Jump to content

The difference between Moving Magnet / Moving Coil / Moving Iron Cartridges


MicroMara

Recommended Posts

  • 2 weeks later...

Now, after much about TT`s , cartridges and Phono-Preamplifier was reported it´s now about the optimal capacity values for MM / MI  and MC pickups.

 

MM Cartridge / MI Cartridge

In an MM system we do not need to worry about the terminating resistor. MM inputs are always terminated with 47 KOhm. There is nothing for you to do. A MM system can react sensitively to a completely wrong capacitance value of the connected cable. Here the complete cabling counts - starting with the small plugs at the pickup to the RCA plugs and everything in between anyway. The sum of all capacities is decisive .A value of 150pF is considered optimal and at the same time maximum. Real tonearm cables therefore usually have very low capacitance values.

 

As long as the overall result remains below 150pF, you will find that everything is fine in terms of sound. If you want, you can adjust this value exactly, but you should not expect too much from it. However, if you are running an MM system and you have the impression that it runs far away from its sonic capabilities, you should have the cable measured or have a look at the technical data. Maybe the capacity of the cable is too high after all and maybe this is the reason for a not so great sound.

 

MC cartridge
With the MC system, the requirements are reversed. Here the capacity value is not important. The correct terminating resistor is all the more important. If it is not correct, this may have an effect on the volume (one pickup more with the next less), as well as on the electrical damping of the needle carrier and thus on the overall sound.If an MC pickup is finished with a too low value, its sound image looks "more tired" - but it gains spatial depth. If an MC pickup is terminated with a too high value, it sounds "thinner", "harsher" and simply "nervous".

 

The value from when this resistance is "much too high" depends on the pickup's own internal resistance. With some pickups 300 ohms is already enough - with others you have to go to over 2,000 ohms. From this value nothing changes in sound. So whether we use 2,000, 20,000 or the 47,000 ohms of the MM input is completely irrelevant. In the technical data of the pickups there is usually an exact value given, which you should keep to. Otherwise, just experiment a little.

 

Can I measure the capacitance of the cable myself?

 

It is easier than to measure by looking at the technical data of the cable. If they are below 100 pF/m and the cable is not longer than 39,37 ", you do not need to worry.
However, if you have a suitable measuring device and know how to use it, measuring is no magic trick either. Just remember to take off the shoes on the pickup before measuring.

 

 

 

 

 

 

  • Like 2
Link to comment
Share on other sites

  • 1 month later...

This thread is really helpful and MicroMara, your information is very useful.

In the past couple of days, I've been researching in order to upgrade my vinyl spinning to a next level. I first thought the best and obvious thing to do was to replace my €44 phono preamp with a better one, eg the iFi Zen Phono. But then, I read on many places that it would be smarter to upgrade the pickup needle. After all, after the record/album, this is the first 'device' in the audio chain, and any fault here (hiss, rumble etc), only will be magnified in preamp and amp etc rather than corrected.

So in my case, I am now considering upgrading my Ortofon OM10 to the OM20. The OM10 is €49, the OM20 is €179 (or €155 on Amazon). Is it worth the investment? I was hesitating a lot: the pictures show no difference at all, except for the number printed on it. Is a tiny piece of junk really worth €179 I thought?

Now the plot thickens: compare these pictures, which I found on a large website selling pickup needles:

OM10

image.png.8e96dd8a0f47ce40cc425291eeab4fa2.png

OM20

image.png.174120b3befcb1ee37bdfed05a1a1b0e.png

 

Can you tell the difference? Only when I came across a picture posted at Amazon.de in a user review, I understood what the difference really was:

image.png.1a6fb079a0c0c9550539cf1994b63f4c.png

You can see that the diamond of the Stylus 20 is much smaller, and to quote the original user review: "Both needles have an elliptical cut, but the 10 has diamond chips mounted on the needle in metal ring,  while the 20 has a bare diamond mounted on the needle directly." This must explain the upgrade in sound quality. My point is that it took half a day to find out that some websites would just use a mixed bag of pictures, or low rez pictures that would hardly demonstrate the differences between these needles...

 

Now take a look at these pictures of the 10 and the 20, which are from the official Ortofon website:

https://www.ortofon.com/media/14679/10-bottom.jpg

10-bottom.jpg

"https://www.ortofon.com/media/14681/20-bottom.jpg

20-bottom.jpg

The top picture is the 10, the latter is the 20... You must agree that they used the SAME picture... Likely a mess up of the webmaster of the official Ortofon website (!), or carelessness... If you're selling tiny things like a pickup needle for big bucks, I say you'd better get the pictures right...

 

 

  • Like 2
Link to comment
Share on other sites

You must make sure that the housing of the replacement needle has the red marking of Ortofon. If this is not present it is a replica, so it is not original. The OM 10 has an elliptical grinded diamond glued on, the replacement needle of the OM 20 is also elliptical naked grinded diamond which is incorporated into the cantilever.The needle compilation of the OM 20 is 30 nM, that of the OM 10 is 25 nM. So you´re right in your statement.

 

But I would consider a Ortofon 2M Blue for approx. 190 € , which will be a real step in a better sound class.

 

t_2m_blue_20200710191456.jpg.c0277beaabf0033f82d5e89f2eaae323.jpg

A very good MM system from Ortofon with outstanding sound characteristics. Dynamic sound, good sampling behavior, neutral sound image, detailed reproduction.
Easy installation, universally mountable on all light to medium tonearms. This system can be used perfectly in new and also in older turntables.

 

If you don´t wat to spend so much , have a deeper look on the 2M Red , approx. 98 €

 

t_2m_red_20200710191456.jpg.c05bbae81c9d1fb408968b2e674cb3dd.jpg

 

Inexpensive, but very good MM system from Ortofon. Dynamic sound, good sampling behavior and a neutral sound image. Easy installation, universally mountable on all light to medium tonearms. This system is best used in new and equally in older turntables.

 

 

 

 

 

 

 

 

Link to comment
Share on other sites

30 minutes ago, MicroMara said:

You must make sure that the housing of the replacement needle has the red marking of Ortofon. If this is not present it is a replica, so it is not original.

 

Now you really got me reluctant to do this upgrade... Here is a screenshot from a website I will not post the link:

image.png.191eb0e85bd5aa7e0c00a96621b448c6.png

 

And then, you get this rather bizarre explanation:

"Original needles: a "original" needle is a needle produced by the (OEM) manufacturer. This can be another manufacturer then the make of the needle. Examples are: some Dual needles are made by ortofon, some Sony needles are made by Audio Technica. original needles may come in a "standard" box, and not in the manufacturers box, this can happen because we buy these needles in bulk (without packing on a tray) and pack them in our standard box. We will never sell a copy needle as an original one!"

 

Yet, nowhere is explained what a 'replacement needle' is... Is it a 'copy needle'? To me, it sounds like an excuse to sell replicas and forgery...

 

This is a screenshot from amazon.de: also here, they use the picture that is also used for the Stylus 10... while again, they at least seem to be the official ortofon shop for Europe on amazon.de

image.thumb.png.aef921665ea711a3f08cc42d387206a1.png

 

 

 

 

Link to comment
Share on other sites

39 minutes ago, MicroMara said:

But I would consider a Ortofon 2M Blue for approx. 190 € , which will be a real step in a better sound class.

 

I think, but I'm not sure, that I cannot mount the 2M Blue on my OM cartridge/arm (Pro-ject Essential III with OM10).

I've read elsewhere that the 2M Blue and the OM20 (or was it OM30?) are comparable as for sound quality.

Link to comment
Share on other sites

There is a free market for the reproduction of needles and housings for many brand manufacturers e.g. from Switzerland. . This is legal. However, these usually cost only 1/3 of the price of an original needle from the corresponding manufacturer. The replicas match the original specifications of the manufacturer. Are therefore possibly as a "low budget" alternative to consider.

Link to comment
Share on other sites

59 minutes ago, ILI_MeloManiac said:

 

I think, but I'm not sure, that I cannot mount the 2M Blue on my OM cartridge/arm (Pro-ject Essential III with OM10).

I've read elsewhere that the 2M Blue and the OM20 (or was it OM30?) are comparable as for sound quality.

The tonearm is an 8.6-inch arm with gimbal bearing - known from the Pro-Ject Debut turntables.

 

As cartridges are avaiable different MM pick-ups: like the Ortofon OM10 (balanced sound, very inexpensive) or an Ortofon 2M Red / Blue . Both MM cartridges cut a good figure; the Ortofon OM10 does not sound as well resolving as the "big" 2M Red / Blue , but harmonizes very well overall with the Pro-Ject Essential and offers especially vinyl beginners a convincing sound experience. The somewhat more expensive Ortofon 2M Red/ Blue  sampling system offers better dynamics and livelier sound with better sampling behavior.

 

Link to comment
Share on other sites

Has anyone done a bake off with MM MC on same turntables running into same pre amp etc ?

 

Is there a frequency sweep record out there that could be used to run a trace from 20hz to 20khz ?

 

Compare someone reading a book like Richard Burton, which cart sounds natural ?

 

Must be a vinyl version of this somewhere.

https://www.amazon.com/Contemporary-Communications-PTS-CD-Precision-Signals/dp/B002WKQ5CI/ref=pd_lpo_15_img_0/134-7883024-9625440?_encoding=UTF8&pd_rd_i=B002WKQ5CI&pd_rd_r=e445cb3c-b3dc-42b5-ad9f-9df6260a1a7f&pd_rd_w=dTeKb&pd_rd_wg=fmgnC&pf_rd_p=7b36d496-f366-4631-94d3-61b87b52511b&pf_rd_r=GGRGC9D0RT6FMK4RBRXJ&psc=1&refRID=GGRGC9D0RT6FMK4RBRXJ

 

Vinyl engine thread on testing

https://www.vinylengine.com/turntable_forum/viewtopic.php?t=42481

 

Discogs test vinyl list

https://www.discogs.com/search/?q=3150+Hz&type=all&style_exact=Technical&format_exact=Vinyl

 

Tracklist

A01 1kHz Reference Tone (Mono)  
A02 1kHz Reference Level (Left Only)  
A03 1kHz Reference Level (Right Only)  
A04 1kHz Reference Tone (-20dB)  
A05 10kHz Reference Tone (-20dB)  
A06 1kHz - 20kHz Sweep (-20dB)  
A07 1kHz - 20Hz Sweep (0VU)  
A08 100Hz Reference Tone (0VU)  
A09 VTA Adjust  
A10 Standard Wow & Flutter Test (3150Hz)  
B01 Anti-Skate Test (315Hz, Sweep 0dB - +12dB)  
B02 Pink Noise (Lateral)  
B03 Pink Noise (Vertical)  
B04 1kHz Reference Level (Out-of-phase)  
B05 1kHz - 10Hz Sweep (-20dB)  
B06 Silent Groove

https://www.discogs.com/Analogue-Productions-Ultimate-Analogue-Test-LP/release/3525012

  • Thanks 1
Link to comment
Share on other sites

  • 2 weeks later...

This is Michael Fremer (analogplanet.com) who visits the Rega factory. Starting at 19:35, there is some very interesting footage of the team winding coils on MC needles, with interesting microscopic movies. A real eye opener that explains why good needles cost a lot of money...

 

  • Like 1
Link to comment
Share on other sites

  • 3 weeks later...

TT Tonearm Sound Improvement with a Headshell / Cartridge Isolation Damper  / Spacer . Design / Material: Mahogany wood

 

Today I experimented with a mahogany wood plate to listen if it would improve the sound of my TT. I was very skeptical. Hold such things actually for voodoo. The more I was surprised to find the following sound improvements. This Mahagony wood plate accessory is mounted in between headshell and catridge body...

* reduce the vibrations

* reduce the treble distortion

* bass coherence will be drastically improved
* midrange frequency gets more vivid colour than before
* whole sound is more musical and "warm"

 

There are different sizes and materials available . I really can recommend such little investment for a real listenable TT sound.improvement. It works only with TT´S which have the option for the Vertical Tracking Angle adjustment ( VTA ) , as the mahagony wood plate has a hight of 3 mm.

 

Soundimporvementkleiner.thumb.jpg.e644a6fd8670a251766aac40bfcf4502.jpg

 

Here are the different available models

 

614820190_SoundimprovementTT.jpg.ef05fecd152ffa1ec1de8bdd559204f8.jpg

 

 

  • Like 3
Link to comment
Share on other sites

Not new to me 

I have used and still use a plastic cartridge divider ( they are the thickness of copy paper ) 

Back in the seventies they were used as a gasket between cartridge and head-shell 

I think Stanton supplied them as part of the cartridge kit 

 

My view is that something soft in between 2 solid objects will mitigate any vibrations or sound waves 

So In saying that - paper or cardboard even automotive gasket will be just as affective 

 

 

  • Like 1
Link to comment
Share on other sites

On 1/28/2021 at 1:15 AM, Full Range said:

Not new to me 

I have used and still use a plastic cartridge divider ( they are the thickness of copy paper ) 

Back in the seventies they were used as a gasket between cartridge and head-shell 

I think Stanton supplied them as part of the cartridge kit 

 

My view is that something soft in between 2 solid objects will mitigate any vibrations or sound waves 

So In saying that - paper or cardboard even automotive gasket will be just as affective 

 

 

Why haven´t you told me that earlier my vinyl bro ????? smilie_op_006.gif

  • Thanks 1
Link to comment
Share on other sites

1 hour ago, MicroMara said:

Why haven´t you told me that earlier my vinyl bro ????? smilie_op_006.gif


If I knew I would have told you 

Would you be willing to conduct an experiment ?? to see if wood is the same / better / worse than automotive gasket material 

 

You have the wood divider to use as a template 😎 

Link to comment
Share on other sites

I just purchased a USB microscope x 1600 magnification 

Also purchased a lightning to USB connector so I can run it off my iPad / iPhone 📲 

 

I want to see what the condition of the stylus in my many cartridges 

Lets hope it works as I have planned on the iPad 

If not I can connect it direct to the computer 

 

 

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...