Hi George,
John's explanation above is pretty much right, at least insofar as the number of significant poles. There is the electrical resonance and the cantilever resonance that are dominant in the MM cartridge. For the Shure V15V, the electrical resonance is usually in the vicinity of 19kHz when optimally loaded. Its cantilever resonance is around 28kHz. For an MC cartridge, the electrical resonance is pretty far out, leaving mainly the cantilever resonance, which in many cases is about the same as for a really good MM. Shure M91-class cartridges usually have the electrical resonance and the cantilever resonance at lower frequencies, perhaps on the order of 17kHz and 20kHz, respectively. See my article on the VinylTrak preamp in Linear Audio.
In that article I also show a way to mitigate the effect of the electrical resonance by running the cartridge in to a low-value resistive load to create a single pole against the cartridge inductance, this pole often lying around 8kHz and being absorbed into the RIAA EQ. Obviously, one drawback of this scheme is that the HF EQ needs to be adjusted to match the particular cartidge inductance (a pole-zero pair is substituted for the 75us RIAA time constant and the frequency of the zero must be made to coincide with the pole of the cartridge inductance against the resistive load). There is also a modest S/N penalty (not as big as one might think, however). Finally, this technique leaves you with the cantilever resonance, and that resonance is not worked against an electrical resonance. However, two wrongs (resonances) never make a right anyway, so being left with the cantilever resonance is the lesser evil, especially if it is fairly high up like with the V15.
Cheers,
Bob
Yes. Calculate for a high quality MM with low L, low R, which you've pointedly ignored. Like the Grado. Or the Technics. I gave you the numbers a few posts back.
Then calculate s/n and compare to your favorite MC.
Your Technics, as close as I can find, as I only found the EPC-205CMK3 cartridge: 240milli-Henrys, 200pf load, and 47K+500 ohms You find the solution.
Neglecting a) a few typing mistakes here, b)SY’s MM relevant answers here,
I don’t’s see your post as an answer to my third question (number of LP filters in a cartridge).
As to the severity of this electrical filter you describe (*), it can be altered by less capacitance of the interconnecting cables and/or elimination of loading cap in the pre amplifier. (it is a DIY practice).
There were two more entries in my post.
George
(*) Shure had done (**) –and published- more true engineering studies (cartridge as an isolated system, as well as a component interacting with the record/arm/tt) than any other manufacturer of cartridges (of course, engineering entails concerns over manufacturing costs and subsequent item pricing. Target customers were not the tycoons. There were your father, you, my father, me ect)
(**) Spare Denon for it’s DL103, but this too, is below your MC $500 limit.
You didn't look too hard since I already gave you the numbers. Sorry if they don't support your story. 92k for the EPC, higher for the Grado.
SY, please prove your numbers with a spec sheet or the equivalent. I can only go with what I can 'verify'.
Sorry that Google doesn't work in Berkeley.
Here's data copied right off the spec sheet (I've also measured it myself):
Technics EPC-P 100C Mk4 Reviews | The Vinyl Engine
I have one with a bum stylus that you can measure if you don't believe the rest of the world.
Well, your cartridge looks pretty good, better in resonance than the 205CMK3, and I will look for an independent evaluation to find out more about it. However, YOU have not heard the test record, and at this point, I don't think that you could tell 'live from Memorex', '-) so let us now talk about Grados, and their resolving power.
Mr Cordell
As you know, in the mechanical part of the cartridge, there are many LP attributors and many resonators. They don’t all work at the same frequencies, so it is customary to pick only the one-two with the more pronounced effects.
I find that the rest of your post complies with what I know and have experienced so far (therefore no comments or questions), it is detailed and does not contain any unsupported generalisations.
Thank you for participating
George
These have been posted again in the past
High Fidelity Phonograph Cartridge - Technical Seminar
http://shure.custhelp.com/ci/fattach/get/29245/
http://freudhoefer.de/File_Share/Walton.pdf
The annoying part of MC cartridges.
Back when, I could get a new stylus around the corner, both for the cheapest and the top of the line : http://www.diyaudio.com/forums/anal...d-reproduction-few-questions.html#post2494898 A repair job adress was also easy to find, various choices.
Now, it's pay dearly for a cartridge, watch the clock tick away, then see what the discount is on the even more outrageously priced replacement model. No service, no rebuild, with exception of a few as e.g. vdHul.
With retail levels of cartridges going through another roof every number of years, I can not help but wonder what's wrong with those folks.
I know it isn't in the realm of quality that you all are talking about here but I did have an older model Ortofon cartridge that needed a new stylus and I was amazed how easy it was to find on on the internet. One day I will get something better but for now it will have to do. Now if I just had the correct way to set the angle of the stylus I would actually use it!
Only if you're paying; I've got an ex-wife and two lawyers to support.😀 It's not even clear whether this is OEM... fortunately, my ex-reviewer buddy came through and I got a new one gratis.
Which Grados? You still are hacking at them without even a clue as to which one you're talking about. Or are you claiming that they're all the same?
Never tried Memorex, so I can't comment on the thrown elbow.
Listen ...
But, seriously - I haven't done analogue for 25 years - a friend has a decent, highly tweaked setup and got me to listen as he adjusted using spacers under the vinyl. Fascinating, either side of correct the sound lost resolution, became more mid-fi; when nailed, the soundstage opened up, you could hear deep into the recording acoustic ...
The Grado cartridges all operate on the same principle. It is possible that the most expensive Grados depart significantly from the cheaper models in performance, and even RESOLUTION, but Scott did not buy and expensive Grado, did he? OK, Scott, which one do you use?
Here's a pretty believable take on the high frequency end of phono play, including the issues of stylus effective mass/ vinyl compliance and the electrical network of inductive generators:
Cartridge tests
Pretty much what everybody's been saying.
All good fortune,
Chris
Cartridge tests
Pretty much what everybody's been saying.
All good fortune,
Chris
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