General question on Carbon fiber tonearms versus aluminum

Theory before the fact CAN move the ball forward faster, vs. endless random wandering.....but of course, listening is essential 

I believe it would be a massive system engineering error to consider the tone arm in isolation....in a sense like letting the junior engineer paste a CF wing on an aluminum airplane.....

back to the music....

In particular, that has been true of the very few carbon fiber tonearms I have heard. They have tended to produce a sound that seems overdamped, lacking in dynamics.

@lewm I have both and the CF one is way less dynamic, less detailed, slower, and ultimately less musical than the aluminum ones. But it does have a taller and more expansive soundstage. I found the same thing with a Yamamoto CF headshell.

Thanks for mentioning the Yamamoto CF headshell.  I own two of them and also an Oyaide CF headshell, and guess what; I like them all very much.  Go figure.  Very neutral sounding, and they do not color the sound in the way I hear CF tonearms do.  Another listener might hear these things quite differently, and I do not mean to sound dogmatic. I am only answering for myself.  To add to it, one of the Sonus Faber speakers, or maybe more than one model, is/are made of CF.  To me they have the same character as that which is imparted by the CF tonearms that I have heard, "overdamped" is one way to say it.  But that character is to some degree present in other SF speakers I have heard, with wood cabinets.  So hard to tell what is going on.

@lewm I compared the CF headshell with my standard magnesium one and, while bass was better on the CF, it lost absolute detail—diminishing the color of brass, for example—and "dried" out the "air."

1+ @elliottbnewcombjr. Theoretically, a carbon are can be made stiffer, without the need for more damping materials and most importantly lighter.
Lighter, shorter tonearms with more compliant cartridges sound better. They have a much lower polar moment of inertia. This allows the arm to better follow low frequency undulations in the vinyl lowering distortion. My guess is this is why Michael Fremer prefers a shorter arm and why some tonearm manufacturers like Schroder go out of their way to reduce mass while trying to maintain a stiff arm. This is the reason behind his minimalist " head shell" design. As for which one sounds better? I have no idea. I will find out as I have a Schroder CB waiting for a turntable. I suspect they can both sound excellent given proper design.