Oy. Now you went and got me started, Doug. :-)
The site that Doug refers to says the "load" should be "within 100 ohm for a head amp" and "within 20 ohm for a step-up" (for both 501MkII AND 901)
There are few things with this information that have never been explained to my satisfaction (not to mention conflicting load figures on at least two other sites).
First, does "within" mean not above? Not below? Or, is it merely a poorly translated way of saying "about"?
Second, what is exactly meant by step-up? I have a phono stage that has a step-up wired directly in an MC section, internal to the unit. Is that considered a step-up? It isn't in the normal sense of, say, running a step-up trannie through the MM section of a preamp.
Third, I do not know if "within 20 ohm for a step-up" is actually referring to load or whether it refers to the upper limit of the "static" impedance of the transformer, not the load impedance.
I will say this. I load my 501MkII at 100 ohm and it sounds great. That said, I have found certain LP's that sound much more dynamic loading at 300 ohm (which I can do with a flip of the switch). I cannot go below 100 ohm (unless I want to do some soldering) so I do not know if I am missing out on something better. My guess is that if you load at 100 ohm you will be thrilled in most all circumstances. Whether small changes will result in big improvements probably depends upon your ear and your equipment.
