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MC loading at 47K

Hi All,

Just after some expert advice from your good selves if I may. My current system is as follows:

Musical Fidelity KW550 intergrated amp which has a MM and MC section, both loaded at 47K. The only difference between them is the step up voltage.

My turntable is the Rega P9 with Ortofon Kontrapunkt A.

Looking at changing my cartridge but honestly cant decide between MM or MC.

My music taste are as follows:

Reggae
Soul
Female Vocal
RNB

No classical or jazz.

So what should I choose based I'm only limited to a 47K loading. I was thinking either of the below:

1. Ortofon Jubilee (MC)
2. Ortofon 2M black (MM)
3. Clear Audio Maestro (MM)

Is there a down side to loading up a MC so much?

Thoughts please...thanks
che13

Showing 10 responses by stops

stops
56 posts
 
Lowering the load thins out the sound in an MC cartridge. It also narrows the stage width but it adds more definition.
stops
56 posts
 
I think you are getting confused with lowering the height of the arm. That does make the sound muddy.
stops
56 posts
 
I have the Benz Glider SM and have experimented with the loading using a Phonomena. FIRST of all I should mention that you should set the arm level or slightly lower at the back end and the playing weight correctly BEFORE you play with the loading. If you do not you end up trying to correct a VTA related issue with the cartridge loading!!!

The Benz spec sheet has a huge window from 200 ohms to 47K so obviously that is not much use. The 47K gives a lot of width but it falls down in complex passages of an orchestra you lose a lot of the individual instruments in a hodge-podge of sound. I ended up at 680 ohms. Lowering it beyond that thinned out the sound too much.
stops
56 posts
 
The coil in the cartridge is a generator and the external load will damp the generator bringing the mechanical movement (coil) to a quicker stop (back emf). This is analogous to the damping on a speaker by the LOWER output impedance of an amplifier.It is also apparent that a lower resistive load on the cartridge will reduce the output so if you do compare the effects of the various load resistors on the cartridge you should adjust the volume level.There will be an optimum damping for the cartridge that will prevent overshoot of a rapidly rising waveform and therefore trial and error is needed.

Any NON-Personal feedback is welcome.
stops
56 posts
 
Thanks for your scientific analysis
stops
56 posts
 
Audiofeil:I have done and you are NOT the last word on this subject even though you are trying to be by your soapbox statements....

Dopogue: I agree with you on that. I am using the Phonomena and the changes require extended listening to a wide variety of material. Other items that have a more obvious impact to sound are whether the arm is level or slightly lower at the back and/or the playing weight. These should be optimised BEFORE the load resistance into which the cartridge is fed is evaluated.
stops
56 posts
 
I know but apparently way over your head. You should just give up this line of work.
stops
56 posts
 
Here is a useful reference for those of you who want to get some facts on the loading of a MC cartridge.
http://www.extremephono.com/Loading.htm
stops
56 posts
 
Dan_ed: I have read the references you suggested,thanks. Is this different from the analysis of a critically damped tuned/ resonant circuit? I would imagine that the "loss" of energy in the sound with the reduction of the 47K load is the reduction of the resonant peak within the audio band around 10 -15Khz and quite common in MC cartridges. Surely a more accurate reproduction would be without this peak present? The earlier reference I posted shows the result of this in a real world cartridge.
stops
56 posts
 
It is refreshing to hear from sane personnel. I appreciate all the comments and suggestions. I will reiterate a point I made much earlier and that is -I found much greater differences in the sound from the VTA and playing weight than I did from adjusting the load resistance of the cartridge. So I suggest that adjustment be done first using a playing weight in the middle of the spec as per the manufacturer and a tone arm that is level.
Intuitively I would expect a critically damped cartridge to handle complex orchestral pieces better (faster recovery?). I do find that I can hear much more of the individual instruments in a complex passage with an optimum load.
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