that is needed in the end.

Speaking of iterations, what you might think about is how to accommodate for different depths/circumferences relative to amount of damping and/or fluid used in the cup. Might be useful to have a few versions of the jig with different circumferences in other words.

If successful, scanning and offering the jig as PDF can hopefully assist others on this circle.

PS you must be a jazz fan, you subconsciously mentioned Trane...  :thumb:

SteevA

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Re: A question for the group
« Reply #13 on: 12 Feb 2014, 10:11 pm »
If you use a jig to align the golf ball in the centre of the cup wont that just push the ball to the desired location but ignore whether or not the suspension point above it is also centred.

If that is the case, as soon as you remove the jig the ball will just move back to hanging directly under the suspension point.

I think, if it is to work as desired, when the suspension point is in the correct location the ball should not be actually touching the jig.

Personally, I don’t see it achieving any more than a bit of eye-balling from an elevated position.

Steve

watercourse

Re: A question for the group
« Reply #14 on: 12 Feb 2014, 10:34 pm »
No, we are on the same page. What I'm suggesting is to use the jig to assist in

1. Rotating the arm pillar to the correct location
2. Ensuring the pulley is in the correct location

While the ball sits in the fluid. You don't use the jig to "push" the ball into place. There is some space between the jig and golf ball, which you will use to help center the ball.

I would say the jig only needs to be close enough to the ball, and uniform enough to be able to either "eye it" better, or so that you can use a ruler or other measuring device to fine tune (if you want/need more precision).

What I'm imagining is that the jig can be a single arc, or two complementary half-arcs - which would approximate what GE's design is getting at. They would "close-in" on the golf ball, and sit on top, just less permanent as the materials are less durable.

watercourse

Re: A question for the group
« Reply #15 on: 12 Feb 2014, 10:55 pm »
One thought for the future: I would be interested to find out for myself whether there is a single point where the ball is centered in the cup both when the arm is in the middle of the LP, and when the arm is in the rest. IME experience so far, there isn't.

The Simplex manual unfortunately does not make this clear, although all drawings show the arm in the rest when centering. I have found that this places the ball far from center when playing a record.

This is relevant because IME distortion characteristics, tracking ability, and azimuth drift changes depending on where you decide center will be. The first two parameters audibly different.

G E

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Re: A question for the group
« Reply #16 on: 13 Feb 2014, 12:55 am »
Good questions.

My vision of the jig is to use it to set the alignment of the golf ball to be as close to the center of the cup as possible. Once the alignment is complete, the jig is removed: it's job is complete until the next time one wants to tinker with alignment. That is why I think it needs to be hinged halves to make it easy to remove.

I would hope the ball is centered regardless of where the headshell is in its arc arcross the record.

I wonder if one of the building supply centers have some plastic/PVC plumbing parts that would suit our purpose?  I think I'll check it out this weekend!

scaleautoart

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Re: A question for the group
« Reply #17 on: 13 Feb 2014, 05:46 am »
GE, your instincts are correct re: centering ball. IME you center it when the arm is over the LP side. You may have to also move the pulley a bit to get the pivot point central to cup, depending. At least I had to with my used Simplex.


New Simplex owner here...I don't have this issue. It stays centered across the whole record. You may want to re-hang the ball and make sure the line is not crossed, etc.

watercourse

Re: A question for the group
« Reply #18 on: 13 Feb 2014, 05:50 am »
Half twist, yes.

Centering issue - not that simple, got it used. Have gotten to a point where azimuth stays put, but not always centered. Did you get yours new?

scaleautoart

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Re: A question for the group
« Reply #19 on: 13 Feb 2014, 05:58 am »
Yes...new...but had to re hang the ball :duh: All is good.  Do you see lots of movement?