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How critical is alignment error??

I would appreciate advice regarding the following issue.

A tech recently installed a new tone arm on my old turntable base. The new arm has a spindle to pivot (S-P) distance of 222 MM. Upon return of the TT with the new arm, I noticed that the S-P distance was about 5 MM short, say 217 MM. I own a protractor and checked alignment. As I suspected, the cartridge overhang was about 3-4 MM over the sweet spot indicated on the protractor. BTW, I was able to move the cartridge back in the arm shell towards the pivot point, but even with the maximum adjustment, as stated, I was still off 3-4 MM.

My question is how much distortion will this error introduce in the playback? Ordinarily, I would ship the TT right back to the tech for adjustment, but I am reluctant to do so because of the possibility of damage from shipment. Further, I suspect that the fix will entail cutting out a part of the undercarriage in order to accomodate the larger arm and I suspect the tech will argue. The old arm had a S-P distance of 215 MM. If the error is signifant, I will have to reconsider what may next steps will be.

Thanks for your advice.
bifwynne
elizabeth
6,726 posts
 
Well, if you and he agreed to stick the new arm in the old hole, then you are in a bad spot. IF he was supposed to drill a new hole, and fix whatever issues doing so would entail, then it is his fault, and he needs to fix it. i would bet, though, that due to a mutual misunderstanding you got what you paid for. An arm put in the old location.
For a tech to seal the old hole properly and drill a new one, would cost more, perhaps much more. If you discussed price, this is one point that should have been brought up.
Sorry your arm is not properly located.
I would discuss it with the tech before jumping to any conclusions.
bifwynne OP
2,069 posts
 
Elizabeth: Any comments about the question raised in my original post, i.e., how much distortion will the overhang error introduce in the playback?

BTW, I did not bargain shop for the work, and yes, it was stipulated that he was to do the work in a "workmanlike" manner, which means, the right way. As far as drilling holes, I found instructions on the web which explained how to install the arm in question on my TT and sent it to him. And yes, the installation instructions contemplated drilling out part of the undercarriage to make room for the larger arm.
rodman99999
3,557 posts
 
How important? In a word, "VERY"! Then again, it all depends on how important it is to you(can you hear the difference, or will you obsess about it regardless?). Personally; It would bother me. This recent article will give you some excellent insights: (http://www.stereophile.com/features/arc_angles_optimizing_tonearm_geometry/)
audiofeil
4,011 posts
 
Send the "tech" pictures with measurements and ask for your money back.

Then find somebody who knows how to do the work properly.
syntax's avatar
syntax
2,033 posts
 
That error is not subtle. It is in analog terms not in the wrong street of town, it is like being on the other side of the world.
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