Hi Klas--
I agree that people need to understand that the self noise component is fix=
ed.
I'm trying to address the questions we get about which entry level
mics will produce less noise when recording ambient space with an MD
recorder. I haven't come across anything specifying equivalent self
noise for MD mic preamps. Maybe a reader who has both an MS-957 and
Shure 183's could do a test to give us better sense of the noise
affects of the MD mic pre (and affects of greater sensitivity) for
the FAQ. Seems to that many ask about PIP MD mic options that produce
less noise and why. A follow-up FAQ question might be, "If I spend
more on expensive mics, what will the improvement sound like?" Its
more than any of us has the gear and time to do alone but maybe as a
group we can post some very informative test files.
On a related matter, I just finished a mix for a video soundtrack
with Rob Yeo who recorded many hours of material with EM-23's and his
Sharp MD (pip). I was very impressed with the transparency of these
mics and how little noise there was-- especially in the upper
frequencies. I almost never touched the eq above 1200Hz even to
soften the edge on blowing grass etc. Very nice. Are you still
selling these mics? Rob D.
=3D =3D =3D =3D =3D
At 10:35 PM +0100 2/15/05, Klas Strandberg wrote:
>Mic noise is one thing - mic preamp noise is something else.
>
>If the output / Pa of a microphone is low, - then you have to use a lot of
>preamp gain to get the signal up, but then you will hear the preamp noise!=
!
>- not the mic noise!
>
>If a mic has a 23 db self noise, its still has a 23 db self noise, even if
>the output is high.
>
>In practice you could be correct: A low output microphone with a good self
>noise might give a poorer result than a high output mic with a poorer self
>noise. But then it is because of preamp noise, and could be improved by
>getting a better preamp.
>
>The word "sensitivity" is also used by the Japs to describe self noise,
>instead of dbA.
>It's very confusing.
>
>Klas
>
>
>At 16:24 2005-02-15, you wrote:
>
>>Citations about actual places, their sound levels, instrument specs
>>and associated sound files like Klas's would be a great addition to
>>an FAQ page wouldn't they?
>>
>>Another key factor that might also be added to the discussion about
>>self noise is "sensitivity." The MKH's have both low noise and high
>>sensitivity. The KM-23, though it has a very respectable rating of
>>16dB(A) self noise, also has high sensitivity. The Sony MS-957 has a
>>considerably higher value of noise @ 25 dB(A) but the presence of
>>this noise in the signal is more apparent because its sensitivity is
>>only ~6 mV/Pa and the record gain in quiet locations must be
>>increased for sufficient record volume. The Shure WL-183 has
>>22.5dB(A) self noise but its high sensitivity of 40 mV/Pa allows it
>>to take greater advantage of its moderate self noise. The ideal
>>combination of low self noise and high sensitivity contribute to a
>>mic's ability to perform well under "very quiet" conditions. So,
>>high "mV/Pa" numbers are good and low "dB(A)" numbers are good. Any
> >number above 20mVPa is very good; any number below 10dB(A) is very
>>good. Mic manufacturers' testing methods vary considerably, so the
>>published numbers should only be regarded as ballpark "estimates"
>>until proven in the field. Many terrific recordings have been made
>>with modest gear that is perfectly suited for the situation--
>>including sound levels. The placement of the mics in the sound field
> >can make the recording sing or seem dull. Rob D.
>>
>> =3D =3D =3D =3D
>>
>>At 11:32 AM +0100 2/15/05, Klas Strandberg wrote:
>> >A general statement which is almost true:
>> >
>> >Considering "sound quality", all microphones today are as good as the =
best
>> >ones 20 years ago.
>> >So don't worry about sound quality, frequency response etc. It's good
>> enough.
>> >
>> >Then the noise problem:
>> >
>> >Listen to "My Garden" on telinga.com, click sound gallery.
>> >The microphones in question had an inherent noise level of some 8-9 db=
A.
> > >That's low.
>> >
>> >In this category of mic's you will find the Sennheiser MKH series, the
>> >telinga MPS1 series and all those recently marketed low-noise mic's us=
ing
>> >the same China-made 1 inch capsule, like the CAD 179 for example. (Tho=
se
>> >China capsules are very different from one another! You need to match =
them
>> >to get a stereo pair!)
>> >
>> >If you replay such a recording at a reasonably low level, like in real=
ity
>> >or a bit louder, 10 dbA will not be audible at a recording like
>>"my garden".
>> >16 dbA will be audible, but not disturbing.
>> >23 dbA will be disturbing and something which you will try to filter a=
way.
>> >Roughly.
>> >
>> >Considering an owl, 50 meters away, deadly silent around - 16 dbA will=
not
>> >only be audible, but also disturbing.
>> >
>> >Noise is related to size. The bigger the membrane is, the easier it is=
to
>> >make it low noise.
>> >All 5 mm electrets have a noise level about 30 dbA or worse. All 10 mm
>> >capsules have a noise level at about 26 dbA or worse. (All except one)
>> >All 20 mm capsules, like Sennheiser ME-series and Telinga EM23, make a=
bout
>> >16 dbA noise, or worse.
>> >The Sennheiser MKH and Telinga MPS1 are here exceptional. They have 20=
mm
>> >membranes, but a noise which is only 10 dbA or better.
>> >
>> >Hope it helps a bit.
>> >
>> >Klas.
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> >.
>> >
>> >
>> >At 04:33 2005-02-13, you wrote:
>> >
>> >>Im one those who Walter refers in a previous thread
>> >>
>> >>"It could be very easy for this group to become nothing but technical
>> >>discussions. But that would not be very attractive to new folks to
>> >>nature recording. We need to get them hooked before we drop the ton o=
f
>> >>technological bricks on them. You can record well without understandi=
ng
>> >>the terminology, though it's easier if you do understand the
>> >>implications of that stuff."
>> >>
>> >>Even after followering to the group for several months now I still
>> >>having a lot of trouble appreciating what is a good mic and how that
>> >>relates to the dollar sign. From recent messages I'm not the only one=
.
>> >>Some of this is terminology and unfortunitly I can not access the lin=
k
>> >>on the groups home page which may help. Then there are varous
>> > >specifacations one reads for example self noise, is very important =
but
>> >>the difference between a mic with 25dB and 40dB are still figures.
>> >>Something that I could relate to is how much closer am I going to get=
to
>> >>that bird for the same recording. The some for self noise (how much
>> >>extra hiss I'm going to hear in the background with an extra 10dB ) a=
nd
>> >>there is sound to noise ratio. Other specifications such as output
>> >>Impedance and Dynamic Range are just figures.
>> >>
>> >>I have looked at a number of sites that has a general advise on tools
>> >>and methods. Also there have been a number of references on what mak=
es
>> >>a good mic in this group but there is hell a lot of messages to read =
to
>> >>get a grasp of it all. I'm asking the impossible, can there be a set =
of
>> >>guidelines amongst the group that would make an ideal mic, one that
>> >>would do the job and those that will disappoint you for individual ca=
lls
>> >>vs ambiance recordings. There is no need to mention specific makes of
>> >>mics or other additions such as barriers as one needs to get a grasp =
of
>> >>the basics befor being side tracked down another path. Some one could
>> >>explain in practical terms what the varies specifications are. This
>> >>maybe a useful reference for the home page.
>> >>David
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>--
>> >>No virus found in this outgoing message.
>> >>Checked by AVG Anti-Virus.
>> >>Version: 7.0.300 / Virus Database: 265.8.7 - Release Date: 10/02/05
>> >>
>> >>
>> >>
>> >>
>> >>"Microphones are not ears,
>> >>Loudspeakers are not birds,
>> >>A listening room is not nature."
>> >>Klas Strandberg
>> >>Yahoo! Groups Links
>> >>
>> >>
>> >>
>> >>
>> >
>> >Telinga Microphones, Botarbo,
>> >S-748 96 Tobo, Sweden.
>> >Phone & fax int + 295 310 01
>> >email:
>> >
>> >
>> >
>> >
>> >
>> >"Microphones are not ears,
>> >Loudspeakers are not birds,
> > >A listening room is not nature."
>> >Klas Strandberg
>> >Yahoo! Groups Links
>> >
>> >
>> >
>> >
>>
>>
>>--
>>Rob Danielson
>>Film Department
>>University of Wisconsin-Milwaukee
>>
>>
>>
>>"Microphones are not ears,
>>Loudspeakers are not birds,
>>A listening room is not nature."
>>Klas Strandberg
>>Yahoo! Groups Links
>>
>>
>>
>>
>
>Telinga Microphones, Botarbo,
>S-748 96 Tobo, Sweden.
>Phone & fax int + 295 310 01
>email:
>
>
>
>
>
>"Microphones are not ears,
>Loudspeakers are not birds,
>A listening room is not nature."
>Klas Strandberg
>Yahoo! Groups Links
>
>
>
>
--
Rob Danielson
Film Department
University of Wisconsin-Milwaukee
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