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

Yes it seems the real difference up till now is the record. This is in the same line as I have seen between new versus a lot of plays record. I then used two Paul Simon records: 'Graceland' for the test.

 

Thanks for doing all this, Ray.

I compared the 480-480 to new-new with headphones, and I thought I could hear slightly more distortion on he 480-480. But I'm not sure. There also seemed to be more surface noise on the new-new.

In any case, I'm wondering about what the practical consequences of these findings are. I had my old Audio Note Japan IO cartridge for more than 20 years and used it heavily for the better part of probably at least 5 of those years. So my guess is that it has quite a bit more than 3000 hours on it. But the records I have spun many times over those years still sound great.

So I guess at least my takeaway is that if you want the absolute best performance and have highly resolving gear, then you should change your cartridge a lot sooner than previously assumed. It you don't want to obsess too much about it, you will still get good vinyl sound for decades if you do what most vinyl-lovers probably do, i.e. run your cartridge until it starts to sound bad. But of course, act on it when that happens.

And that's a good thing IMO. If we insist that everybody with a record player have to replace or retip their cartridge every 500 hours, then we would soon see the end of the vinyl resurgence, I'm afraid.

 

Nice work Bill Hart (over the decades your diligence as a vinylphile seems to have no end) and thank you Ray Parkhurst for all the great images.

 

Thanks Rob but I didn't really do much of anything other than play host to Mike Bodell; Ray really took the initiative here-
no false modesty on my part--

 

I combined the left channels in MASVIS to compare the tracks. The first one down is with a new record and left channel with new cartridge, right channel with 480 h cartridge. There is virtually no difference between the new and old cartridge, frequency response remains very similar, dynamic range (crest) very similar as well.



Looking at the comparison with new and old record, there is a difference. The old record (blue trace) seems to have lost 1-2 dB above 10 kHz. Dynamic range is surprisingly similar though.

 

I can't imagine this visual analysis would be of much use - the grid is at 10dB increments, but we can hear differences of 1dB or less in volume or frequency response.

It is also in the transients and hard-to-track sibilant areas that we expect more record wear, so even though I can do a FFT averaging analysis of an entire near-sample-accurate-matched recording segment and compute the difference, I still wouldn't expect to find what the ear can in trouble spots.

If not examining the same record captured as-new and after the torture test, we also might be discovering the effects of stamper wear or different stampers used in manufacture, or inconsistencies in vinyl material and fill.

 

Nice analysis, thanks! I was hoping someone would do such an analysis. I don't have the software to do it. It's of course impossible to do distortion analysis on program material, so perhaps I'll use a test record next time. The visual amount of wear on the cartridge would not make me expect to hear much difference between 480hr and new, but later in the wear cycle (1000hr? 2000hr?) I do expect some distortion so a better technique to measure it would be good.

The 1-2dB drop above 10kHz seems correlated with folks' expectations, ie that the high frequency modulations would wear the fastest. 2dB corresponds to significant wear and would certainly show up on a harmonic distortion measurement if the record were test tones and if sampling rate were high enough. Not many of us could discern 2nd harmonic at 10kHz, though I'm sure some folks would claim they can. Actually I am not even sure what harmonic distortion of these levels would sound like at 10kHz. The amplitude drop would certainly be noticeable, but would it sound distorted? Never had the opportunity to experiment with a known level of distortion at high frequency but perhaps others can comment on their experiences.

@Encore commented that the New-New seemed to have more surface noise. I did notice at the 12hr and 24hr (IIRC) checkpoints that the record was getting quieter. Was it removal of embedded debris, or "smoothing" of the groove walls due to wear, or ?? I don't make a final decision on record quality based on a first listen as my experience is that playing a record 2-3 or even more times (with cleaning before each play) can result in a significant reduction in surface noise. But with 1400 plays I think we're in uncharted territory here.

 

Thanks for this, one question though. How many plays is 480 h with this record? Is it one side only?

 

Yes, it is one side only, on "repeat". The actual timing of the side is 0:22:02 so 480 hours is ~1307 plays.

 

Actually, that’s really impressive!! It didn’t dawn on me until now that it is 1300 plays. I never knew that a record would be even close to playable after more than a couple of hundred plays. That makes me even less concerned about record wear

 

Wow. Unless you are really fanatic listening one record, it will last a long time.

 

Thanks, Ray. I continue to watch your experiment with interest and fascination. Vinyl is tougher than most of us think. Makes me wonder what my old deep groove mono Blue Note records must have gone through to sound so rough.

 

Probably 10g of force on a busted diamond from the ole vitriola

 

Yeah, after playing it 1300 times, all it has is 1-2dB drop above 10kHz. Maybe there's something to be said for 1.25g VTF / T4P / Linear Trackers.

 

I loaded Ray's files of the new C-R and 480C-R into my Izotope RX2 spectrum analyzer, took screen dumps and overlaid them in Paint to form a composite image that shows the response deviation perhaps a little more clearly.

If you select the spectra of the silent portion only, you'll find essentially the same response change as what is shown for the entire file in Thomas_A's post. This means to me that something other than record wear is responsible for the HF droop; perhaps a change in SRA from suspension break-in might account for it, or the polishing of the diamond...or smoothing of the vinyl aggregate surface. Whatever is causing it, it's there even in the silent portion between tracks, and so cannot, in my opinion, be related to HF loss of music dynamics.

I'd upload them here and now if I could figure out how. 3rd party linking will have to wait till Sunday as I'm out of time now and I'll be away from the computer tomorrow.

 

The "silent" portion isn't really silent, but is a record of groove noise and tape hiss. If there is sufficient dynamic range to make an accurate comparison, then I wouldn't expect there to be a difference in frequency response between those grooves and ones with higher modulation.

 

If you have 500 records you like and play one of the them on average 1 hour per day, you can listen to these records for 1780 years before the drop of 1-2 dB. I guess your hearing will be long gone by then.

Also you could always change the load a bit to increase the output 1-2 dB 10-20 kHz to compensate for future drops. You would probably have hard time to hear differences up there since the JNDs are quite large. With that in mind, the records would last "forever".

 

I don't expect that the 1-2dB drop can be compensated so easily. The grooves likely did not wear evenly, ie the peaks of the modulation are likely more worn than centers, which are more worn than the troughs. Of course the peaks of the modulation don't correspond to the peaks of the signal, but indeed the change of shape of the groove does cause distortion, not just a change in level. Now, a more sophisticated DSP may be able to compensate such wear to an acceptable degree, but I personally don't want my grooves messed with digitally if I can avoid it. As you say though the JND is large, so perhaps just a levels shift, or maybe do nothing at all. I'm not personally so worried about 1-2dB at 10-20kHz.

 

No it will not be perfect, but it is at least something. I have already a bit higher output 10-20 kHz and it is a compromise in loading.

(I saw that you linked from VE to the analysis, good! I am unable to post at VE since I messed up when I tried to update my e-mail adress in my user info, and got banned for multiple accounts).

 

Yes, so in a real-world situation (for most) where you have run your cartridge for more than we now know is recommended a record may not last that many plays, so maybe the couple of hundred times is not so far off ...

 

I let this checkpoint go an extra 24 hours, so instead of 576, I pulled it at 600 hours. Rounds things off nicely.

Left contact grew from 0.32mil to 0.35mil
Right contact grew from 0.31mil to 0.34mil

I still don't see noticeable flats forming in the profile view.

Here are animations of 600 vs zero hours:

Left


Right


Profile

 

Ray-- I'm wondering if the relatively low tracking force---1.25 grams-- is a factor here. I don't know what the average is for most people; the cartridges I use tend to track just below (and in one case, just slightly above) 2 grams. Maybe Shure's quest for lower tracking forces back in the day was very sensible - I don't know if you remember the ADC XLM and the Black Widow arm--the era of really low mass, low tracking force. That approach seemed to lose favor when MC came into vogue.

 

The low tracking force is due to the use of a linear tracking / T4P turntable for the tests.

Note that there are MC P-mount cartridges as well, but indeed many more in standard mount. I expect it was hard for mfrs to get MC's to track well at 1.25g. My MCs don't seem to wear very quickly either.

 

Beautyful pictures. Have You seen any difference in 'vinyldust'?

 

I saw a bit less dust this time, even though the play time without cleaning was longer (120 hours).