Cartridge Loading- Low output M/C

2channel8 & Ericsch, it is true that the sonics of LOMCs themselves are essentially insensitive to reasonable amounts of load capacitance. However, note the statement by Lyra cartridge designer Jonathan Carr that I quoted early in this thread:

I should now debunk another myth regarding loading, which is that low-impedance MC cartridges are insensitive to capacitive loading. OK, the MC cartridges themselves aren’t particularly sensitive to capacitance, but the inductance of the cartridge coils will resonate with the distributed capacitance of the coils and the capacitance of the tonearm cable to create a high-frequency spike, and this spike certainly is sensitive to capacitance. In general, the less the capacitance the better. Having more capacitance (across the plus and minus cartridge outputs) will increase the magnitude of the high-frequency spike and lower its frequency, neither of which is good news for phono stage stability or phase response.

Generally speaking, the greater the capacitance across the plus and minus cartridge outputs, the heavier the resistive loading needs to be to control the resulting high-frequency spike. Conversely, less capacitance allows the resistive load on the cartridge to be reduced, which will benefit dynamic range, resolution and transient impact.

Also see the link Jonathan ("JCarr" at Audiogon) provided in his post in this thread dated 5-28-2018:

http://www.whatsbestforum.com/showthread.php?15077-Cartridge-Loading-A-Misnomer&p=258578&vie...

That is why Ralph (Atmasphere) stated above that "it is advantageous to keep the resonant frequency as high as possible."  It's all about the phono stage.

Regards,
-- Al

2channel8   6-1-2018
I haven't been able to measure my phono cable's capacitance. My multimeter just reads 0.0 F, even though it has a uF range. 

As a rough ballpark approximation, a typical phono cable may have a capacitance in the vicinity or 25 pF (picoFarads) per foot or so, corresponding to 125 pf for a five foot length.

125 pF is 0.000125 uF (microFarads), and 0.000000000125 F (Farads), so it would be understandable that your meter indicates 0.0 F.

Regards,
-- Al 

Specifically to phono cable from TT RCA box to phono stage.....Cable capacitance does matter with regard to LOMC cartridges. Lyra specifically suggests using a low cap cable, they do not recommend high cap cables. 
I also used a Morrow Audio PH6 Grand Reference phono cable for some time and when I finally asked Mike he said 390pF/mt and I was shocked! He said he never heard HF rolloff with his cables, I tend to agree but then I assume it is because you have to load at a lower setting, which is not good for the cantilever, you run the chance of stiffening the cantilever.

Once I switched to AQ Cougar at 40pF/mt and loaded my Delos to 475 ohms.That's when the higher dynamics and resolution came into play, it was a jaw dropping moment. The Delos performance rose many levels, really everything just got better.

On my Musical Surroundings Nova II I have the setting at 100pF (the new model settings are 100/200pF, the older were 200/300pF), Michael Yee changed it. In general I too hear no difference but have it set to lowest closest to my cable rating.

I tell everyone just find out all the specs you can, then go from there. You can't make the proper settings till you know all the info along the signal path. 

Cheers

Al, Thanks for bringing up the question of metering. I do own a Sencore LC meter that can measure down to the pF level. If I want to measure the capacitance of a cable, do I just place the Sencore probes on the hot and ground of the cable, with the other ends (hot and ground) unterminated? That seems right, but I am not sure.

I also think this might be a good place to summarize the points made by Ralph, Al, Wyn, etc.  First, no one is saying that there is only one correct load for a typical LOMC cartridge with very low internal resistance.  Second, I think Wyn has conceded that his first model for the behavior of such a cartridge when driving a phono stage was based on some usually false assumptions: (1) that such cartridges have coil inductance as high as 0.5mH, and (2) active RIAA correction in the phono circuit, which is atypical of most of the “best” phono stages capable of working well with such cartridges without a SUT.  Assuming inductance in the low micro Henry range and passive RIAA, we should keep associated capacitance as low as possible.  Under all these conditions, it is not inconceivable that a high resistive load, e.g., 47K ohms, might sound better than the more typical values of load resistance used by us audiophiles, e.g., 100R.  In my case, I can say that the difference between 100R load an 47K is not huge by any means, but once I had tried 47K for at least 2 or 3 of my LOMC cartridges, I’ve developed a preference for it.  What I hear is as predicted, highs seem more open and extended.

@catcher10, Why 475 Ohms? Why not 1000?
BTW, I have no report on 100K yet. Too much new digital music to listen to at the moment.