Folks, if you're not too anal about using the exact same mod that Scott Dorsey designed, you might just buy an MXL 1006. This is from a thread on rec.audio.pro:
>Did I read correctly in a post here from about a week ago that the new
>Marshall 1006 large diaphragm condender comes stock with electronics
>very similar to the mod that Scott published some months ago? Does
>anyone know how similar, or if it all? Is this mic a rebadge of the
>V57 that they only sold for a brief period of time?
If the 1006 is a rebadge of the V57, the overall circuit is very similar to
the one I used, which of course is a standard circuit that a lot of mike
manufacturers have used for decades. They don't use very good capacitors,
but I understand the need to keep costs down there. They do use a symmetric
drive stage and they do use a low noise input FET.
They also use a DC-DC converter to polarize the capsule at a higher voltage.
When I tried this, I found it emphasized unit-to-unit variations on the
capsules so I decided it was a bad idea in spite of improving the S/N.
The guys at Marshall are apparently selecting capsules at the higher voltage
and seem to have less trouble than you would if you added the same circuit
as an aftermarket mod.
--scott [Dorsey]