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
Raoul,

Yes...  I confirmed the results via measurement.  I did not put forth any listening impressions.

To be clear the stage that Lew M is using is not a current amp in the true definition of the term.  Its circa 20Ω input Z is multiples enough of his cartridge internal impedance that it acts as a traditional voltage amplification stage.
Dear @intactaudio  : Thank's for the clarification I understand it in diferent way.

At the end through measurements or listening tests seems to me that only you, PM, JC, Palmer and I " experienced " that loading subject and its effects, at least according with the facts I have on hand.

Sorry @lewm  you was rigth.

R.
For the record, I did mention the relationship between the input impedance of the Intactaudio device and the output Z of my MC2000 (2 ohms into 20 ohms), by way of speculating on how it is working with that particular cartridge. Nearly any very LOMC cartridge with a very low internal R would tend to work with the IA device in a voltage-dependent manner, I guess.  Still, the IA device also sounds great with one of my other LOMCs that has a high-ish internal R and where the amplification would be more in the current domain.  (Dynavector 17D3 which has internal R = 32 ohms.) Be that as it may, I am driven to try out a very very low input impedance phono some time, with the MC2000, just to satisfy further my curiosity.

Raul, When IA used the term "tests", he meant exactly that.  He made measurements using the proper test gear and said nothing about listening tests.  Not that there is anything "wrong" with either approach, except I would posit that subjective testing based only on listening is fraught with error, not the least of which is error due to listener bias.  Furthermore, Dave (IA) was not per se testing Atmasphere's hypothesis that low resistive loads impair HF tracking.  He was testing a finding put forth by Moncrieff, to the effect that unloaded LOMCs (i.e., with a 47K ohm load) exhibit a form of IM distortion (when he used one particular pair of frequencies for his IM test) and that the distortion is reduced when you use progressively lower resistive loads, down to 100 ohms. Nevertheless, Moncrieff's and Dave's measured findings might (or might not) provide a scientific rationale for your position.  As for me, I wonder about the particular pair of frequencies that Moncrieff used for the IM test and whether one might get a different result for other pairs of frequencies.  (I think the upper one was 4KHz; would that be high enough for the effect described by Atmasphere to kick in?) Or for different cartridges.  (I don't know what cartridge was used by either Moncrieff or Dave.)  Finally, I personally wouldn't care if using a 47K load produces a bit more measurable distortion, as long as the result sounded closer to live, real music compared to a 100R load.
Raul, Likewise, I wrote the above post before I saw your response to Dave.  No problemo.
Dear friends: Yesterday I mounted the Talisman LOMC cartridge that's an extraordinary performer and I did exaustive tests " plñaying " with load impedance and capacitance and no matters what and even that my system has very high resolution with every kind of distortions at minimum I can't detect/be aware of no single anomaly in the HF range and I put focus on that HF range. Nothing.

So with LOMC cartridges  current or voltage phono stages designs makes no diference in that  loading subject where that " limit trace " does not exist.

So and due that over 95% of the phono stages are voltage designs the important issue down there is the overall quality levels of the design and the quality levels of the excecution of that finished design on the market.

Btw, no one of the LOMC cartridges that I tested performs in a superior way when loaded at 47k, always inferior quality levels against lower loading values. My MM/MI I " historically " load it at 100K.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.