The guru on fuses:

It was a fine but failed attempt to appear superior theaudiotweak, but digitally, if someone cared, you can actually differentiate from the initial signal and reflections quite effectively in the digital domain similar to how Kippel can achieve anechoic like testing at bass frequencies, even in a room with reflections at wavelengths < bass frequency measured.

The question would be why would anyone bother, when they could just start with digital except to attempt to recover information (once and only once) from old records. Of course that has already been done with a multitude of digital techniques. Keep swinging that hammer.

So what is the input signal when it has been corrupted by the same mechanical reading of the shear wave which is much of the wave type pressed into the vinyl. Those wave motions are the shear and also mixed in are the polarities of shear that travel the material. Like to see the removal of the interference in the digital domain without corruption of the original signal.  Like to know and like to hear the results. Tom

Shear wave elastography or something equivalent if offered by
Kippel would be a novel and useful tool to measure surface vibration and deformity of a speaker and any material or device even a fuse element. In a short search there is no mention of wave types on their site that I can locate.  I guess I will write them. Tom

OMG ... do you even know how "sound" travels in a material. Transverse waves are not the only method. Even solids have longitudinal waves.  When vinyl is cut, it is intentionally cut at reduced speeds to reduce impacts of vibration ... you know the non-fancy name for what you mainly call shear. But really, who cares. The vinyl is already pressed and if it is new vinyl, it is pointless you should have just stayed digital.

I know how sound travels in materials..

After seeing this video and recognizing the motions we at Star Sound developed the Platter Ground this video https://youtu.be/GuCdsyCWmt8 puts a scope on the implications of shear wave generation.
I met with a fellow company member who is a geophysicist and we wrote the following in September of 2016.

The stylus makes shear because it is physically bumped as it travels in the groove in the groove. This is a purely mechanical process. Part of the shear energy mechanically excited by the stylus travels through the record to the center or the outside of the record depending on the movement of the stylus. The energy in the vinyl interferes with the sound when it bounces off the edge or center of the record, and travels back to groove creating an additional vibration on the stylus. The stylus has such a fast shear velocity that the energy - both the music and the interference - that it then can be translated very quickly and cleanly into electrical pulses.

The shear going to the outside of the record will always be behind the stylus because it is having to travel the distance to the outside edge and back plus the distance the stylus has moved since the shear wave was created. The distance the stylus moves is increased to the shear traveling to the outside because the outside edge is physically moving faster than where the stylus is. This is a velocity that has an acceleration component due to the angular momentum of the record - ie we are now into an equation with a first and second derivative. The vinyl has a slow enough shear velocity that the shear going toward the outside edge will miss the stylus on its return from the edge and go to the center of the record. The shear energy going to the center of the LP will move through vinyl that is traveling slower and slower, so when it bounces off the center label it will could be in front of the stylus. This is the energy that the Platter Ground removes. Also since the stuff bouncing off the outside edge of the record is behind the stylus, the only shear that can interfere is the shear coming from the center of the record, not the outside edge.
The mechanical world has many aspects that create complexities. The rotation of the record only affects the energy traveling in it, not the energy going from the stylus to the magnets in the tone arm (the arm is not moving much).
I suspect that the platter ground creates the greatest effect when the stylist is on the outside 1/2 or so of the record.

More discussion.

We see that the needle is creating a diagonal side to side motion creating the information of stereo. That diagonal has a shear component and a compressive wave component moving through the record. The weight on the center removes both. The slit in the Platter Ground allows the compressive waves to go into the air (not big enough to hear)
The shape of the inverted cone with the slit. It fans out the waves that then interfere with themselves which can’t go around the cone because the slit breaks up their travel. Those that may escape will travel the height of the cone. The energy is dissipated as a very small amount of heat.

Mechanical grounding of the speaker is real because the movement (vibration) of the center of the speaker sets shear waves moving through the speaker membrane as well as the speaker cabinet. Only one of the polarities of shear makes music the other interferes.


I have no direct experience but some of what I see with the hex mat will reduce shear wave interference on a record similar but different to our Star Sound Technologies Platter Ground. http://v2.stereotimes.com/post/star-sound-technologies-platter-ground https://www.hexmat.net/

That’s all for now.

Tom