Clio, exactly. I posed that question to Jeff when we visited his shop last week. The Critereon is his soon-to-be-released "statement" preamp. It will be battery powered.
The Continuum 500 converts any AC to pure DC and the PC1 in front of his devices like the 501 monoblocks and the Capri does the same thing. My question was, "Is there an advantage of one DC over the other." His response that the Critereon is a low current device and he already had developed a reliable, long-life battery system, so he used that.
The 312 stereo power amp and the Continuum 500 have PFC built in. The separate PC1 unit allows many (most) of his other products to benefit from the same technology. It's clearly a plus on all his power amps that can use it, because it stabilizes the draw on the AC, which can be quite violent when not modulated somehow. With low current applications your benefit will vary, depending on the quality of your mains and some other factors.
I think that getting into pure DC can't hurt, because of the noise floor being lowered and all grounding issues just go flying out the window.
Guido, now that you've had more time with the Capri/PC1 combination, do you think it's a positive in that application in your system with the 312?
BTW, there's a blog about our Rowland Factory Tour, including some discussion of Rowland's philosophies, at
Soundings BlogDave