Tonearm alignment question

You might be able to compensate for the spindle to pivot distance by moving the cartridge back within the headshell.

If the spindle to tonearm pivot point distance is off by 2 – 3mm, will this affect the sound quality.

Yes.

And if the tonearm alignment is adjusted with a 2 point alignment tool to fit this distance error, would this alignment be okay?

There's no such thing as a 2-point TONEARM alignment. A tonearm is aligned at one point only, the design distance from the center of platter rotation to the center of tonearm rotation (aka, the spindle-to-pivot distance). I presume you were asking about a 2-point CARTRIDGE alignment. When discussing technical tools and measures please try to be precise in the use of terms, as to do otherwise causes confusion.

Some (not all) 2-point protractors might allow an accurate cartridge alignment to the chosen geometry (e. g., Baerwald, Loefgren, etc.) despite an inaccurate tonearm mounting distance. This would, however, result in a cartridge mounted non-square to the headshell. The resulting vectors would alter the amount of skating force from the tonearm's design and might alter energy transmissions between cartridge and headshell. This will result in changed sound, though in non-predictable ways.

IME, better sound results when the tonearm is mounted at the proper design distance and the cartridge is aligned using the alignment scheme envisioned by the tonearm designer. Can it be done otherwise? Of course.

2-point CARTRIDGE alignment ... of course, I was certainly referring to cartridge alignment (not tonearm).

That said, I appreciate your comments Dougdeacon ... just what I was looking for. This might be the resultant in the possible mistracking that I'm experiencing and the poor sound on certain recordings, more noticeable on my 45rpm pressings.

It may be, though there are many other possible causes.

With regard to S2P and cartridge alignment, my broadest experience is with a TriPlanar VII tonearm using:

1. a universal protractor that allows tolerably accurate Baerwald cartridge alignment even if S2P is off; and

2. a "Mint" arc protractor custom made for the tonearm; it only works if S2P is accurate and it allows extremely precise Baerwald alignment (orders of magnitude finer than the TTB).

The sound when aligned with the Mint is much less distorted and the vast majority of Mint owners report the same thing, with any tonearm, so there is something to it.

I gather there's some reason your tonearm isn't/can't be mounted at the design distance?

This distance tonearm mounting error can and will be corrected when time permits. For the interim, I have adjusted the cartridge in the headshell to compensate for the error as Brf suggested. Unfortunately, I'm still experiencing mistracking with this adjustment. I guess I will not really know the answer until the tonearm is back at it's proper mounting distance.

Thanks for the useful info Dougdeacon. Sounds like the Mint Arc Protractor is a worthy investment, and one that I will consider. I'm currently using the Graham Phantom custom alignment tool provided with the tonearm and a Turntable Basics alignment tool as a check.

I would recommend correcting the tonearm S2P distance sooner rather than later. You may be causing groove damage with an improperly aligned cartridge.

I have a MINT protractor. HIghly recommended. Definitely the best $100 I've spent on my analog chain. Doug's ME stylus cleaner is right up there too as far as value and effectiveness go.

Taylor,

Nice tonearm! The Phantom is at least the equal of my TriPlanar (arguably better). It will reward the best setup you can do.

I hope you have the the newly redesigned Graham tool that adjusts for the height of the cartridge. The original tool didn't, which severely impaired its accuracy. The new one's an improvement but it still can't match the results obtainable with a fine arc protractor.

I own two TTB protractors and they don't even match each other. Even if they did, they're blunt instruments vs. the micro-surgical precision of the Mint.

Get the MintLP for your table Graham arm configuration. I can tell you from experience that the Graham jig has some error in it and cannot get anywhere near the alignment accuracy of the Mint LP arc protractor.

Great advice ... a Mint protractor it will be!

I think Peterayer makes a good point and that shifting the cartridge in the headshell to accomodate the S2P distance error will not be a good idea. If it were this simple, there would be no need for a correct S2P distance.

Well, shifting it to get eff. length and overhang right is better than NOT shifting it! ;)

OK, I am trying to undertand this thread. I got the Feickert protracter and measured the S2P distance on my table and the mount is 2mm short. Since the armboard has already been drilled, can't remount the arm. What would be the optimum alignment procedure at this point? Thanks.

Go to the calculator at Vinylengine and recalculate your off-set angle and overhang based on the geometry you want to use and the "new" P2S.
It is really easy to do, fast and a swift instrument which you can use with every tonearm.
A mere 5 minute job.
And it is free ....