Denis/malice
I have heard other people as well making a distinction in the sound of two mics that are , at least in theory, very closely related: The M269 and the U67.
First off, here are the only technical differences between a U67 and an M269 (non 'c' version) mic, contrary to what you might have heard regarding different frequency response components or circuitry:
-The tubes (EF86 vs. AC701)
-The voltage and current going to the tubes (beyond the scope of this forum.)
-The electronic components (resistors) which accomplish
that.(same as above.)
Over the years I have repeatedly made the following comparison test, in order to find out what factor that tube difference has on the sound of the mic:
I used two stock, well working units, both with Neumann selected Telefunken tubes, and both working at optimal operating conditions. I then transplanted one of the capsules back and forth, between M269 and U67 amp, so that the considerable influence of each capsule's individual sound was eliminated from the tests by using just one capsule for both mics.
What I found was an ever so slight softening of the dynamics with the M269. No large, fantastic revelations beyond that.
However, if you use the M269c's amp on that test, you will find the same, more noticeable characteristics shared with all cathode biased tube mics- a slendering of the mic's midrange, and a slightly increased transparency in the midrange, at the price of the robustness of the mids.
That's it.
All of these audible differences, by the way, are on a much smaller scale than the differences encountered when comparing two different K67 capsules. I suspect that Denis's wonderful mic's secret is the very capsule he has in that mic, over and above any other distinctions of model or series.
Kind regards,