Cartridge loading


Presently I am using a ZU/Denon DL103 mc cartridge with ZU Audio's highest tolerances.  I had this cartridge mounted on my VPI Prime and after going through all the various loading combinations, I settled on 200 ohms.  I was always satisfied with my choice of setting.  I no longer have the Prime and now use the Technics SL1200G turntable.  After having the same cartridge mounted and aligned by the dealer, I inserted it into my system and enjoyed the sound immensely, never touching the 200 ohm setting.

Yesterday I was listening to vinyl most of the day and for some reason I found the sound to be better than ever, mostly in the treble area.  The highs had shimmer when needed and I had played the same records many times before on the Prime and they never sounded as good as they did yesterday.  Just for the heck of it, I checked the cartridge loading and found it was now set at 1000 ohms.  As I said, when I put the Technics into the system, I never bothered changing the loading which was at 200 ohms as it was the same cartridge, just a different turntable.

I believe I know what happened, when I last used the tone controls on my McIntosh preamp, (you have to shuffle through a menu) I must have inadvertently put the cartridge loading at 1000 ohms.  It truly sounds fantastic, better than I ever thought possible.  The Bass is still very deep and taut, midrange is the same but the treble, oh my, so much better.  Now the million dollar question is why should it now sound better at 1000 ohms, when it sounded great before at 200 ohms?  Can the tonearm on the Technics have an effect on cartridge loading?  I always thought it was all dependent on the preamp, amp and speakers.  What am I missing here?  I am very curious to know.  The specs for my cartridge say greater than 50 ohms for loading.

Thanks
128x128stereo5
Dear @mijostyn : Almost always 100 ohms works really good even with phono stages with a low headroom ( but today designs comes with high headroom, no problem at all. ) PM is rigth and exist two " problems " as PM said at 100 ohms is not really dull but the sound sounds what is in the recording adding the less. That " open " sound reported for gentlemans loading at 47K like that kind of sprk and openess that are only added distortions for that cartridge loading value.

I always supported that kind of statement for many many years ( posted several times in this forum and with out know anything of PM comments. ). intactaudio is rigth about : ""   to compensate for deficiencies elsewhere in the system."""

The other issue is a bad phono stage design or a " terrible " TT/cartridge/tonearm set up or selection in between with wrong matchs.

@intactaudio  of course syntax's sytem is in trouble and that trouble comes from the phono stage design.

Btw, this is what we can read in the loading link you posted again:

""" 

As mentioned earlier, the peaking is best damped by lowering the load resistance. This is why MC cartridge manufacturers often request loading of about 100 ohms. The next plot shows the 5mH 10 ohm cartridge loaded with 200pF and a variable resistance. Note the 4.7k loading provides very effective damping while maintaining a bandwidth of over 100kHz. Too much damping with the 470 ohm load pulls the response down too quickly. Most MC cartridges have less inductance than this example (chosen to highlight the issue), and so the typical loading value of 100 ohms is usually quite reasonable. """


and something important is that the inverse RIAA eq. was not take in count for the calculations and the site disclosed it.


As syntax said loadin and MC always be an often asking subject because loading function as a " tone control " but the culprit or comes for a bad PH stage design or from each one of us ears and our knowledge levels about how the live MUSIC sounds and of course our preferences on what we like to hear.


Btw, I don't know you or intactaudio but I'm still waiting for the @atmasphere  precise answer/numbers on that high frequency lower cartridge tracking because the loading issue along that stiffen cantilever for it. I'm sure he will comes for.


Regards and enjoy the MUSIC NOT DISTORTIONS,

R.




Mijostyn,

The Hagerman site gives loading examples for what appear to be a typical MM cartridge where the resonances being damped are just outside the audio band.  This discussion has been about MC cartridges where the resonance in question is typically above 1 megahertz which is a very different situation.  The typical MC cartridge has around 1/1000th the inductance of an MM so enter 0.005 into the mH field of the calculator to see what we are discussing.  

I for one would love to see documentation of the ability of a cartridge to generate a 1MHz signal to excite this resonance.

dave
I think it’s analogous to “back EMF” that affects the interface between amplifier and electromagnetic speakers. The movement of the coil on the cantilever that is excited by the groove is not perfectly damped. Any spurious motion thus created would generate a voltage. The load resistor affects the degree to which the spurious motion of cantilever is damped out. Why is it hard to imagine that the damping force makes the cantilever also do more work?
But I’m just guessing pending an opinion fro Ralph or Dave.
I just read this review and thought of Ralph's comments:

http://www.10audio.com/aurorasound_VIDA_Prima.htm

Just being curious, I unloaded the Madake by switching the loading to 47k Ohms. WOW! The upper frequencies opened up and became noticeably clearer and with finer resolution. Update to my advice above, start your tests for the optimum loading setting with the MM (47k) settings.

The VIDA Prima and Pass XP-25 share an important attribute: they both sound best when the Miyajima cartridge is loaded at 47k Ohms. This suggests circuits that are designed to manage a MC cartridges’ tendency to sound better loaded, a weakness we refer to as “ringing”. Some of this artifact could be an issue with the phono preamplifier. The VIDA Prima does not seem to have any tendency to exacerbate ringing.