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Protractor vs overhang

O

onlysleeping

Active Member
I have a Technics 1300 (original, not mk2). I have a Technics headshell. My cart is a Stanton 681EEE.

I printed out the Technics protractor from Vinyl Engine and used it to align my cartridge. I then took out my ruler, and the overhang was more like 56mm, not 52mm as expected. If I scoot the cartridge back in the headshell, I can't get the needle to follow the arc from the protractor. The stylus doesn't line up in the two null points on the protractor.

Which should I use - the overhang length of 52mm or the protractor? Using the overhang length set to 52mm, I used the baerwald protractor to align.

Am I correct that the overhang length is 52mm? Should I use that protractor for the 1300?

Thanks!
 
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I use the same protractor for my Technics tables and haven't bothered checking overhang, you don't need to.


That arc protractor uses 2 null points and that is what you want for optimum alignment and performance.

Your spindle to pivot is 215mm, just what that protractor was made for.
 
The 52mm dimension is for when the cartridge is oriented parallel to the headshell. The protractor instructs the user to align the cartridge with the grid, not the headshell.
 
Bob_in_OKC said:
The 52mm dimension is for when the cartridge is oriented parallel to the headshell. The protractor instructs the user to align the cartridge with the grid, not the headshell.
Click to expand...

Yep, in fact, here is the write up for the Technics protractor from Vinyl Engine, note the last part.

Suitable for those Technics turntables that have an arm mounting distance of exactly 215mm, such as the SL-1200/1210/1300/1400/1500/1600 etc. Please check the tonearm database for the mounting distance of your arm before using this protractor. Also note that Technics arms do not use baerwald alignment as standard, so you may have to offset the cartridge in the headshell in order to align with arc.
Click to expand...
 
onlysleeping said:
Thanks! If I align using the protractor, I seem to get a lot more inner groove distortion then if I just measure 52mm.
Click to expand...

I would think if this is the case something is not right.

The stylus needs to be exactly on the crosshairs at both null points. Your cartridge or better yet your cantalever needs to be aligned with both grids.
 
onlysleeping said:
Thanks! If I align using the protractor, I seem to get a lot more inner groove distortion then if I just measure 52mm.
Click to expand...

I have an SL-1300 as well and found that with my AT440 MLa, the 52mm worked fine. With a Sumiko Blue Point no. 2, the protractor worked best (far less distortion towards the ends of records). I was worried at first that my cart points inward (after using the 52 mm jig), but it lines up to the grid that way. My only issue with the protractor, though, was that I could get the cart to follow the arc and to align to the first (outer) point but there was no way my tonearm would swing in enough to get to the second point.
 
onlysleeping said:
Thanks! If I align using the protractor, I seem to get a lot more inner groove distortion then if I just measure 52mm.
Click to expand...

According to KAB, Technics uses a Stevenson alignment scheme in which the goal is to minimize tracking angle error at the inner groove area ("Technics arms follow the Stevenson alignment, designed to optimize performance at the end of the record."). If that's what's working better for you, stick with it.
 
catman said:
G'day all, reading this thread I'm getting confused! If all else fails get a Baerwald two point protractor and try adjusting your overhang as per this guide. http://www.mds975.co.uk/Content/vinyl07.html Good luck! Regards, Felix aka catman.
Click to expand...

The Technics specific arc protractor that's found on Vinyl Engine is based on the Baerwald two point alignment.

Technics does not use that as standard but it is arguably better than a Stevenson alignment.

This should be required reading regarding protractors:

http://www.vinylengine.com/protractor-user-guide.shtml
 
The Technics uses an overhang of 15mm (230mm-215mm). That is achieved when using the supplied gauge of 52mm.

That will not get an alignment according to Stevenson, but it´s not far from.
It will achieve a nullpoint that is some mm (about 5) closer to the spindle than S. But all these different alignment schemes are in reality very alike, so is the distortion.

If one wants to be very pedandic, one could use 53mm instead of 52mm. Then the nullpoint will be closer to the end of record.
gusten
 
I mounted two Realistic (Shure) R 47EB in two identical Radio Shack headshells.
Each one fitted with brand new LPgear hyper elliptical stylus.
One was measured with Stevenson protractor and the other with 52mm Technics measurement.
Both were installed on to a Technics SL-1700 turntable tone arm and balanced with digital scale.
That is as far as I can go with my amateur testing.
As an entry level listener, I prefer the Technics 52mm overhang measurement method and results.
 
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