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mirror protractor

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mirror protractor

Postby jazzbeq » 27 Nov 2008 01:10

http://www.mintlp.com/best.htm

anyone use on of these? are they good?

Thanks for your help!
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Postby XTRProf » 27 Nov 2008 10:05

Any alignment protractor that takes into account of your tonearm length and that follows the 2 preferred alignments will do. Don't need to be the most expensive. All these others are just slightly better variations of the basic protractors.
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Postby JaS » 27 Nov 2008 11:10

Hi,
Arc protractors are quick and easy to use, but you have to get the mounting distance spot when you mount the arm or alignment accuracy will suffer. A two point protractor designed for the same null points is more forgiving because mounting distance is less important; as long as there is room in the headshell to align to both points you have the correct alignment.

It's an interesting product but It would be nice to know what null points they are using, manufacturers, Baerwald, Loefgren or Stevenson? It's a pretty crucial piece of information to leave out.

FWIW The comment about 'no more inner-groove distortion' should be taken with a pinch of salt - a pivoted arm will always have tracking error and distortion - the only place you get zero tracking error is at the null points :wink:

Regards,
JaS
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Postby Brian C. » 27 Nov 2008 12:09

I use this from Turntable Basics...

Image

20 bucks.


Brian.
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Postby davidsss » 27 Nov 2008 12:21

I have the same one and having the mirror is useful. Mind you my current arm, a Stax UA7, has a little dot on the headshell which you line up the diamond to, this is supposed to align the cart. I tried this, checked it with the plastic Ortofon protractor I have and it was spot on so it seems to work. The mirror protractor seems to have the same alignment as the Ortofon which I think is Baerwald. One of the more useful uses for the mirror protractor I have found is for azimuth. With a mirror you can really see if the cart is level, it does make this more obvious.

DS
Micro Seiki BL51 TT, Stax UA7 Tonearm, RCM Sensor Prelude Phono Stage, Dynavector XX-2 MkII Cart, Rotel RCD865BX Cd Player, Melody I34R amp and Osborn Epitome Speakers.
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Postby andyr » 27 Nov 2008 12:49

davidsss wrote:
One of the more useful uses for the mirror protractor I have found is for azimuth. With a mirror you can really see if the cart is level, it does make this more obvious.



Yes, you can see if the reflection of the cantilever is in the same vertical line as the cantilever ... but that only gives you an approximation that the stylus is riding level in the groove (as it presumes the manufacturing process of glueing the stylus to the cantilever is 100% true).

From that foundation, you then need to:

* adjust by ear, so that the height of the sound stage of a symphonic recording is the same in both speakers
OR
* you use a test LP, a narrow band-pass filter centred around the 1Khz tone which the test LPs use, and look at the crosstalk reading on a 'scope. There is some complex ratio which takes into account possible differences in output in each channel of the cartridge, which enables you to optimise the azimuth.

Regards,

Andy

PS: I just use the mirror and then adjust by ear! :D
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Mirror Protractor

Postby gold928 » 27 Nov 2008 16:18

I've used a protractor called Cart-a-Lign for years. It looks like a boomrang and uses a mirror. I've tried most available protractors(including a Dennesen) and this is by far the most effective. One can be as precise as one wants, but also can be relatively quick. What I REALLY like about this protractor is that it aligns the needle, NOT the cartridge body. This protractor was made in the 80's, but I recently seen one on eBay. After contacting the individual, the seller was the man's daughter. Her father is an engineer and stopped making the protractor, but the daughter stated that they were testing the demand, and planned to make the protractor again. Those of you who have this device, I have the original instructions.
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Postby Seb » 28 Nov 2008 18:54

could you post pictures ?
and the instructions ?

protractor is my passion ;-)

best regards

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Mirror Protractor

Postby gold928 » 29 Nov 2008 03:11

Rats! Seb you got me. I'm shy about posting, I like to read better than I like to post. Two posts is my norm for two to three months. I've never had any luck posting pictures. I have made a picture. If you send me your email address, I'll send the picture and the instructions. By the way, I still have the address of the Protractor's designer. He might make so more!!!
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Postby jazzbeq » 29 Nov 2008 03:22

http://www.enjoythemusic.com/freestuff.htm

there is a protractor from enjoythe music, is it good, will try it this week!

bye
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Postby Seb » 29 Nov 2008 08:43

jazzbeq wrote:http://www.enjoythemusic.com/freestuff.htm

there is a protractor from enjoythe music, is it good, will try it this week!

bye


it's free like all the protractors you can download here :
https://www.vinylengine.com/cartridge-al ... tors.shtml

but if you're using badly the enjoythemusic protractor
(if you use it as an arc protractor, you'll go nowhere)

is there a problem with the protractors we're proposing ?

best regards

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Re: Mirror Protractor

Postby Seb » 29 Nov 2008 08:47

gold928 wrote:Rats! Seb you got me. I'm shy about posting, I like to read better than I like to post. Two posts is my norm for two to three months. I've never had any luck posting pictures. I have made a picture. If you send me your email address, I'll send the picture and the instructions. By the way, I still have the address of the Protractor's designer. He might make so more!!!


you've received am email ;-)

best regards

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Re: mirror protractor

Postby ProfTournesol » 29 Nov 2008 08:56

jazzbeq wrote:http://www.mintlp.com/best.htm

anyone use on of these? are they good?

Thanks for your help!


yes, I've got one for my Funked PT/Kuzma/ZYX. You need to use it in good light and have good eyes (same as any other method). It's alignment coincides exactly with my Feickert alignment tool setup, but is considerably cheaper to buy, however it's specific only for this exact combination of equipment.
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Postby kelso » 30 Nov 2008 19:29

Thought I should weigh in with my 2 cents on the mint tractor.
I've used it recently and found my previous setting to be about 1-1.5mm out which was with the Feickert protractor. This I feel could be due to a few factors:
- firstly, the mint is table specific and fitted so well around the spindle that I had a problem removing it (I was sweating it because it was made of glass and was afraid that it might drop and crack itself on the mat). A protractor that has some play around the spindle could definitely put your settings out of alignment (as was the case with the Feickert which was actually quite a good protractor but fitted better with my previous table)
- secondly, the lines are very fine and well drawn (think its laser etched), you'd definitely need to use at least a x10 magnifier. Even under x30 magnification the lines showed no distortion.
- third is its mirror finish and the ability to eliminate parallax error, plus also the fact that its made from glass I felt that it reflected more light and hence provided for a brighter field of view than the plastic one that came with my arm.
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Postby JaS » 01 Dec 2008 11:24

kelso wrote:I've used it recently and found my previous setting to be about 1-1.5mm out which was with the Feickert protractor

Hi,
Just out of interest were you comparing the same alignment points? I gather Feickert's recommended null points are Løfgren B which would leave your cartridge a millimetre or so further forward in the headshell than a Baerwald design.

Regards,
JaS
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