[Nate Najar]

I got it about 6 months ago on a trade. I didn't really need another mic but I had a rack mount guitar power amp that was a mildly esoteric item and a guy wanted it and offered this for trade. At the very least I thought I could sell the mic easier than the amp.

I am completely addicted to how quiet this microphone is. It's really almost kind of spooky. I do a lot of little cues and clips here and there so I spend a good amount of time with the headphones on.

As an added bonus it's a terrific sounding mic. I've only used it on my guitar, but I'm really happy with the way it sounds. I still have to keep it at least 24" away in order to get a uniform freq response and also capture the sound of the entire guitar. With this guitar I have to put the schoeps (I have the mk41) about 36" back for the same uniformity.

I'm thinking I want to try the omni. It would be nice to mic the instrument closer for ensemble work instead of having to use isolation. They seem to be going used for not that much more than a schoeps capsule, and the bonus is that I get a whole new mic.

My holy grail is still the schoeps mk21. I demoed a pair a few years ago and I remember them very fondly. little to no proximity effect and some amount of directionality. I don't know how they did it. But I haven't bought one because, where I would want that as a spot I would also need a stereo pair for the ensemble and that's what I use the schoeps for. So I can't just buy a capsule, I would need a new body too, and that's a fairly large expense.

But man this mkh is unbelievably quiet. Room tone isn't bad at all in this particular room, so it's just silence in the cans unless you make music. It's really quite remarkable.

[Phil Allison[_4_]]

Nate Najar wrote:

Sennheiser MKH40 cardioid condenser mic.


I am completely addicted to how quiet this microphone is.
It's really almost kind of spooky. I do a lot of little
cues and clips here and there so I spend a good amount of
time with the headphones on.
As an added bonus it's a terrific sounding mic.


** Sennheiser's MKH series use diaphragm movement and resulting capacitance changes to directly modulate a radio frequency of about 8 to 10MHz. Early models used FM while later ones like the MKH40 use AM to produce an audio signal.

This is quite unlike other condenser mics which rely on charging the capsule to a high DC voltage from gigohm impedance sources to make it generate audio signals directly into a FET or tube preamp.

Using radio frequencies in this way means only low impedances are involved, which produces considerably less audio frequency noise than the DC charge method. It also means the capsule is not sensitive to moisture or humidity in the way most other condenser mics are.

This white paper from Sennheiser supplies many details to the story, without adding too much BS.

http://en-de.sennheiser.com/download...tePaper_en.pdf

BTW: despite the very low noise levels of MKH series mics, no claim is made that you can hear Brownian motion of air molecules using one.


..... Phil

[Scott Dorsey]

Phil Allison wrote:

BTW: despite the very low noise levels of MKH series mics, no claim is made=
that you can hear Brownian motion of air molecules using one.

It's quite the opposite! With most modern condenser microphones, Brownian
motion of air is the dominant noise source at high frequencies, with the
noise from the front end being mostly 1/f rumble.

You can demonstrate this by removing the capsule from a mike that has an
external FET and replacing the capsule with a shunt capacitor of similar
value, in a sealed silent box. The difference in noise is all Brownian
movement (and experimental error from leaked noise).

The thing about the MKH-series microphones is they employ a tensioning
and equalization trick which results in reduction in Brownian noise,
so the actual noise floor of the capsule itself is lower than the theoretical
noise floor for a similarly-sized conventional capsule. Add that to the
FM arrangement and you get a really, really silent mike.

The tensioning trick is no great secret; Neumann's TLM103 uses it also.
But it has some audible side effects. That's life.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."