I just installed an old "The Head" stepup (precursor to the EAR MC-3) between my 0.6 mV Koetsu Red Standard and CAT Ultimate pre. Just a fantastic improvement with more dynamic and tuneful bass among many other things. This brought back what went missing from my analogue when I swapped out a Rowland Coherence One for the CAT last year.
If you have a lowish output MC and an all-tube phono stage (with a few exceptions) a stepup or head amp would likely be the way to go. This will likely "open up" the sound considerably, reduce any tube noise that the phono stage may generate, and allow you to keep the gain knob at roughly the same position for line and phono sources thereby avoiding nasty surprises when switching between sources.
I have no first-hand experience with the NuVista M3; I think it has a tube preamp section. Also, depending on how it is measured, I think the Ruby 2 cartridge output is closer to 0.3 mV. I suspect a stepup WILL give you what you are looking for. Go for something basic first and just remember to plug it into your MM (not MC) phono input.
If you have a lowish output MC and an all-tube phono stage (with a few exceptions) a stepup or head amp would likely be the way to go. This will likely "open up" the sound considerably, reduce any tube noise that the phono stage may generate, and allow you to keep the gain knob at roughly the same position for line and phono sources thereby avoiding nasty surprises when switching between sources.
I have no first-hand experience with the NuVista M3; I think it has a tube preamp section. Also, depending on how it is measured, I think the Ruby 2 cartridge output is closer to 0.3 mV. I suspect a stepup WILL give you what you are looking for. Go for something basic first and just remember to plug it into your MM (not MC) phono input.