By One Box, I am referring to an internal power supply.
At this point, I have a two stage circuit, capable of MM gain and then when MC step-ups are added, you have MC gain levels.
I can also design the first stage to provide MC gain without step-ups and there is a bit more noise. However, that input is too hot for MM inputs and then there is a separate MM input circuit required. It makes more sense to use MC step-ups for MC, and MM without, with circuit gain designed for appropriate MM levels.
It would be less costly to simply offer a MM only phono stage, but that is not what people want. When a step-up is offered separately, it is typically quite expensive and may use the very best step-ups available.
The Lundahl step-ups are used in our PH 150 and they sound exceptional.
So now the only decision is if the power supply will be external or not. Also, if it is external, whether it will be two 1/2 width enclosures or a full width phono enclosure and a 'brick' style PS enclosure, housing only the transformer and noisy elements on a long umbilical, to be tucked out of the way.
Thanks,
Dan