why is a 13" tonearm design really superior?

Mathematical explanation:

The cartridge traces out an arc as the arm moves from the golder to the center of the record. When the arm is short this arc is very curved on the region between the holder spindle, where as if the arm is longer the arc becomes less curves. Now, when the arc is bigger and relatively less curved, it maintains tangency for a brief period just like the short arm, but the error dur to the curvature is minimzed. I suppose you can call it more tangent if that makes any sense.

I promised to report about the 24" tonearm I have seen on a pic - it is a design of German tonearm designer Fuchs. A friend of mine told me that it sounded very good. 24" inches - not too short...

We next aught to work on a 24'long, what say you?
Like a low resonace pool-cleaner tube?
Will like major minimise the tangent error, no?
Got to have some fantasie else things are not moving foreward here, I say.

at the High-End in Munich the Italian designer Horo presented a turntable in the figure of a long Steinway piano. He mounted a tonearm in the form of a violin bow, properly a 30" design... I never listened to it.

During my e-mail exchanges with Bob Graham when I recently upgraded my 1.5t to a Phantom Mk ii, he indicated that he is not in agreement on "longer tone arm length means superior anything" when viewing the tone arm a comprehensive whole.

He felt his standard Phantom Mk ii (which I believe is 9.5") is a world class tone arm - period. Bob indicated that he did develop the 10" Phantom Mk ii arm wand for the sole purpose of accomodating those TT owners who use a ring clamp of some sort, like the VPI super platter with ring clamp. I have a TNT IV with super platter and ring clamp. Without the 10" Phantom Mk ii, the ring clamp would grind against the Phantom - not good.

I do not understand the science behind these discussions, but I wanted to share the opinion of one of the "masters" in this area.

I like Graham arms, so for me, I will accept Bob's design decisions. For others, maybe not so much. That's the beauty of our hobby.

Brent