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View Full Version : Stylus wear - it happens


sgraham
03-08-2003, 09:05 PM
Time was when most record collectors realized that their stylus would eventually wear out, but I have the feeling that nowadays not everyone knows this.

In fact not long ago a magazine published a misguided thought experiment (the editor really should have known better!) to show that diamond styli did not wear out. This is just wrong.

I have seen the evidence with my own eyes.

Back in the days when I worked in the repair dept. of one of the first "high end" shops, I had the opportunity to examine numerous stylus assemblies through a special stereomicroscope made by Shure for the purpose. It takes a little while to figure out what you are looking at, but once you get familiar with it it's easy to see the flat spots on worn diamonds. Typically an eliptical stylus would show significant wear after somewhere between six months and two years of use.

The "micro-ridge" type of stylus had not come out yet, but of the types available at the time, I never encountered a stylus that did not wear out. It's true that all of the "fine-line" stylus shapes (from Shibata on) are likely to wear longer, perhaps dramatically so, but I'd still want to have them checked annually.

The question is raised, how can a hard diamond become worn by playing soft vinyl. I don't think the exact mechanism is known, but here is a theory that has been suggested: The points of contact between the stylus and the record groove are very small, so even with tracking forces of only a gram or so the actual pressure at the point of contact is very high. It is suggested that the heat generated by friction, particularly on highly modulated, wide-band records, with the stylus being thrown around violently at up to 20,000 vibrations per second, or even more, is sufficient to carbonize the stylus at the point of contact. Whether that's true or not, it's indisputable: stylus wear happens.

Often the stylus suspension mechanism will also wear (i.e. dry out), resulting is poorer tracking performance and sometimes higher distortion.

Playing your precious records with a worn stylus is a bad idea. The edges of the flat spots developed on the diamond will act like little chisels, etching distortion into the grooves permanently.

Listening isn't a good way to check to see if the stylus is worn, because, as the old saw goes, by the time you can hear it the damage (to your records) has already been done. So I suggest that those who are still into vinyl find a dealer with a good stereomicroscope and experienced staff and take their stylus in for an annual checkup.

And be careful, if you're thinking about buying a second hand cartridge.

Stax Fan
03-08-2003, 09:32 PM
quote from sgraham
Typically an eliptical stylus would show significant wear after somewhere between six months and two years of use.

This is somewhat misleading. One can't make a blanket statement like that about stylus wear. It's all about how many hours you have on your stylus, and how many hours your particular stylus can endure before succombing to wear. Different folks listen with different frequencies...so it depends. The higher the quality of the diamond from which your stylus came, the longer the life. Of course, the shape comes into play as well.

quote from sgraham
The question is raised, how can a hard diamond become worn by playing soft vinyl. I don't think the exact mechanism is known, but here is a theory that has been suggested: The points of contact between the stylus and the record groove are very small, so even with tracking forces of only a gram or so the actual pressure at the point of contact is very high. It is suggested that the heat generated by friction, particularly on highly modulated, wide-band records, with the stylus being thrown around violently at up to 20,000 vibrations per second, or even more, is sufficient to carbonize the stylus at the point of contact. Whether that's true or not, it's indisputable: stylus wear happens.

True, true, true. I'm not sure about the exact figures, but the heat generated is around 300 degrees F, I believe...and the force is something like a couple of tons. It's crazy, but it's physics. Like he says, it's all due to the high degree of concentration from the extremely small contact area.

quote from sgraham
Often the stylus suspension mechanism will also wear (i.e. dry out), resulting is poorer tracking performance and sometimes higher distortion.

The suspension will dry out faster in more humid environments...like Ohio in the summer. ;) Stylus treatments containing any oils can also dry out the suspension if they come in contact with it. This can happen from sloppy application or by the treatment creeping up the cantilever over time. Oil rots the rubber or elastomers used in most cartridge suspensions.

quote from sgraham
Playing your precious records with a worn stylus is a bad idea. The edges of the flat spots developed on the diamond will act like little chisels, etching distortion into the grooves permanently.

Words of wisdom.

quote from sgraham
Listening isn't a good way to check to see if the stylus is worn, because, as the old saw goes, by the time you can hear it the damage (to your records) has already been done. So I suggest that those who are still into vinyl find a dealer with a good stereomicroscope and experienced staff and take their stylus in for an annual checkup.

Excellent advice. DON'T wait until you hear it. That's like waiting until your teeth fall out to go to the dentist. Too late.

(edited for accuracy in quotes and to whom responses refer)


__________
AC

sgraham
03-08-2003, 09:49 PM
I said:

"Typically an eliptical stylus would show significant wear after somewhere between six months and two years of use."

Arin replied:
"This is somewhat misleading. One can't make a blanket statement like that about stylus wear."

It's true, one can't make a blanket statement about how long a stylus will last. This was typical for the eliptical styli that our customers brought in. I thought it might be a useful point of departure.

Stax Fan
03-08-2003, 09:59 PM
Sincerest apologies, Steve. After a quick run-through of your post, I mistakenly thought it was from the article in the magazine you mentioned. Sorry if any of my wording was in a disrespectful tone. I really oughta read slower.

My point about the blanket statement was just that. Hard to say how quickly or how long it will take stylus wear to set in with so many variables. Under ordinary circumstances, I suppose you're closer, but there's plenty of variables at play. FWIW, I didn't make a generalization...just commented that it depended on several variables.

Full of excellent advice, to be sure.

Again, my apologies.


__________
AC

Metralla
03-09-2003, 12:13 AM
In the early '80s I was living in Brisbane, the capital of Queensland (Australia) and every year they would have a hifi show in one of the major hotels. The Garrott brothers would always attend and they'd bring their microscopes. Audiophiles were encouraged to drop in with their favourite cartridge in hand and have it checked out by the experts. Those were the days.

Regards,
Geoff

michael w
03-09-2003, 03:14 AM
This whole "examine under a microscope" thing is fraught with problems unless the person doing the examining has the experience to know exactly what the stylus profile should look like. What passes for damage on one profile may actuaaly be normal for another.

And as many experts like Jonathan Carr of Scantech have pointed out, under normal use, it is usually the cartridge suspension that gives out before the stylus.


cheerio

sgraham
03-09-2003, 10:05 AM
Originally posted by michael w
This whole "examine under a microscope" thing is fraught with problems unless the person doing the examining has the experience to know exactly what the stylus profile should look like. What passes for damage on one profile may actuaaly be normal for another.

It does take some experience to know what you are looking at. However flat spots caused by wear are almost always asymetrical, that is, there'll be more wear on one side of the stylus than on another. If you see that sort of asymmetry there's almost certainly a problem no matter what the stylus shape is. It does help tremendously if the microscope is stereoscopic and built for the purpose.


And as many experts like Jonathan Carr of Scantech have pointed out, under normal use, it is usually the cartridge suspension that gives out before the stylus.


I can only speak from my own experience, and that is from the days before fine-line stylus shapes were common: when I was looking at styli, it was the wear on the diamonds that was of greatest concern.

Beagle
03-10-2003, 07:54 AM
Boy, I'd hate to invest in a mega-buck cartridge if I had to retip after 6 months! Imagine a $7000 cart that was actually ruining your records within a year. Ouch!

I guess the smart thing to do would be to invest in a Grado Gold or Ortofon OM20 and stock up on replacement styli and enjoy the music with no worries.

Of course, if you are a lawyer, surgeon or talented baseball player, you have no worries period. Throw your Clearaudio Insider away after 6 months and buy a dozen more.

michael w
03-10-2003, 03:15 PM
LOL

Under normal use I'm sure you'll find your $7K cartridge lasting much longer than 6 mths.

Now your second comment has some real merit.

I know quite a few users of exotic cartridges (my self included) who have bought cheaper cartridges to tide then over until they could afford that genuine factory rebuild, only to find that cheapie still in their tonearm 12 mths or more down the track....

:D