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Moving Magnet Vs Moving Coil

pastorbarrett

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I've read that advances in manufacturing in recent years have narrowed the gap somewhat concerning MC's reputed superiority over MM. For arguments sake, and perhaps putting aside the preamp variable and assuming adequate performance there, is there any reason to plump for, say the very well regarded AT33PTG, versus one of Audio Technica's top MM's? Obviously specs don't lend too much insight, but let's assume similar stylus shape etc

Many thanks in advance
 

Wombat

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Moving coil are technically inferior. Some just prefer them.
 

Wombat

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Poorer signal to noise, drooping HF, finicky load matching. All well established.
 

svart-hvitt

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Poorer signal to noise, drooping HF, finicky load matching. All well established.

Sounds like a Shure bet, then.

I didn’t know this was all established. Do you have examples?
 

sergeauckland

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Moving coil are technically inferior. Some just prefer them.
Poorer signal to noise, drooping HF, finicky load matching. All well established.

I disagree. MCs have generally a flatter frequency response, less of the presence droop than most MMs, are much more load tolerant MMS are very fussy about capacitance loading, and although most MM inputs have been standardised at 47k ohms, trying to get the flattest frequency response from an MM means messing about with capacitance and resistance. With MCs, as long as the input impedance is around 10x the MC's resistance, capacitance is a non issue.

I accept that MC inputs are noisier due to more gain being needed, but I don't know of any MC input stage that is audibly noisy compared with the background noise of even the quietest LP.

Tracking of MCs is probably less than MMs, but as with noise, quite sufficient for pretty much any LP.

S.
 

SIY

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I've read that advances in manufacturing in recent years have narrowed the gap somewhat concerning MC's reputed superiority over MM. For arguments sake, and perhaps putting aside the preamp variable and assuming adequate performance there, is there any reason to plump for, say the very well regarded AT33PTG, versus one of Audio Technica's top MM's? Obviously specs don't lend too much insight, but let's assume similar stylus shape etc

It's not so much recent years. For example, the Technics MMs of the late '70s and early '80s well outperformed MCs with respect to flat frequency response, signal to noise, tracking, effective tip mass, and bandwidth. To this day, the EPC100C mk4 remains arguably the most accurate magnetic cartridge ever made, at least from a measurements POV; whether one desires a neutral and accurate cartridge is a different question. It is unfortunately unobtanium these days, and the few NOS that I've managed to get my hands on (hat tip to JP Jones for finding these!) suffer from rapid cantilever suspension collapse from the aging of the elastomer over the decades.

Life is tougher at the moment for new production since the sources of boron cantilevers are said to have dried up.
 

Wombat

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I have a Shure V15IV MM and a Technics EPS-310MC MC. Both great cartridges. I am happy to listen to either without fussing over trivial differences. The Technics has that unobtainium boron tube cantilever - a BIG minus.

CD is a significant step-up from both.
 

SIY

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Heh, I have a 310 as well, mine being a P-mount version. It's an excellent cartridge, you're lucky to have one.
 

Wombat

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SIY

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Those were great 'tables. The audiophile community mostly ignored the amazing phono gear Technics was making at the time. Gordon Holt was a slight exception.
 

JP

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(hat tip to JP Jones for finding these!)

I'm in recovery; haven't bought a Technics cart or styli for at least two months.

IMG_0837.jpg
 

svart-hvitt

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Hmmm...I reckon the technical «correctness» of MM vs MC isn’t an established issue after all:rolleyes:
 

SIY

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@JPJ I didn't know you got some 205C Mk3s. How are the suspensions on those?

And when are you getting out here to visit? Jan Didden will be here 10/9 to 10/16, just in case you want to make this a party.
 

JP

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Anything TTDD is suspect. I've one 205CMK3 that appears as healthy as it can be, and it's my second favorite.

October looks good, and far enough out I can plan for it. Let me know a few days in that window that are best.
 
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SIY

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Pick 'em. We'll be here. I'm also going to see if I can round up Scott Wurcer, who usually joins us for these get-togethers.
 

Frank Dernie

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I thought I had a little used 205 mk3 around but can't find it. It was on an SL15 that I bought that often just sent the arm back to rest for no apparent reason. I thought I had removed it and was intending to buy an adapter though maybe I put it back in the arm to give it one last try, it still didn't work and I binned it maybe with the cartridge still fitted. I wish I could remember.
 

JP

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Wombat

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I disagree. MCs have generally a flatter frequency response, less of the presence droop than most MMs, are much more load tolerant MMS are very fussy about capacitance loading, and although most MM inputs have been standardised at 47k ohms, trying to get the flattest frequency response from an MM means messing about with capacitance and resistance. With MCs, as long as the input impedance is around 10x the MC's resistance, capacitance is a non issue.

I accept that MC inputs are noisier due to more gain being needed, but I don't know of any MC input stage that is audibly noisy compared with the background noise of even the quietest LP.

Tracking of MCs is probably less than MMs, but as with noise, quite sufficient for pretty much any LP.

S.

I agree. I confused the tendency of some manufacturers of high-end MC cartridges to produce them with premature roll-off("phile preference?). Inherently, the usually lower coil inductance of MC designs means they inherently can have a higher HF break-point. Senior moment there. When queried I did some memory checking.

MM products tend to come with specs. Try generally finding MC cartridge inductance specs.

Matching: A kind friend gave me a pair of Altec(Peerless) 15095 transformers to use for MC step-ups( I notice 4722s are now about half the price of five or so years ago - another passing fad?). I looked into matching issues and came across this article: Step-ups. The last sentence is one that stood out. He is basically saying you need to be a DIY electronics guy rather than a component swapper to match TXs to typical MM inputs.

FWIW:

Cartridge loading
 
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SIY

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A lot of stuff there doesn't make sense. Sad reality is that if you use a step up transformer, you need an RC series network across the secondary for optimum response. And generally you'll have to determine that experimentally with a square wave generator and a scope. Here's an example.
 
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