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drjjpdc
04-24-2010, 05:20 PM
I am considering a new TT rig. Are MC's better than MM's? Is there some output voltage that requires a head amp? How hard is it to match a head amp to a low output MC to keep hum and hiss to a minimum?

1KW
04-24-2010, 05:21 PM
I'm considering the blackbird as my first MC cartridge. Anyone have or heard one ?
Mike Fremer gave it a good review.http://audioaficionado.org/attachments/turntables/5809d1272144291-moving-coil-moving-magnet-asumblkbrd.jpg

1KW
04-24-2010, 05:28 PM
The Blackbird is a high output MC cartridge ie 2.5 mv so you can use a standard MM phono pre amp. . The advantage is supposed to be lower noise ie higher signal to noise ratio without the need for a additional amplification stage which theoretically could introduce more distortion.

schaefer11
04-24-2010, 06:51 PM
My experience from back in the "old days" was that MC cartridges were considered superior due to their "airy" high end. But that was because the high end was tilted up in most MC cartridges. I don't think the technology is what matters as much as finding a cartridge with the smoothest sounding frequency response to your ears.

Removed
04-24-2010, 09:25 PM
I am considering a new TT rig. Are MC's better than MM's? Is there some output voltage that requires a head amp? How hard is it to match a head amp to a low output MC to keep hum and hiss to a minimum?

MM cartridges have a small magnet mounted to the cantilever which moves between (two) coils of wire inside the cartridge body to generate the signal. The average output is somewhere between 2.5mV and 5.0mV into a 47K ohm load and requires approx. 40dB - 50dB of gain from the phono stage.

MM are less money to manufacture due to how thier constructed and the stylus is easy to replace since the magnet is connected to the cantilever and not to anything inside the cartrdge body itself, however being that there is more weight at the stylus/cantiver end this can effect how it responds to the record groove vibrations (less information being retreived)

MC cartridges use tiny coils of wire, they are attatched to the cantilever and moves between the magnets to generate thier signal. MC cartridges come in three versions Lo, Med and Hi with the Lo version having a output of .01mV - .05mV, Med output .08mV - 1.5mV and Hi output having 2.0mV - 2.5mV.

Gain required for Lo output cartridges are typically 55dB - 75dB, Med output require 45dB - 60dB and Hi output cartridges require 40dB - 50dB of gain.

Typically you load a MC cartridge by taking the input impedance and multiplying it by a factor of (ten) so if the input impedance is 20 and you times it by 10 then your loading should be around 200 ohms or there abouts, this is a good place to start but further experimentation is advised to achieve the best results for your listening preferences and the manufacture will spec there recommendations but try different loading options :yes:

Lo output MC have the lightest coils on the cantilever end which allows the Lo output cartridges to be nimble and the fastest in retrieving the information from the groove as with Med and Hi output MC there is a bit more weight on the cantilever which makes them not quite as nimble and fast as the Lo outputs cartridges but still retain the speed as compared to MM type cartridges which are a bit slower and less detailed, less finess and may seem rolled off a tad compared to the very best MC types and this shouldn't discourage you from using MM types! its really a personal preference thing here for sure.

To sum things up its going to come down to your budget as to which to choose but IMO if your leaning towards a MC then I would first square away your phono stage and build from there.....If you choose to go with MM then things are a bit easier but still the phono stage is important, the phono stage sort of dictates which group of cartridges your needing to look at (phono stages come in many flavers in regards to gain and loading options) another factor that comes into play is the cartridge/tonearm matching (resonant frequency) we have some great tools on line to help out with this........all in all you have many choices in both MM and MC and you can achieve great sound with both :yes::yes:

Jeff

Mark J
04-25-2010, 12:35 PM
There are many phono preamps that will handle MC or MM cartridges. As you have probably learned the HOMC will plug directly into the MM cartridge phono input. But if you need the LOMC amplification, you can find it in these phono preamps available for 150 and up.

I notice your KD-600 has the SME III bolted to it. This tonearm is an extremely low mass arm and requires the type of compliance found mostly in MM cartridges. Since that statement might not make any sense, Howard makes it easy to understand, for a low mass arm look for a cartridge that requires very low tracking force. This means the Shure, Audio Technica and others will work well with that arm. Almost all MC cartridges need more mass to work best. I have a Fidelity Research arm with a mass of over 30 grams. It really likes the Koetsu cartridge installed.

That paragraph is about matching compliance to tonearm mass to get a system resonance in the 'safe' zone, about 8-12 Hz, above record warp and below very low bass. The cartridge database has info on this. You can find that on vinylengine.com to learn more, or just ask.

two dot
04-25-2010, 02:07 PM
David,

I have the Blackbird on my LINN LP-12 and absolutely love it. Could not be happier.

In fact, this whole combo could be perfect for you.

Classic, timeless, warm, sweet, high quality, the reference for years, can be bought well, good resale, sound perfect for you.

PM me.





I'm considering the blackbird as my first MC cartridge. Anyone have or heard one ?
Mike Fremer gave it a good review.http://audioaficionado.org/attachments/turntables/5809d1272144291-moving-coil-moving-magnet-asumblkbrd.jpg

drjjpdc
04-25-2010, 11:03 PM
Well my rig is about 25 years old and I may be getting a new one. I am leaning toward the Clearaudio Concept and using my VDH as a starting point. After that the leading candidates might be a Benz or a Dynavector. I really like pipe organ, so something that has some bass is a must. Denon and a Grado are also possibilities. I would like to keep the cart price less than that of the TT.