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protractor recommendations for s-arm

Ant1-Hero

Ant1-Hero

Prince of Tubes
I'm looking to do all of my own turntable adjustments, I HAVE VTA and AS down. But I'm buying a new head shell, leads and cartridge. I have a 1976 Toshiba SR-a270, I think it's a great TT, MDF body, belt driven, isolated motor, in mint condition. But i don't know what kind of protractor to use, or how much over hang should be there. I have read that S-arms like this should be 49mm with a Stevenson setup.

Could I get some suggestions on a good protractor for the job?

Here is a picture, sorry for the low quality

photo1nh.jpg

By milenko20 at 2010-10-16
 
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Go to Vinyl Engine, they have a number of printable ones. They might have the manual for the table as well.
 
I've been on Vinyl Engine but I can never get them to print to scale, i have tried every setting i know, but its always short
 
i set scaling to 0, I'll give it another go , see if I can get it to work, any suggestions for overhang?
 
Overhang is the distance from the spindle to the stylus, measured in a line from the pivot point of the tonearm through the spindle to the stylus. It is, however, often confused with the length of its overhang gauge, which will be a number somewhere in the range of the 49 mm you may have heard. This usage is so common that I wouldn't have bothered mentioning the technicality if I wasn't going to mention the spec I found. Based on the turntable most similar to yours that I could find at the Vinyl Engine library, that dimension would apparently be 15 mm. If you can get the cartridge aligned to a correctly scale protractor, you won't need this dimension.
 
what is the distance from the centre of the platter spindle to the centre of the tonearm pivot bearings in mm ?:scratch2:
 
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Don't worry about overhang. That is a function of alignment and it will be different depending on the geometry you use. When you align a cartridge, either with a protractor or a shortcut measurement (e.g. 49mm) the overhang is automatically achieved.

There is more than one correct alignment or geometry; each is based on a pair of null points, places on the lp where distortion is zero. There were different opinions on which two points produced the best overall sound. You can use Baerwald, Stevenson, the manufacturer's own, or some others, and all are "correct." But since each positions the cartridge differently, the most practical one to use is the one that works best with your headshell--some headshells are longer and have slots farther forward and vice versa. Yours is a shorter one and would work better with Stevenson, which is close to what most Japanese mfrs used for their own null points.
 
I literally aligned my S-arm with the same headshell you have yesterday. Stevenson 60.325/117.42 for me. Works like a charm.
 
Ant1-Hero said:
Is this one Stevenson? it doesn't say on the picture
Click to expand...
Hi,
The EJTM protractor uses custom null points chosen by ear to suit the designers tonearm/records. It's universal if you use it like any other two-point protractor (ie rotate between null points and ignore the angle between the radii). If you can get the cartridge to align at both points it's probably as good an alignment as any? People seem to like it.

If you're feeling adventurous, Conrad Hoffman's Arc protractor generator is a nice tool - just dial in your mounting distance and the geometry you want to align to and it will print out an easy to use protractor. You can even optimise the alignment to suit the minimum groove radius in your collection - although this is probably best left for a rainy Sunday afternoon :)
 
G'day all, each to their own of course but I prefer Baerwald, having used it on three different S shaped tonearms with complete success. Regards, Felix aka catman.
 
assuming all things are equal, does pressure increase on the cantilever when the cart is moved further out (end) of the headshell?
 
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