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Avid Universal alignment guide, Something is wrong

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Avid Universal alignment guide, Something is wrong

Postby BlueNose » 22 Oct 2010 23:41

I borrowed a Avid universal cartridge alignment guide today just to check set up of a vintage table arm and cartridge.

For anyone unfamiliar with this product from Avid it is a mirrored protractor which fits onto the spindle with printed grids and site lines.
The instructions are straight forward & easy to follow & set up was quick and precise as I could get it.

The cartridge is the wonderful Empire 4000 D3 Gold, after a few hours listening I'd thought to try the cartridge on a Technics SP-10 MKII with Graham Phantom arm.

First step I used the ingenious Graham factory alignment jig ,I quickly found out the Empire was not going to work on the Phantom arm due to the fact the over all length of the cartridge.

With cartridge slid back as far as it will go in the head shell the stylus tip protruded a mm a head of my preferred Baerwald setting.

Before removing the Empire cartridge I placed the Avid alignment guide on the platter out of pure curiosity and found that I was able to hit the
centre of the grids with little effort .

I pulled the Empire off the arm and re-checked the pivot to spindle distance which turned out spot on.

Remounted the Empire & then used a Mint arc protractor specifically made for the SP-10 & Graham arm. With a little work I was able to hit the null points & trace the entire arc without deviation.

The final results setting up the Empire cartridge in the Phantom arm using the Avid including the Mint arc protractor show 100% correct with a cartridge that is too long for the head shell.

The question is, what am I missing here?
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Postby Whitneyville » 23 Oct 2010 06:30

I'd guess the headshell screws might have been just tiny bit too tight to let it slide ALL the way back in the headshell slots. I've had the same thing happen to me. :oops: The lead wires could also have prevented the Empire from sliding all the way back too. I could tell you the story of the custom-made spark-plug wires for my truck being "too short" too (I was trying to put them on the "wrong" sides of a V-8 ). #-o ](*,) "Build a fool-proof system, and no fool will use it."-old NASA "space race" saying
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Re: Avid Universal alignment guide, Something is wrong

Postby JaS » 23 Oct 2010 08:53

BlueNose wrote:The final results setting up the Empire cartridge in the Phantom arm using the Avid including the Mint arc protractor show 100% correct with a cartridge that is too long for the head shell.

The question is, what am I missing here?

Hi,
Do all of the gauges use the same geometry/null points :-k

Regards,
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Postby BlueNose » 23 Oct 2010 13:52

Jas thanks for chiming in. Yes the inner & outer null points on the Avid & the Mint are the correct geometry & are in the same positions, measured from the spindle hole.
However using the Avid or Mint I can get the results needed by adjusting the position of the cartridge body & gentle nudges here & there of the platter or protractor. In other words with a little work I can show on these protractors this particular cartridge mounted in the Graham head shell to be the correct set up & alignment.

Now this is the part that is confusing me & has me wondering what is missing or not understanding.


The Graham cartridge alignment jig locks into the head shell itself with a hinged target plate for fine cantilever/stylus adjustments. Simple but engenius design.

The Graham jig shows the overall length of the Empire cartridge is simply too long for the Graham head shell.

With no more room for adjustments this puts the stylus one mm a head of the Baerwald setting marked on the Graham target plate.
My faith lies with the Graham Engineering jig.

The results of my findings with all three devices is a little baffling.

Anyway so much for trying, the Empire is back on another arm and plays records great!



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Postby nat » 26 Oct 2010 14:34

Not just a matter of different geometries -- Stevenson or Lofgren? I do know that the combination of the Dennessen Soundtractor and Technics tables results in the cartridge being very far forward and cocked. Looks odd, sounds okay, but not better (as far as I have bothered to tell) than when aligned with the Technics alignment jig.
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Postby BlueNose » 26 Oct 2010 22:03

nat wrote:Not just a matter of different geometries -- Stevenson or Lofgren? I do know that the combination of the Dennessen Soundtractor and Technics tables results in the cartridge being very far forward and cocked. Looks odd, sounds okay, but not better (as far as I have bothered to tell) than when aligned with the Technics alignment jig.


Nat
The Graham alignment device offers two alternative null points , Seagrave Baerwald position or the Loefgren overhang.
The Loefgren target position is slightly ahead of the Baerwald null point, 3/4 of a mm, a small incremental distance indeed.

This tiny distance between the two overhang positions can be heard though subtle as they maybe slight distortion can be heard as the stylus traverses through the grooves at the beginning then levels off and then picks up again toward the end of an Lp with the Loefgren overhang. Years ago when anyone talked about huge differences in sound using differant null points I never was over whelmed by any huge differences. There not huge like some make them out to be but never the less they do exist.

With the Empire 4000 installed & fully back in the Phantom head shell, measured distance from my preferred Baerwald null point setting the stylus tip of the Empire is positioned a full one mm a head.

If you are unfamiliar with the Graham Engineering products , Bob Grahams alignment jig is built to the same standard as the Phantom arm which involve ingenious designs.
What the Mint arc protractor offers is precise alignment of the cantilever compared to the Graham device, extreme patience involved here.
In other words the Mint ever so slightly edges out the Graham alignment device only in that department.

Understand my point about the Avid & Mint, set up with these would not of shown the cartridge being too long for the head shell.
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Postby Seb » 26 Oct 2010 22:11

Hi,

Avid is producing various tools
http://www.avidhifi.co.uk/accessories_alignment.htm

what is the tool your using ? the universal on or a specific one?

if you're using a specific one (linn rega or SME), you're using an arc protractor and if your mounting distance is not the one intended by the tool, you'll go nowhere... :
http://www.vinylengine.com/arc-protractors.shtml

best regards

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Postby Whitneyville » 27 Oct 2010 06:36

If you're 3/4 of a mm ahead of your "ideal spec", the AVID would only be 1/4 mm beyond where you are now. My old AT-14Sa is about a mm forward beyond the Heybrook's extreamly wide null points, because it sounds better there. I "customised" the Heybrook protractor from here by telling it my arm was 1mm longer, and it's 1.6 degrees off-set to compensate by the alignment calculator. I chose that to reproduce Quad LP's with more separation front/back, and it's superb on normal stereo LP's. I consider it a "tweek" that worked. No, I can't see 1.6 degrees, but my friend's DeWalt telescopic laser level can with ease, and that's what was used to set things, and a machinist's auto-protractor for VTA, and 2 1/2X Donagan OptiVisors, with a 250 watt halogen lamp to work by... :wink: I consider alignment protractors like a car's front-end alignment spec's. I get the toe-in set out 2 degree's on my truck, because I'm an assertive driver, and it makes the steering more neutral and doesn't "push" on sharp curves, and reduces tire edge wear. If my "tweeks" don't work, the alignment protractor brings me back to a known set of points I can reproduce easily, and start over from.
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Postby BlueNose » 27 Oct 2010 14:25

Whitneyville wrote:If you're 3/4 of a mm ahead of your "ideal spec", the AVID would only be 1/4 mm beyond where you are now. My old AT-14Sa is about a mm forward beyond the Heybrook's extreamly wide null points, because it sounds better there. I "customised" the Heybrook protractor from here by telling it my arm was 1mm longer, and it's 1.6 degrees off-set to compensate by the alignment calculator. I chose that to reproduce Quad LP's with more separation front/back, and it's superb on normal stereo LP's. I consider it a "tweek" that worked. No, I can't see 1.6 degrees, but my friend's DeWalt telescopic laser level can with ease, and that's what was used to set things, and a machinist's auto-protractor for VTA, and 2 1/2X Donagan OptiVisors, with a 250 watt halogen lamp to work by... :wink: I consider alignment protractors like a car's front-end alignment spec's. I get the toe-in set out 2 degree's on my truck, because I'm an assertive driver, and it makes the steering more neutral and doesn't "push" on sharp curves, and reduces tire edge wear. If my "tweeks" don't work, the alignment protractor brings me back to a known set of points I can reproduce easily, and start over from.


Whitneyville I'll have to look into what your saying, however is it not true this geometry info is set in stone?

This Empire cartridge along with two other mm cartridges and head shells came with a vintage table purchase just last week.
The Advid universal set up devise was borrowed just to check set up .Lp after Lp it played very well though it couldn't approach the performance of my other table. I just thought to try the Empire in another one of my tables.
Going by the book in keeping with a specific overhang I simply found out the Empire cartridge should not be played in the Phantom arm do to the fact set up would not comply with any specific null point. Adhering to these set rules I think are for good reason Whitneyville.

Pardon me for repeating myself, even though the cartridge installed in the Phantom arm I had no trouble hitting the null points with the Advid including tracing the arc of the Mint, easily.

Once the Empire was set up using the Graham jig ,all that was needed was a gentle nudge of the protractors to target their first null points.
The Advid requires moving the devise for hitting the second null point.

The Mint no, once you target the first null point some adjustment of the cartridge in the head shell maybe required for targeting the second null point & tracing the arc.
You have no such adjustment with the Graham jig other then moving the cartridge in the head shell for one of two null point settings & aligning the cantilever.

This maybe useless information for most here and could even be totally confusing for others. It could also fall into the category of a rare occurrence only experienced by a few.
I just thought I'd share my experience with anyone wanting to use a vintage cartridge with a modern arm.

Finally, there is absolutely nothing wrong with the Advid Universal set up device, its well made with a low price compared to others on the market and I will find a good arm for this Empire 4000 and mount it on my new up and coming turntable project.
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Postby Whitneyville » 28 Oct 2010 06:15

BlueNose, JaS might correct me, but even with a TT specific protractor and a cartridge specific protractor, I can see where a 1/2mm production tolerance could get into the mix. I had to move the downloaded Heybrook protractor from the inner null point to the outer null point, but it worked fine. The Heybrook stock arm is longer than my Grace 707MkII, and is curved instead of straight. Drilling the arm mount board with a drill press and a Forstner bit is hard to be accurate to 1 mm. Even a vertical milling machine and a fixture at best is +/- .003", and the accuracy of the tool bit is usually +/- .001" and you need at least .003" for clearance to slide X diameter through an X diameter hole. Sadly, tolerances add up. I've learned this from re-building a few car engines and many motorcycle engines, and those are all metal. Today we have engine bore honing machines that with a GOOD operator, can hold a +/- 1 micron concentricity, but at a price...a $200 and up per cylinder price!
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Postby BlueNose » 28 Oct 2010 18:46

Whitneyville wrote:BlueNose, JaS might correct me, but even with a TT specific protractor and a cartridge specific protractor, I can see where a 1/2mm production tolerance could get into the mix. I had to move the downloaded Heybrook protractor from the inner null point to the outer null point, but it worked fine. The Heybrook stock arm is longer than my Grace 707MkII, and is curved instead of straight. Drilling the arm mount board with a drill press and a Forstner bit is hard to be accurate to 1 mm. Even a vertical milling machine and a fixture at best is +/- .003", and the accuracy of the tool bit is usually +/- .001" and you need at least .003" for clearance to slide X diameter through an X diameter hole. Sadly, tolerances add up. I've learned this from re-building a few car engines and many motorcycle engines, and those are all metal. Today we have engine bore honing machines that with a GOOD operator, can hold a +/- 1 micron concentricity, but at a price...a $200 and up per cylinder price!


A 1/2 mm or what ever the tolerance your after can really be an issue for a DIY hobbiest, unless they have access to a machine shop.

I know first hand some of the problems that arrise when trying for exact tolerances ,a good example is a Panzerholz turntable plinth project from a while ago.

To make it brief, the biggest problem was the arm boards and fasening the arm base to the panzerholz .
Ever so slight deveations of any kind would throw off the pivot to spindle distance, even high humity would throw out this measurement.

I realized I had to seal the panzerholz soon after I cut it, however that was only one tiny problem.
Thinking that I had to be absolutely perfect with this setting, a 1/2 mm to 1mm out drove me nuts and lead me to another solution for my turntable project.

A solid bronze swinging arm board milled specifally for a Graham Phantom arm, this solved a lot of grief.

Pivot to spindle setting is achieved with a spindle adapter that slides over top of the spindle, swing the arm over and gently press the head shell into the detent. Leave the arm attached to the spindle and gently tighten the single bolt of the arm board and your done that part of the set up.

I do believe keeping within specs especially dealing with such miniture parts as the stylus traversing the grooves all the way through to effects on the tiny fragile signal itself.
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