why is a 13" tonearm design really superior?

Tbg, I use many 12" arms and I discovered that well built decent arms matched with the right cartridges are delivering a wonderful soundstage, also in the deep frequencies - very dynamical but also precise and detailed but not overanalytical.

When listening to the SAEC 8000 I really started to doubt my ears. Believe me I have some other items to compare with. Nevertheless this design is not only technically surprising but also in the sound quality it transports.
Therefore there must be some reason why there is no any other making a 13" design, or is there any?

when experimenting with so called old scholl arms like the FR-66s

Tracking error is reduced with increasing length, but rigidity is reduced and weight increases. I use a 12" Shindo arm and love it.

Dear Thuchan: I agree with Plato, there are several factors that make the " quality performance " of a tonearm/cartridge combination.

I know very well the 8000 ST tonearm and one of its signature characteristics is that is " alive " against other tonearm designs.
It is a very well made and with a quality control second to none. Something that help to lower distortion is to put some kind of damping material all over the arm lift mechanism, I use sorbothane at both sides on the arm lift base.
I like this tonearm that miss an azymuth mechanism and VT on the fly to be " near perfect " device.

I run it with several different cartrdges and one of them that makes a very good match is the XV-1 by Dyna ( not easy to mount in the SAEC headshell. ).
With which cartridges are you running it?

Regards and enjoy the music,
Raul.

Dear Raul, we all know that there are several factors which make a good arm. this was not my question aiming at. But what you mention below is very interesting and I do agree with you on the missing features. I run it with a Titan i (see pic under my system) and an Eminent Ultra Bc. I am looking for another headshell to mount my XV-1s. Could you send me a pic of your sorbotane installation - thanks

"Why are todays tonearm developers not anymore going for a 13" or 14" design?"

I think this has to with cost, most people cannot afford the big tonearms. The 12" are more often then not well in the 4 figures.