loading impedance

I have a zyx r1000 cartridge, per the manufacture's web page, the recommended load is >100 ohms ( I would think there should be a exact # that the phono section should be set to). The preamp that I have is adjustable (with some effort). What should the impedance be set in the phono section? I have heard some complicated methods of checking impedance of cartridge etc. How does it affect sonic characteristics if I were to change from a 600ohm to 100ohm resister?

I own this cartridge. It's on a JMW 12.5 arm on a VPI TNT Mk. 5. I use the Pass Aleph Ono phonopre.

What worked best for me were loads between 249 and 475 (Ono switch sets). I finally settled for 322.03. These are by no means the standard, it's a matter of long trial and error but, in the end, it pays off.

Best regards.
You have to take into account the electrical characteristics of the tonearm cable and interconnects used when setting the loading characteristics inside the phono stage. As Vvrinc stated, this may take some trial and error testing to see what works best in your system. Sean
I can test the phono section for different impedance but with some difficulty. I have to purchase resistors and unscrew two screws in the back and put new ones in, unfortunately there is no easy dial like some phono sections. will the trial and error be totally the sonics of normal album play? Having not done this yet what can I expect from different resisters? The preamp/phono section is a atmasphere mp1 and the turntable is a walker, possibly the brands names can lend more information. thanks for taking the time to help out.
I own that Cartridge too. I use it with 47kohms. I tried some other ( lower ) settings and it became dull and slow.
And I lost information then. But I can imagine, this can can vary from System to System.
Sean and Thomas,

Thanks for the tips. I did the impedance settings when my Z1000 was brand new. Out of laziness, I didn't fuss with the Ono's settings. For a couple of days now, I have tried 47kohms (a bit too bright in my system) and 1000ohms (seems so far to offer what Thomas had mentioend in his post without the brightness.)

Eralff, if your cartridge is a new one, waiting a bit for the final impedance decision may be necessary. Mine is about 100 hrs. old. In another 50-or-so hrs. I'll give 47k another go.

Best regards.
In general, As you increase the resistance of the resistor you will get stronger high frequencies. The secrect is finding the value between too dull and too bright.

Radio Shack sells (or at least used to) an assortment of 1/4 watt resistors that should give you all the values you need. Once you find the value you like you can replace them with audiophile resistors if you wish.
Dear friend: The ideal is that with the correct load impedance the frecuency response of the cartridge will be flat, but you need some tools and instrument to do that. So, if you are experienced in live music then you have to trust in you ears: take 3-4 records that are your standard and that you know extremly well and try differents impedance values till you are satisfied. Remember that the impedance ( in phono cartridges ) function like an equalizer. Be carefully.
Best regards.