MM vs MI vs MC

[watchnerd]

Just for holiday giggles, I swapped out one of the several MCs in my collection (in this case, it was an AT33SA) for the only MM/MI collection, a Nagaoka MP-500.

Granted, this is a fairly top end MM/MI, with a boron cantilever, special line contact stylus, and these days, a very high price for an MM/MI. ($949 from LP Gear!).

Aside from the obvious increase in output (from 0.4 mV to 3 mV), channel separation and channel balance specs are close between the MP-500 and AT33SA.

And, dammit...

The MP-500 sounds pretty darn good.

Better at many things than the previous MC.

So I'm at a loss to explain what I'm hearing without delving into audiophile creative writing porn prose, but the MM sounds more 'blended' and less like 'separate instruments'. The bass is also 'rounder' (more instrument body resonance, less string), although I don't think it's deeper.

Verbal blathering attempts to describe sound aside:

If an MM/MI/MC had the same stylus, same cantilever, and similar channel separation, freq response, and channel balance specs, why should they sound so different from each other?

Can the difference in sound all just be differences in cartridge body resonances and LCR loading parameters?

And thus making the engine type rather overblown in grand scheme of things?

 

[watchnerd]

FWIW, here are the lab test results of the MP-500 just in case it has any bearing on the topic:

http://www.milleraudioresearch.com/download2011/reports/yb11/nagaoka_mp500_mm.html

 

[MakeMineVinyl]

If an MM/MI/MC had the same stylus, same cantilever, and similar channel separation, freq response, and channel balance specs, why should they sound so different from each other?

Can the difference in sound all just be differences in cartridge body resonances and LCR loading parameters?

And thus making the engine type rather overblown in grand scheme of things?

The MM has a greater mass to move than the MC. That's the 'advantage' people who like MC's state.

 

[mhardy6647]

Are you familiar with the Korf Blog, @watchnerd ?
It's pretty good (even though he has an angle, so to speak, as it turns out).

http://korfaudio.com/blog

I think that all (and certainly virtually all) of my favorite "MM" cartridges are, in fact, of the MI kind (and FWIW).

Now, if you want to get out one the really way-out, whacky end of cartridge design, well... there's Dave Slagle. I am a big Dave Slagle fan, but generally cannot quite afford (i.e., justify) his wares.

http://hifiheroin.blogspot.com/

 

[watchnerd]

The MM has a greater mass to move than the MC. That's the 'advantage' people who like MC's state.

Yes, that's commonly said.

But it's also less true of MI's vs MC's.

Also, with sufficient force the higher mass should have equal acceleration, right?

F=ma(2)

 

[watchnerd]

Are you familiar with the Korf Blog, @watchnerd ?
It's pretty good (even though he has an angle, so to speak, as it turns out).

http://korfaudio.com/blog

Nope, never heard of Korf, but I see a lot of cartridge / tonearm articles.

Is there a particular article that ties in to the topic?

 

[mhardy6647]

Nope, never heard of Korf, but I see a lot of cartridge / tonearm articles.

Is there a particular article that ties in to the topic?

No, just general vinylista stuff, but a little more evidence based than some.

 

[watchnerd]

I think that all (and certainly virtually all) of my favorite "MM" cartridges are, in fact, of the MI kind (and FWIW).

Supposedly the Nagaoka "moving permalloy" is a type of MI.

 

[mhardy6647]

Supposedly the Nagaoka "moving permalloy" is a type of MI.

sounds like maybe, since it's not a magnet (I presume) that's moving.

 

[watchnerd]

sounds like maybe, since it's not a magnet (I presume) that's moving.

Here is another weird design note about the MP-500.

I have no idea if this is true:

"Peter Pritchard founded Audio Dynamics Corporation in New Milford, CT in the early 1960s. His original ADC-1 (moving mass: 0.6 mg, needle compliance 20x10-6cm/dyn in all directions, contact pressure : 1 pond or less on top of top tonearms) was a groundbreaking product. In fact, all ADC pickups are characterized by extremely high needle compliance and low contact forces, and he followed this approach in a number of successful designs including the well-known ADC-10, ADC-25 and XLM systems. They were all based on his "induced magnet principle", which was derived from the older GE variable compliance systems that were used as affordable magnetic pickups in the 1950s.Without him the record would certainly not have developed so rapidly. His designs have influenced all others significantly: from Audio Technica to Ortofon. The most famous "pirate copy" has managed to survive until today: The Nagaoka MP500 is based on his ingenious ADC 10E."

 

[MakeMineVinyl]

Also, with sufficient force the higher mass should have equal acceleration, right?

F=ma(2)

Except that the 'force' is coming from the stylus, which is moving the same, regardless of cartridge, I'd think.

 

[watchnerd]

No, just general vinylista stuff, but a little more evidence based than some.

Thanks for the link.

This guy is an even bigger 'objectivist vinyl dork' than me.

He's measured all the headshells I use:

AT: http://korfaudio.com/blog49
Jelco: http://korfaudio.com/blog53
SME: http://korfaudio.com/blog55

 

[MakeMineVinyl]

FWIW, I've been using a Micro Acoustics 630 since I bought it in the 80s or so. Consistently, I've found I like the sound of it better than various MC and MM cartridges I've owned over the years. The cartridge is extremely light since its basically a ceramic type. The picture by the way is not my TT - just grabbed it off the internet machine.

 

[watchnerd]

Except that the 'force' is coming from the stylus, which is moving the same, regardless of cartridge, I'd think.

I was thinking of the magnetic force as measured in Newtons.

Regardless, for the argument to have merit, it should show up in some measurement, like impulse response.

I know people say "lower mass" a lot, but I haven't seen any measurements that show it is relevant.

 

[watchnerd]

FWIW, I've been using a Micro Acoustics 630 since I bought it in the 80s or so.

You've been able to get replacement styli for that guy for 35+ years?

 

[MakeMineVinyl]

You've been able to get replacement styli for that guy for 35+ years?

The stylus to this day doesn't show any wear. I got it after 'perfect sound forever' became a thing and the TT got very little use, so its essentially new condition. Tracking at 1 gram probably helped with the longevity.

 

[MakeMineVinyl]

I was thinking of the magnetic force as measured in Newtons.

Regardless, for the argument to have merit, it should show up in some measurement, like impulse response.

I know people say "lower mass" a lot, but I haven't seen any measurements that show it is relevant.

From what I've seen, MC types are more likely to have a tipped-up high end, giving the impression of 'air', 'transparency' yada yada.

 

[watchnerd]

From what I've seen, MC types are more likely to have a tipped-up high end, giving the impression of 'air', 'transparency' yada yada.

The MP-500 seems the opposite of that based on the lab tests:

Although I can't hear that high. My hearing starts to roll off above 12k.

 

[Helicopter]

I love the Stanton/Pickering MI 'blob' cartriges with LPGear VividLine. Most of the others I have are MMs.

I don't have MCs. I will probably try Audio Technica OC9 XML MC cart or an SLC version next.

 

[MakeMineVinyl]

Speaking of which, do you or anybody else here know of a test record which has an extended length track of pink noise? The rest record I have (ultimate analog test disc) has some 'pink noise' but it doesn't seem accurate and is labelled for burning-in cartridges or something like that...