Playing with Cartirdge loading on my phono stage

The bottom line is you cannot hurt anything by experimenting with a wide range of different loads and selecting the one you like best. You could even start at 47K ohms and go down from there in logarithmic steps. But it is probably wise not to go lower than the manufacturers lowest recommendation. Ideally, you want to maintain a 1 to 10 ratio between the internal resistance of your cartridge and the load resistance.

I have been surprised that sometimes loading makes virtually no difference and then on some cartridges it makes a small difference. Surprisingly to me I have never gone: “something sounds wrong” and traced it to accidentally changing loading. 
 

You just have to flip through them. 

I recently acquired a Sumiko Starling and between 100 ohms and 200 ohms there is a HUGE difference. With Lyra Kleos, a 100ohms difference is hardly noticeable. Just play with it. Don't listen to anyone about that but your ears.

In general, higher ohms mean leaner sound and better tracking. My phono does 10R to 47K, and I usually run the Koetsu at about 1k. But there are times when I prefer it at 30R, or even 47K. Depends on source, mood, and how long the electronics have been warming up.

Tuning by ear is the way to go here, as others have said. 10x the internal resistance of the cartridge puts you on the edge of pinching the signal - that is decreasing the volume by resistance instead decreasing it by lowering the gain. Once you get down to 5x, this is noticeable. Downstream volume pots can be opened up if you pinch the signal at the phono pre, which may be preferable. I’ve always thought most systems have too much gain. Some carts I have (Miyajima Zero and Denon 103R) sound better to me when pinched at the phono pre. Some (Hana) are the opposite and sound better opened up.  The differences are subtle and in my system come down to bloom vs transients - or to say it another way - fullness of the instruments vs separation of the instruments. When the resistance is pinched, tones fill up with more bloom. When opened up, instruments have more space between them. I’ve tried recording A/B to DSD and then compared playback - that didn’t work. Best to work from a recording you are very familiar with.