Mark, You wrote, "My pre-amp is a Mcintosh C220 and it has about 64 db of gain, would this be enough for the Black? and if so what would kind of step up would be a good idea?"
There is an internal contradiction in your question. If the gain of the C220 is sufficient, then you won't need any SUT at all. That's the ideal situation. If you're C220 really has 64db of phono gain, I would venture to guess that it WILL be sufficient for the Koetsu Black. I know nothing about the C220, but ideally you may want also to be able to reduce the phono load resistance from the standard 47K ohms to something like 100R to 200R for optimal performance, but it's a matter of personal judgement; the Koetsu will certainly "work" into a 47K load but may sound a tad bright.
There is an internal contradiction in your question. If the gain of the C220 is sufficient, then you won't need any SUT at all. That's the ideal situation. If you're C220 really has 64db of phono gain, I would venture to guess that it WILL be sufficient for the Koetsu Black. I know nothing about the C220, but ideally you may want also to be able to reduce the phono load resistance from the standard 47K ohms to something like 100R to 200R for optimal performance, but it's a matter of personal judgement; the Koetsu will certainly "work" into a 47K load but may sound a tad bright.