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Straight tonearms without offset angle

In the October issue of Stereiphile, there was an article on a tonearm that had no offset angle and therefore had no skating force. The disadvantage of this is at the beginning and end of the record, the tracking angle error was much greater than what you get with an offset angle. For conventional tonearms that have an offset, and require anti-skating, which can never be perfect, the typical tracking error has a supremum of about 2 degrees, and according to online Lofgren calculators, this imposes a second-order harmonic distortion less than 2%. 

I have a single-ended triode amplifier consisting of vintage globe 45 triodes transformer coupled to 833A SETs which drives Magnepans. Such SETs typically have second-order harmonic distortion as high as 10% which does not hurt the sound. A straight tonearm without an offset would have a maximum, or supremum tracking error of just under 10 degrees. If this causes a second-order harmonic distortion of less than 10%, would not this be irrelevant in a SET system? Is there any way of calculating this, or has this ever been studied? 

128x128drbarney1
lewm
13,414 posts
 

There’s a thread on the Viv Float tonearm. I suggest you review it. You are neglecting to mention that such tonearms are mounted so the stylus underhangs the spindle, as is the case for all of the commercially available tonearms that have zero headshell offset. Finally, such tonearms DO generate a skating force except where the cantilever is tangent to the groove; it’s just much less than for conventional pivoted overhung tonearms. I think it’s specious to analogize the HD of your SET with the tracking angle error of an underhung tonearm in the first place. I own a Viv Float, and I like it very much.

pindac's avatar
pindac
2,864 posts
 

Yamaha also have a Vintage Design, as well as Stax and Micro Seiki also experimented with similar designs, but not zero offset that are now Vintage Models.

Yamaha also have a modern design for the Tonearm used with the GT 5000 Table, this arm is wired with PC Triple C. I am an advocate of this wire type, and also with experiences of having been demo’d a Tonearm with this wire type, used as a continuous wire from Cart’ Pins to Phono’ Input. Using such a Wire, as a Wands Signal Path is a very wise choice.

Truglider is another Brand producing Zero Offset designs.  

lewm
13,414 posts
 

Pindac, are you saying that Stax and Micro Seiki once produced underhung tonearms with zero headshell off set? If so, that’s interesting. 

larryi
4,156 posts
 

Even with a straight arm with no offset angle, the tracking angle error could have been lessened by making the arm longer and not underhung.  The reason for this design is not only to minimize skating force, it is designed to be extremely rigid by being short.

I have to say I was surprised, but it does sound good.

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