Do you think we'll be able to get a sensitivity number or even an
accurate range of mV/Pa : dbB(A) combinations that will apply to
DAT/MD/HiMD mic preamp's in general? I tested the Rode NT-1A's with
the Rolls phantom power supply with these recorders:
NH900 HiMD
Sharp MT-90
Sony D-7
Sony TRV-900 (video camcorder)
and found that the NH-900 is significantly quieter than the other
recorders with the Sharp MD being the noisiest.
I've been thinking about the min mV/Pa question since you posed it a
while ago. I came across table #3 on=20
http://www.rane.com/note148.html. With this chart, it seems like we
might be able to take what we know about the NH900 performance to
estimate the noise floor of NH900 mic pre for starters. I'm pretty
confident that the noises I'm hearing when I hook up:
NT1A->Rolls->NH-900 are close to a 50-50 blend of mic and NH900 mic
preamps. Applying the NT1A's specs* to table #3, I get ~-118 dBu for
the NH900 HiMD mic pre, but I'm blindly following the chart and other
aspects of the chart confuse me. Rob D.
*6dB(A); 25mV/Pa
=3D =3D =3D =3D =3D
At 11:34 AM +0200 9/1/05, Klas Strandberg wrote:
>With only 5,6 mV / Pa I am certain that you get MD preamp noise.
>You need too much gain.
>
>That is what I would like to discover: At which output / Pa does a typical
>MD preamp noise "take over".
>
>Klas.
>
>At 04:44 2005-09-01, you wrote:
>>At 5:07 PM -0700 8/31/05, Dan Dugan wrote:
>> >Lou Judson wrote:
>> >
>> >>Curiosity took me to the Soundprofessionlas website this morning, and=
I
>> >>see they have some closeouts on their stereo pairs already wired for
>> >>PIP - $49 instead of 129. Has anyone compared theirs to such as the
>> >>Shure 183s? Ths ones on sale now are cardioid, yet for some of what I
>> >>do they would be ideal.
>> >>
>> >>http://www.soundprofessionals.com/cgi-bin/gold/item/SP-CMC-22
>> >
>> >It was Sound Professionals who turned me on to the 183s, just before
>> >they changed to something else.
>> >
>> >Sharon Perry uses SP cardioids, which are Audio-Technicas, for her
>> >vest. Gain is about the same as 183s, but the cables are quite
>> >microphonic. Don't know if that's the type they're currently using.
>> >
>> >If the s/n of "58" is correct, 94-58 =3D 36dB, pretty high.
>>
>>and a (lower) sensitivity of 5.6mV/Pa (high mV/Pa #
>>[sensitivity.output] is good; low dB(A) # [self noise] is good.)
>>
>>compare to:
>>Panasonic WM61a capsule 32.5 dB(A)* 18 mV/Pa **
>>spec sheet: http://tinyurl.com/8g4l9
>>Cost $16.21 for 10 + shipppiing http://www.digikey.com/ and enter
>>"wm-61a" into parts search.
>>You can solder a workable set to run on MD/HiMD plug in power for a
>>few bucks more http://webpages.charter.net/tidmarsh/binmic/
>>
>>*Based on Eric B's test on file on the micbuilders list.
>>http://tinyurl.com/8tkt4 **Is this sensitivity number right? Eric's
>>test seems to confirm Panasonic's figure of (0dB=3D1V/Pa, 1kHz)
>>-35+/-4dB.
>>I need to learn how to make this conversion.
>>
>>and for reference:
>>ShureWL-183 22 dB(A) 29 mV/Pa
> >Rob D.
> >
>
>Telinga Microphones, Botarbo,
>S-748 96 Tobo, Sweden.
>Phone & fax int + 295 310 01
>email:
>
>
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