Mono Cartridge Question


You chaps have watched me struggle with the issue of my London Decca Reference being irreplaceable, and then joyfully learning that John Wright has a successor after all. You have seen me buy and test three other MI designs (Nagaoka MP-500, Grado Statement3, Soundsmith Sussurro MkII) along with my older MC cartridges (Ortofon Kontrapunkt C and Benz Micro Ruby 3). Since those struggles have led me to owning two SME turntables and four tonearms, I am now torturing myself with the question of whether one of those four should be home to a dedicated mono cartridge. Remember, I only have one ear and cannot hear stereo at the best of times. A mono cartridge for my few dozen mono recordings would be a matter of reduced surface noise and possibly some improvement in dynamics.

I can get hold of an Ortofon Cadenza Mono (two voice coils so not true mono) for about 1600CDN, and a Miyajima Zero for 3450CDN. So the question is this: am I mad to even think about it? Money is not what it once was before I retired. There is no opportunity to go and hear these before purchase, without spending much more than purchase price on travel.

Shall I "make do" with my rather good stereo carts for my mono LPs or is there something better waiting for me when I get out those Parlophone Beatles LPs?

 

dogberry

@wallytools Yes, I understand the theoretical principles involved. The size of the stylus is a factor here too. A larger stylus being exponentially more detrimental than a smaller stylus. My stylus is a 0.65 conical and my arm is a 9 inch set for  Baerwald. I'm getting more noise with newer records than with my older records. For me, noise would be significant inside one groove and then it clears up for the remaining LP.

Hello @fortheloveof,

You asked, "What do you think then of the DaVa field coil cartridge that features a conical stylus? Many, including the few on this forum who don't trash a cartridge they have never heard, claim that the DaVa is one of the worlds' best. Do you think these claims are simply emanating from a love of colouration and that the DaVa cannot by your definition be anywhere near a great cartridge?"

For the record: I have not heard this cartridge, but would certainly like to. 

NO...I am not saying that people love this cartridge because of any colorations, whether such colorations are real or imagined.

What I am saying is that if ANY cartridge has a conical stylus, it CANNOT possibly extract everything there is to get from the groove. This is a metrological certainty that can be calculated and proven in at least four ways I can imagine (one mathematical, two by software and one by microscopy). 

So, if you think that this cartridge is great now...I can only imagine how great it would sound with a playback stylus that was a facsimile of the cutting stylus that was used to create the very groove is it was meant to transcribe (as long as that stylus has been properly aligned to do so, of course - just because you have a fine-line contact stylus doesn't mean you will realize its benefits without some work!)

Now, if someone - ANYONE - has heard two of the same cartridge design but one with a conical and one with a fine line stylus and claimed it sounds better with a conical than a fine line, I'd respond by saying all the variables in the test between the two iterations of the same cartridge have not been fully controlled for, making the experiment one with a negative value. Either that, OR, the listener values an extra bit of lush warmth (and not much more, at that, as the second/third harmonic content generated by conicals aren't very significant) OVER the improvements in focus, dynamics, high frequency extension, inner detail, imaging and soundstaging that a properly aligned fine line contact stylus offers.

I have no doubt it is a stellar cartridge and I want one, but I'll certainly take mine with a fine line contact edge, please!!! 😁

Hi @goofyfoot 

You said, 'The size of the stylus is a factor here too. A larger stylus being exponentially more detrimental than a smaller stylus"

I don't know why this might be the case, but I am not surprised if there is a good reason for it. We have spend little time studying conical stylus behavior, putting our efforts on fine-line profiles predominantly. The one thing I have found to be certain in the last three years of diving very deep into the relationship between the stylus and the groove is that the more I learn about it, the more I realize how much I don't know!  If you can please explain why this would be so to me, I'd be appreciative of it

To date, the only thing I see out of our research is that a larger conical stylus (vs. a smaller conical stylus) differs on where it will contact the groove wall. Larger conical styli track higher on the wall and smaller down further. This is why when some people change to a different cartridge and note how much quieter or louder the groove noise is, they mistakenly attribute the change to the cartridge being better or worse when it can more often be explained by the change in stylus geometry and the elevation of the contact point in the groove. If you've been causing damage to a groove wall and happened to have been using a large contact radius and then changed to a smaller contact radius you might experience a quieter listening experience. All you've done in such a case is ride below the previously made groove damage, so you're not hearing it any longer. This can happen when you realign a fine line contact stylus as well. When properly aligned, such styli will ride at their maximum elevation in the groove. 

@wallytools From my understanding and maybe I'm wrong but I have read this claim, that a larger stylus will still ride far down into the groove wall and the difference in distance between the larger and smaller conical stylus is very minimal. This is why I believe the larger stylus will create more damage, because it is in contact with a larger portion of the groove than a smaller stylus.

@goofyfoot, it is definitely the opposite from what you were told. A larger object will not fit as far down into a 90 degree groove versus a smaller object of the same basic profile.

The degree to which they differ in their elevation on that groove wall can also be easily calculated. A 1mil (25.4 micron) diameter conical will ride about half way down a nominally cut unmodulated groove (50 micron width). A 0.6 mil (15.2 micron) conical will ride about 20% lower. That isn’t small change.

The contact area of both sizes are VERY similar. Why? Because the point of groove wall contact is on the spherical portion of the stylus. (Technically speaking, points of contact with a sphere are infinitely small but in practice you must consider groove deflection.)

Using a spheroid contact area is VERY important to allow for tolerance errors on the mounting of the stylus to the cantilever on the azimuth axis. This is also why fine line styli have a major radius. This is also why proper azimuth alignment has NOTHING to do with the stylus alignment in the groove regardless of stylus profile (up to a point, any way, but that point is usually past 2.5 degrees level headshell and often more)

Now, I would certainly argue that the smaller contact surface area of the stylus to the groove wall, the greater the chance for groove damage because the force is distributed over a smaller area, causing greater groove deformation. This is another advantage of fine line contact styli over conicals and also why a larger conical probably has a slight edge over smaller conicals in avoiding groove damage which is quite the opposite from what you’ve heard.

However, I AM ALWAYS OPEN TO NEW, YET CONFLICTING, INFORMATION. I invite it as it is the only way I’ve been able to help push this industry forward so far.