There are way too many variables to pin down here without lots of time and =
a full lab to work in.
With regards to some previous emails on this subject:: replacing a mic caps=
ule with a capacitor may be very difficult to do quickly unless you have a =
de-mountable capsule such as the Oktavas. Even then, how do you get a good =
stable contact to the center pin and ground without making a special machin=
ed head to take the place of the capsule. And be sure to have all of this s=
tuff ready exactly when the "noise event" starts, then keep the environment=
al variables that provoked the event stable. Maybe the noise is caused by a=
bad ("cold") solder joint somewhere within the preamp that acts up under c=
ertain conditions. How do you test this? That effect can be very sporadic. =
BTW, I once had some noise events caused by a bad battery contact in the ph=
antom power supply.
My advice is for those of us who have had these problems is to put together=
a database of the model of mics, noise events, conditions, time, age of mi=
c, etc., to see if there is any type of correlation that can be gleaned for=
m this data. Perhaps a pattern will never be found. But at least we can per=
haps get some idea of what mics have what problem under what conditions. Mi=
cs that perform well and that don't make it to the "event list" would proba=
bly be good candidates for field work.
Peace & Happy New Year!