The Finish Line for your Phono Cartridge- Stylus Wear by Mike Bodell

I did not own a decent capture tool when I started this. I have since bought a cheap but effective box to do the capture. I have a new copy of the same record for reference. At 1000 hrs I will likely capture the worn stylus on the new record to compare with the earlier captures I shared.

 

Thats good enough I suppose, although one issue I can think of is if you use a worn stylus it might distort just a little even on a brand new copy, but on the other hand a new stylus might also sound ever so slightly different if its sitting a little different in the groove or something.

But do you really need a capture device? I just plug my amp to my PC and while its not fantastic it works until I get myself a good DAC as well.

 

Well, ultimately what we're trying to determine is when the stylus needs to be replaced, so if the worn stylus causes distortion on the new record, haven't we found the point where it should be replaced? I've posited that there are two points of replacement...first is when distortion becomes noticeable, but presumably the record is not yet being damaged...and second when the stylus first hits the groove bottom radius, causing nasty sounds and possible groove damage. I don't plan to push this study to the groove-bottoming point.

I did try my PC. I have a nice HD Audio capture card, but I've never had acceptable results from any computer-attached capture card. The sonics are always poor, which I generally attribute to ground loops and such. I'm not willing to float my system ground to my PC to try to solve this, so a standalone box is next best thing. I only need to unplug the TT and plug into the box, which has its own ground lug for the TT, and thus floats just the TT to the PC USB ground. This seems to work pretty well, and the captures I made had no objectionable hum or induced noise.

 

I recently emailed audio technica regarding my vm740ML, and asked what their recommended stylus replacement hours was, and they replied 1000 hours. They also offer a free stylus inspection within warranty, which is 1 year from purchase date. I will definitely take them on that offer!

 

Got my Dynavectror DV-XX2MKII back from a factory "rebuild". Just installed it on my VPI Scoutmaster with JMW-9 Signature tone arm. Used a Feickert protractor, digital scale and a Fozgometer and Analogue Production test LP to set it up. Now needs to break it in for 20-40 hrs. First LP played was the new Beatles Abbey Road 50th new mix.

 

1000 hours completed. Contact measurement lengths are:

L: 0.41mils
R: 0.39mils

This is fairly significant flat formation and I expect some sonic impact. I will record the new LP with the 1000hr stylus to compare with new stylus and 480hr stylus. Hopefully folks can do similar analysis as before.

Here are the contact photos. Only a small increase in contact patch, but a visible change in profile showing that the patch is now flatter than even 800hrs.

Left Contact


Right Contact


Profile View

 

I started this experiment July 25, and it took until October 2 to reach 1000 hours. This is ~10 weeks, or 1680 hours, so the experiment was running for ~60% of the time, with ~40% downtime for photos, etc. That's not too bad.

 

How did you manage? Dont you have to restart the lp by hand every 20 minutes?

 

Ray- any way you can juxtapose the profile images so we can see 'fresh', the interval at perhaps 800 hours and again at 1,000 hours, in a way that reveals the changes?

 

I used a Technics SL-10 TT, which has a repeat function.

Yes indeed, and I'm glad you asked because what I thought was flat formation appears to be just an optical illusion due to small pieces of dust. Here is an animation of 1000hrs vs 800hrs. Each image has small dust particles in different places which make it look like the right side contact has flattened. It's best to look mainly at the left side contact, which also has some dust but the tip shape doesn't appear to have changed much. So it looks like even at 1000 hours there is not a lot of flat formation. The contacts are simply well-polished.

 

Thanks for this Ray, it's kind of hard for me to discern. Is there a way you could color tint the image of the tip at 800 hrs so that the (theoretically) smaller tip at 1,000 hrs shows up in contrast? I guess part of it is duplicating camera angle exactly which might throw this off? Appreciated...

 

I think part of the problem is the animated gif doesn't seem to be working properly. It's moving very very slowly for me, and this is throwing off the comparison. Here's a new gif without transitions that may help with the comparison. Note that you are assuming there is some change, but indeed I see virtually no change in the shape from 800-1000hrs. The only apparent change seems to be due to the shadows of dust particles.

 

Are we suspecting the stylus wear slower the more its worn? Makes sense anyway.

 

Onward now to 2000 hours!

 

Interesting, yeah, that's easier to see. And yes, also interesting that you are finding less demonstrable wear. I wonder how much has to do with the light tracking force-- maybe Shure was right! (PS as mentioned, most of the cartridges I use track at just under 2 grams, but still). I also wonder- and I know this is a contentious topic- how much groove deformation from repeated play may affect the stylus wear. I may be speaking out of my 'hat'---

 

All good questions and concerns.

I'm seeing significant flat formation on the minor axis (record play direction) but minimal flats forming along the major axis. I can only attribute this to the shape of the groove wear skewing the experimental result. Indeed if the stylus tip had wear flats on the major axis as expected, the flats would likely have worn a bit deeper into the tip. I am confident that the results so far are reasonably representative of what to expect from a Linear Tracking TT with 1.25g VTF up to 1000 hours, but I am worried that going farther will skew the results unacceptably away from what would happen if multiple records with less groove wear were used.

 

...and playing the same lp over and over again for the test period. I suspect that while the record has worn, it has been nicely polished by the diamond tip. So I agree and well done Ray, I'm blown away by your tenacity and this experiment. I believe you have provided proof positive for why Ortofon states one of their stylus tips will last 2,000 hours with care. It could not surprise me if they conducted just such a test to get that result.

 

Can we get a sample of what the record sounds like now?

 

So try a new record in the experiment. Try a different one every 100 hours from now on maybe. I hate to see your experiment end when we're finally getting somewhere regarding hours of use.

Maybe sometime even try a record with low to moderate noise (clicks, pops, and hash), just enough that it is still somewhat tolerable or acceptable to listen to (I realize this depends on the listener), and play that over and over. That would provide more 'real world' abrasive action on the stylus.

 

I'm still pondering how/if to proceed with this test. It seems I'm the only forum member using low tracking force, and a linear tracker, so I guess I'm really only doing the test for myself and a few other interested folks. The very slow wear I've seen is implying that I won't hit groove bottom radius for perhaps 4-5k hours of play, but the contact width (short radius/play direction) has already moved into the region where distortion and frequency response degradation is starting to be noticeable. The contact flat width of ~0.4mils is also wide enough that it may cause more wear on grooves with higher modulation frequencies, so I think we've reached the point where a critical user would want to replace the stylus.

 

You mean audibly, Ray?
I use a linear tracker, but typically track at higher VTF, as previously mentioned. I think the test is still instructive since if you are noticing audible deterioration even with a light tracking force (and, for the moment, assuming repeated play doesn't challenge the stylus as much as 'fresh' records each time), we can still take this as an illustration that wear does occur sooner than one might think- I guess to get a more complete set of data points, you'd probably have to use a heavier tracking force, switching out records periodically. I couldn't imagine doing the cueing manually each time....
Bill

 

Do you also have a sample of before and after where you now audibly hear the distortion caused by the worn stylus? Oh and did you have a recording of how the record sounds now?

 

I still believe your test has produced significant value to this community. Sincerely, thank you very much for doing it. I don't know of course, but I do believe the long stylus lives stated by some cartridge manufacturers–2,000 hours and longer–stem from a test such as this. I mean it is certainly easier to do this test than what Harold Weiler accomplished with mono cartridges. I cannot image that a cartridge manufacturer now would repeat Weiler's tests across the spectrum of VTFs used today. But in a way, your second comment is spot on, this test with the equipment and tracking force employed is not useful to me per se, except as an academic exercise and to slake my curiosity. Yet I find it interesting that on this test, one side of the stylus has worn, while the other has worn much less. Not to mention not knowing fully the condition of the vinyl grooves on the test lp.

VTF on the cartridges I use (now all three are Ortofon) range from 1.8 to 2.4 grams. We know from the 1970s Shure work that VTF makes a difference in wear hours, even as Shure as seen in FAQ has published over time a range in total wear life hours. My main tonearm is a uni-pivot, so I do set anti-skate. My second turntable, a Rega, is mono only, and gets limited use. While my experience may be viewed as on the near end of the bell curve in stylus tip useful hours life, my stylus was "badly worn" according to an industry expert at 800 hours (at 2.3 gms VTF), and I know another Ortofon cartridge (2M Black) user setting 1.6-1.8 VTF where his stylus was worn out at ~650 hours and needing replacement. The expert who evaluated my Cadenza stylus cautioned me that it was best to replace it 200 to 300 hours earlier than I did. I have no reason to believe the man was lying to me, given that he has been doing this type of work for better than 50 years and actually also manufactures diamond and ruby stylus tips.

A reasonable recommendation coming out of what I learned–if the cost was not so dear–would be to check the stylus at 500± hours of play if one uses a VTF above 2.0 grams on a non-linear tracking TT. The cost to do that is not slight, perhaps in the several hundred dollar range if not higher. Unless your cartridge costs more than $1,000 to $1,200, that recommendation is a hard swallow. Even then the recommendation is fighting words for some. To make matter even more complicated, everyone has a different set up, while I do believe in Occam's Razor logic: the problem-solving principle that the simplest solution tends to be the right one. I know what that is for me because I experienced it.

As you know, I've considered getting a microscope set up as you have done, and with your assistance, while to be perfectly frank, I'm not sure what to look for. That point was made precisely by James Henriot of Whest, the manufacturer of the phono preamp I use. So I'm reluctant to shell out the $800± for an appropriate set up, if I remembered the total equipment cost (less camera).

We have talked about sending you my cartridge every 100 hours for an examination; intellectually I like that idea. But to send it to you six times (pre-use included) and return, insured, is going to cost me about $400, not including the risk of inadvertent damage or loss in shipping. That cost would essentially pay to retip my Cadenza Black. So while I'd love to do it, these factors have slowed me down.

Maybe I need to put together a Go Fund Me site for us to follow through. Better yet, how about getting the cartridge manufacturers to pay for this research. We all want to know.

Keep up the good work, Ray. I appreciate it.

 

Actually the two sides have worn almost identically, with good symmetry in terms of contact length in the minor axis / record play direction, which is ultimately what matters for distortion and frequency response.

 

Thank you for that clarification.