Steve, you are correct. For those on the list who have not followed past posts by Steve or myself: The contact area of the 'ball stylus' on the record groove surface is greater than the 'doorknob' shape of the C stylus. The weight spread over a larger area of the wax by the ball is more gentle. The more hard surface of the black wax records allowed for greater pressure on a smaller area. Think of it as a Physics problem. If 1 gram of weight is spread over 1 square meter that is not much pressure over the area. A single square millimeter would have one millionth of a gram per square millimeter. A gram over one square millimeter is still not much but if you put 1 gram per square millimeter over a full square meter then you would have 1 million grams. If the contact surface of the ball is reduced to half on the 'doorknob' the effective pressure is thus doubled on the groove. If the contact area is one forth then the effective pressure is quadrupled. Edison had invented the elliptical stylus as a way of saving steps in forming the jewel. The contact area of the groove from side to side stays the same but the fore and aft contact area is greatly reduced. The diameter of the sapphire rod available from supply houses for watch makers bearings were ground precisely so all that needed to be done was to create a clearance bevel and polish the end. The ball and hemispherical stylus were actually more work intensive in order to be accurate which is counterintuitive. Strangely the 4 minute stylus of the H has greater contact area than the diamond reproducers since the elliptical long direction of the H sapphire is in line with the groove direction while the diamond stylus is a point of lesser radius. For those reasons a brown wax is not to be played by a C reproducer stylus and a 4 minute Amberol wax is not to be played by a diamond (heavier weight too) reproducer. I hope this makes sense and this has not been my usual 'clear as mud' explaination. Regards to all, Al PS: Apologies in advance if this missive comes in a odd format, I am on a strange computer which is giving me weird results. _______________________________________________ Phono-L mailing list http://phono-l.oldcrank.org
