cartridge loading


I am running a grado red with a project se II tube phono preamp. It is a mm cart that works on the tube box factory setting which I believe is 47kohm. I am getting some annoying hum and am wondering if any other settings on the tube box would be better. There are DIP switches that can be set for both mm or mc loading.
fromunda
Make yourself a couple alligator clip wires about 1 meter each. Clips on both ends of the wire. Clip one from table to preamp. Then clip the other from Phono to turntable and switch them around to see which reduces the hum the most. You may even try the preamp chassis or wall screw in the middle of the wall plug. One of those combinations most likely will work and reduce hum 50% to near 100%. In some cases you would have to turn your volume up past 12 o clock to hear noise. If you don't hear any noise as your average point then you have achieved your goal. Sometimes if you have a suspended table attach the ground to it with success. Make sure it hangs loosely. Oh you don't need a heavy wire at all. Just good old copper wire will do. Good Luck!
If you have a Rega, the motor can be grounded to eliminate the so-called 'Grado hum'. A wire, which can be soldered to the body of the motor, is simply run to the base of the tone arm. This sorts out the hum; no idea why Rega does not install the wire.

At any rate, don't bother with loading until you deal with the hum. After that, try about 22,000 ohms for a cartridge load and see what you think :)
thanks Atmasphere. Which setting would be 22,000 ohms? My manual lists for MM loading as such; 47kOhms/120pF
47kOhms/220pF
47kOhms/340pF
47kOhms/440pF
By the way what is pF?
Dear Fromunda: You have to try almost all those settings in your phono stage to achieve the best quality performance in your system.

MM/MI cartridges needs not only 47K ( some times different impedance value. ) but a capacitance load ( those pF you are asking for. ), these kind of cartridges are sensitive to capacitance loading.

Rgeards and enjoy the music,
Raul.