Cartridge Loading for a phono pre amp


Hello,

I have recently acquired a phono pre amp recommended by Michael Fremer.  It is “THE VINYL”, from QHW audio, Spain.  It got a great review.  I have a Benz Micro Glider rated at 1.1MV.  I have no idea how to set the dip switches for MC Load impedance for this cartridge. The options I have are as follows: 47K, 1K, 560R, 470R, 100R, and 47R.  I have a solid state amp and pre-amp, and also have a sub that I use, rarely.

Any advice would be most appreciated!!

judsauce

@holmz : As  ​​​​​@imhififan I did my tests in specific for resonance and tracking against load changes. Btw, thank's for your answer .

 

Differences in sound with load changes depends of the active high gain phono stage characteristics and your brain perception about. LOMC cartridges are " non " sensitive to load impedance changes.

R.

Dear @imhififan :  " Although theoretically loading..... and 100Ω loading made the cartridge work 470 times harder than 47kΩ loading. ..............., I think the effect on the cantilever stiffness is insignificant. Therefore the test result show no difference. "

 

Rigth and was proved in other thread:

 

" certainly not on tracking which is demonstrably false based on IM tests on tracking performance that I have incidentally performed as a function of load. While mechanical impact does occur as a result of electrical load- there is some back emf necessarily generated by the signal current that affects the mechanical motion, but a quick back of the envelope calculation using Lenz’s law and the 10uH cartridge suggests a 2 orders of magnitude difference between the generated signal and the back EMF for a 100 ohm load at 20kHz- certainly not enough to cause tracking issues . By the way, I constructed a model for the cartridge back EMF using Lenz’s law and incorporated it into my simulations.
For those who are interested, the simplest version of the law is V(t)= -LdI/dt.
In this case the parameters can be measured (the LC100A meter from Ebay is a great way to do it) and the back EMF acts to oppose the voltage developed in the coil. The fractional change (attenuation) in the signal voltage is easy to calculate as it approx. equal to -L*2*pi*frequency of interest/Rload. So, it’s inversely proportional to the load R and proportional to the frequency. "

 

R.

While mechanical impact does occur as a result of electrical load- there is some back emf necessarily generated by the signal current that affects the mechanical motion, but a quick back of the envelope calculation using Lenz’s law and the 10uH cartridge suggests a 2 orders of magnitude difference between the generated signal and the back EMF for a 100 ohm load at 20kHz- certainly not enough to cause tracking issues .

This statement does not support Raul's assertion: it says something quite different!

Dear @imhififan  : Thank's again for your advise. The answer to the main subjects in this and other threads ( elsewhere ) where just in front of me and never seen it,. Go figure ! Nothing like those first hand tests 

 

Good ! !

 

R.