Linear tracking vs. Pivoted tracking tone arms.

I just found this quote in the DV507 MkII brochure:
"The DV507 bi-axis tone arm has a large inertia for horizontal movement and a very small inertia for vertical movement. We shall now explain the reasons why this is advantageous.

It is well known that a cartridge generates an audio signal by the differential motion between the cantilever and the cartridge body. Consequently, if the supporting point of the cartridge (the tonearm) vibrates, the tonearm motion affects the audio signal.

In these conditions, the signal, which causes the tonearm to vibrate is of low frequency and large amplitude.

In the currently used 45-45 stereo record cutting procedure, low frequency signals are almost entirely recorded in a horizontal direction. This means that the low frequency signal, which can cause vibration in the tone arm, exists only as a horizontal force.

The tonearm therefore must have sufficient effective mass and rigidity in the horizontal plane in order to provide a stable platform for the cartridge.

On the other hand, for the mid to high frequencies, the effective mass of the tonearm should not be too large since the combined mass of the cartridge and the head shell need to be taken into account as well. In particular, where records have a warped surface, the vertical effective mass needs to be small enough to ensure a good tracking ability on such surfaces.

To summarise, the tone arm should have a large effective mass and enough damping in the horizontal plane and at the same time a small effective mass in the vertical plane."

I'm just sayin'...

If you look at an LP groove you see that vertical and horizontal motion are both present. Favoring one over the other sounds tricky to me at best. These days most LPs have variable groove spacing so the arm/cartridge combo has to be ready to move without inducing noise.

Atmasphere my friend has a sota table with an ET arm. I think you are right about the excessive horizontal pressure. I have brought my vinyl records to him and when I returned I noticed groove noise. I am using a basis table and basis vector arm. I think he permanently wore the side of the groove. I will not be bringing back any of my records there again.

If the linear tracking arm was to blame, then I guess all of the Walker tables, Rockports, and Kuzma Air Line tonearms are wearing out LPs left and right. Give me a break.

Kinda have to agree with Ketchup. Was going to say the same thing. Check your friend's set-up accuracy and his cartridge, if indeed there is any basis at all for your hypothesis that his playing your LPs on his rig damaged them.