John Curl's Blowtorch preamplifier part III

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Ewrong again. Most modern codensers are fet amped not transformers. Did you really look inside any. And let AKG and Nuemann know about your goop, you'll be rich. Not likely.
I mean and well understand phantom powered FET amplifier (true condensor or electret transducer derived signal) driving output line driver/balancing transformer.
Passive dynamic transducer (eg SM57/58 etc) driving output balancing transformer is a different case.
Mr AKG might be surprised how much a C414 can be improved.

Dan.
 
One of the major differences is phase.

Dynamic mikes deliver max output at zero crossings, condensors at max excursion. Therefore, you cannot mix the two types when miking an instrument (book knowledge, don't know how it pans out in real life).
Really? Both types (if omnis) convert sound pressure and both are minimum-phase systems, so if the have the same SPL magnitude response they also must have identical phase response.
Do you have a reference?
 
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RF condenser mikes have one other benefit- no electrostatic stress on the diaphragm. The can be push-pull as well so some distortion reduction possible and the diaphragm does not need to be tensioned as high to withstand the electrostatic forces. Extended LF response is also possible. Now to find that old Sennheiser MKH104. . . oops, gave it to Keith Johnson who uses it as part of his main recording array.
 
RF condenser mikes are yet another challenge. They operate on such a different principle, that it might be difficult to estimate their distortion, due to the different way the signal is processed. They can sound good, but they WILL CLIP if not adjusted for sensitivity. The Grateful Dead used these RF mikes before we changed to differential B&K 4133 capsules for the Wall of Sound. The RF mikes were modified to have lower sensitivity. They were certainly better sounding than typical dynamic mikes at the time.
 
RF condenser mikes have one other benefit- no electrostatic stress on the diaphragm. The can be push-pull as well so some distortion reduction possible and the diaphragm does not need to be tensioned as high to withstand the electrostatic forces. Extended LF response is also possible. Now to find that old Sennheiser MKH104. . . oops, gave it to Keith Johnson who uses it as part of his main recording array.
LF response can actually extend to DC (sans the capsule itself which should have a tiny duct to allow for overall atmospheric pressure changes). That's why I've been thinking about using the concept for a precision excursion sensor for woofer MFB...
http://www.sdiy.org/oid/mics/Senheiser-MKHs-SM.pdf
 
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They are both condensor mics the electret has a permanent charge trapped in a very high bulk resistivity film (like TFE). It acts like the polarizing voltage is always there. There is no difference at all in the basic operating principle.

The RF mics are a basically a parametric amplifier with the capacitance forming a tuned circuit with the change in capacitance changing the center frequency. The noise ends up being related to the Q of the tuned circuit. There is no high impedance circuitry so they are very moisture resistant and no bias resistor noise so they approach the brownian noise limit.

Think about another thing, most condensor mics are like electrostatic speakers with one stator, hence the dominant seconds in distortion.
 
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They are both condensor mics the electret has a permanent charge trapped in a very high bulk resistivity film (like TFE). It acts like the polarizing voltage is always there. There is no difference at all in the basic operating principle.
I'm not an expert in microphones manufacture, but, if I'm not wrong, the difference is that, because this special film, it is difficult to equal the physical qualities of a simple film coated with gold. Am-I wrong ?
Too, if industry made a lot of progress in that matter, last decades, what about the durability of the électret charge on the long time ?

If it was so simple, I suppose the makers would have all abandoned the traditional electrostatic capsules ?

PS: The best studios electrostatic mics are symmetrical, with two plates (stators), indeed.
 
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He just likes to insult people who are less technical than him.

You are the one to say so :D. Your disparaging comments like "many here do not have a clue ....." are famous.

I honestly did not see the post as a bad mood post.

I believe it was a comment on how the various descriptors used can come across as unusual, funny. We are all guilty of using descriptors that others may consider different..

john

"Funny" I meant that the clean one was called dirtier. This is very usual that distorted is considered cleaner. I would not expect it on a sine tone. But in this case, I assume no one would tell the difference in ABX.

The problem with audio is that we often make a choice of something that is pleasing our imperfect or flawed hearing, even if it distorts the sound. Of course, impossible to admit ;)
 
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