schoeps, as non-electret condensors, require polarization voltage. all DPAs, small and large, are permanently polarized at several hundred volts
the solutions that provide full 60V to the schoeps caps for polarization voltage are small-ish (naiant ipa, pip squeak, tiny box, and baby nbox in that order of size)
CMRs use a lower voltage source (4-10V) to provide voltage on a third wire to the active mic body which turns it into (reportedly) 40V polarization voltage which runs the cap at a 3-4 dB less sensitivity than a 60V solution like n-bobs, cmc6, kc5, vms02IB, etc.
advantages of CMR:
-uses less power than 60V polarization solutions
-simpler tech, easy to build your own battery box, circuit is literally battery, capacitor,and resistor, less than $20 in parts and good project for entry level hackers
-battery box can be super tiny. baby-bic size if built on 2 3V cr2032 coin cells or a single 6V 4SR44 or 4LR44
-is "official schoeps part" for the snobbish
disadvantage of CMR relative to N-bobs:
-higher cost
-slightly larger (longer) on the active end
-3-4 dB penalty in sensitivity vs 60V polarized caps (nearly moot point for most live taping situations)
-high voltage capsule polarization circuit is probably above the skill level of most DIYers, so youre dropping $200-$500 on a solution to power them (prob a wash on cost of n-bobs vs cmrs in most cases, but something to be aware of)
ive been a schoeps guy for decades. CMRs since 07. However,i cant deny the versatility of the DPAs in form and function so will be trying that for awhile. The fact that the smaller 4061/4099 series is compatible with the same solution that would run full size caps is great. There is not a show i couldnt get 4061s into. with the right caps in right location, there is almost nothing schoeps can do that DPA cant. would be nice if they had vertical diaphragm caps like 4V and 41V that had that ultra smooth off-axis response but hey what can you do? both of those caps come with a significant size penalty as well. DPAs omnis and subcards are right there with the best in the world