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Mike Rivers[_2_] Mike Rivers[_2_] is offline
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Default dynamic omni vs condenser for low noise.

On 12/30/2019 4:58 PM, Tobiah wrote:
It would seem that a dynamic mic has no self-noise, is that so?


For small values of "no," yes. No microphone has no self-noise. A
dynamic mic doesn't have amplifier noise (tubes, semiconductors that
make hiss, hum, and buzz if not implemented well) but it has wire and
resistance, that that has noise.

Yet to get the same gain as a condenser one has to crank the gain
up much more on the dynamic, raising the noise level.


Microphones don't have gain, they have sensitivity, and, yes, the
sensitivity of a dynamic mic is typically lower than that of a condenser
mic. Therefore, to get the same recording level from a given source,
you'd need more preamp gain with a dynamic than a condenser, and the
noise that you're adding with that additional gain is electronic noise.
There's no free lunch, except almost, with a transformer, which is why
most dynamic mics have a transformer inside.

Is it ever
the case that when recording soft sounds, one could get a lower
noise recording with a dynamic?Â* Would it take a very expensive
preamp to achieve this?


I assume you're asking if you can get lower noise with a dynamic mic,
assuming you have a really quiet, high gain preamp, than you can with an
unknown condenser mic and preamp with unknown noise characteristics?
That's a "maybe." You're juggling a lot of variables here, and I think
you're only looking at electrical noise. The really quiet condenser mic
to which you're comparing a dynamic mic might be omnidirectional and
will pick up your neighbor's leaf blower better than the really high
output cardioid mic.

I would guess that the output level of the dynamic would be
key.Â* Any recommendations for a high-output omni dynamic for
$100-200?


Yeah. The quietest condenser mic you can find in that price range. But
it might not be the best mic for your source.

You would get better answers if your this-or-that questions weren't so
abstract. Do you want to record crickets in your back yard at night? Do
you want to record a softly picked guitar or mountain dulcimer at a
distance of a foot or two from the mic? Do you want to record a bagpipe
band from as far away as you can get from them? You'd want a different
mic for each situation, and you might have to eliminate your best choice
if you get too much noise. Or you might just have to move the mic closer
to the source.


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