Stylus Profile Discussion

mijostyn

Cleeds, yes in many circles you are correct but it does depend on how you look at the angles. At any rate 92 degrees for most profiles is to close to dead vertical 70 to 75 degrees is more like it. Or 15 to 20 degrees if you look at it the way my old brain does, degrees off vertical. I’m not sure where this 92 degree thing came from ... If you put this axis at 92 degrees you’ll almost be dragging the tonearm on the edge of the record. But I will have to review the subject to see what modern convention is.

There are long-standing, widely-recognized definitions for Stylus Rake Angle and Vertical Tracking Angle, and those are the definitions companies such as Shure recognized. There is no "modern convention" that has replaced those clear definitions, and I don’t understand why you seek to reinterpret them. I suggest you read the March, 1981 Audio magazine for the article by Jon Risch that graphically explains these angles and explores why they are critical.

From what I have learned from logic is that ''if the premise are not
true'' the deduced statement can't be true. There are to many
assumptions by your deductions dear chakster. If I am well informed
the records (old and new) are not as ''sensitive'' as you assume.
Even 5 g VTF seems to be no problem. There is also ''elasticity'' of
the vinyl involved. If your ''dramatic'' description is true we who
use ''modern styli shapes'' + tonearms with very good bearings 
would throw away all records made before, say, 70is . BTW
nobody assume, to my knowledge, that records are perfect. 
There are then obviously other reasons why we love them.

The information on the record is on the left and right side of the groove wall, records used for decades with conical stylus degrade in sound, but if you will look under a microscope on conical stylus you will see contact area like a dots. This contact area only wear off a small part of the vinyl groove wall. But the actual groove wall is deeper, and huge part of this groove wall with music on it remains untouched by conical stylus (with very small contact area). Would you argue about it ?

The goal of the MicroRidge, Stereohedron or SAS is wider contact area, it is a line, not a dot/points. This line goes deeper and has much better contact with untouched part of the used old vinyl. The tracking force distributed over the larger contact area and has much less record wear factor.

Playin’ OLD (used) records with LineContact stylus is a clear benefit, because if you’re playing those record with the same conical styli then you exploring the same worn part of the groove wall just like previous owners for decades with their awful cartridges.

I know what i’m talking about, because 90% of my record collection is vintage (used) vinyl from the 50s - 80s.


The owner of modern re-issues are free of this problem, because nobody used their records for 30 years with conical or elliptical tip on cheap turntables. And even if they are buying a user reissues the time of use is very short compared to 40 years old records.

There are many articles about it online if you’re still not aware of it.

The record are very sensitive to wear factor, but diamond is not sensitive because diamond is the hardest material in the world. Vinyl is not. However, the diamond stylus life span in 2000 hrs max, so think about vinyl life span. Vintage records definitely worn, but where exactly on the groove wall they are worn is depends on the stylus profile.

To realize record wear factor quicker you can make a dubplate (accetate) aka lacquer disc at any pressing plant or disc cutting studio. The accetate degrade in sound much quicker than vinyl. Also styrene records degrade in sound very quick compared to vinyl. 

Looks like the second post by Millercarbon nailed it on the head.  You guys go on and on about absolutes which never really pan out in music reproduction.

If your goal is real music reproduction then you are going to have to listen. Or better yet adjust listen and compare.  Because someone plays with a few machines and write in a scientific format, does not constitute a proof in audio reproduction.  

So I guess the moral of the story is if you want read how great your playback system is match your system up with all stuff you can read.  Or maybe you want to listen to it for your subjective enjoyment regardless if the tone deaf, self proclaimed experts, tell you the numbers on the variables they chose are wrong.  How that for a run on sentence??? I really care about Music , grammar not so much!!!

Enjoy the ride
Tom