>
>Until then I repeat: If you hear noise, you can never lower this noise by
>using a preamp.
Should of course be: If you hear MICROPHONE noise, you can never lower this
noise by
using a preamp.
>Klas.
>
>
>
>
> >Rob D: wrote and realized soon afterwards,..
> >
> > >
> > >
> > >At 12:22 PM +0200 4/21/05, Klas Strandberg wrote:
> > >> >Since the 957 already terminated in an 1/8th mini jack, and uses
> > >>>plug-in power? Or maybe it's battery operated? I'm not sure how much
> > >>>you'd gain by adding a preamp. I think we're mainly referring to
> > >>>phantom powered mics using external preamps. That being said, I know
> > >>>often the minidisc mic input isn't the cleanest, and if you can go in
> > >>>line level, you'll bypass some of the noise.
> > >>
> > >>
> > >>I clam that that statement is common but wrong.
> > >>Give me some proof!
> > >>
> > >>Klas.
> > >>
> > >
> > >m("sbcglobal.net/vwp2?.tok","//f2.pg.briefcase.yahoo.com/bc/rob_danielson");">http:
> > =bcmKTRVBNxZgHObW&.dir=/Tests&.dnm=CompareMiniDiscMicPreNoise.mov&.src=bc
> > >
> > >Right-click on the paper-looking document and select, "Download
> > >linked files as,.." option.
> > >
> > >I've uploaded the above 2.3 mb QuickTime movie that compares the
> > >resultant noise from Rode Nt3 and Nt4 mics using a HiMD mic input
> > >jack and the same mics routed through a Sound Devces MP-2 outboard
> > >preamplifier into the HiMD's line input. The recordings were made at
> > >16/44.1; the QuickTime movie has an IMA:4 compressed sound track so
> > >that more people can download it. Again, these tests are for quiet
> > >location recording situations where high gain is more likely to be
> > >used. The files are well saturated and loud, be sure to adjust
> > >playback volume to a comfortable level
> > >
> > >To my ears, the NT3 presents a fairly close match between internal
> > >and external preamp noise which suggests to me that an "effective
> > >self-noise" rating for the NH-900 HiMD recorder's mic pre _with this
> > >particular mic_ is in the ballpark of 16 dBA. [The self noise
> > >equivalent for the MP-2 (with some conservative assumption involved)
> > >is in the area of 5dBA, so its very unlikely to be adding noise.]
> > >
> > >I say only for "this particular mic" because, as we found before,
> > >sensitivity (output) and other factors come into play. You will note
> > >that I had to boost the playback level of the NT4's recording 14dB to
> > >match the playback level of the NT3's recording. Even though both
> > >mics have very close self noise specs (16dBA for the NT4 and 17dBA
> > >for the NT3), the noise component in the NT-4's recording is also
> > >increased 14dB to match playback leve with the NT3's. The addition
> > >of noise from the HiMD mic pre can be confirmed by looking at the NT4
> > >signal routed through the MP2 where we hear less noise than that from
> > >the recording where the NT4 is connected to the HiMD recorder's mic
> > >pre.
> > >
> > >The NT3's recording (apparently taking advantage of effective higher
> > >output) exhibits about the same noise as the recording made when the
> > >NT3 routed through the MP2. This suggests to me that a HiMD mic
> > >preamp is more likely to introduce significant noise when the record
> > >level is high and the mic does not have high output. This is
> > >consistent with our theory of why the Shure 183 performed well with
> > >22.5dBA noise in the prior test with its high sensitivity of 42 mv/Pa.
> > >
> > >So, there is no simple way to put MD mic preamp noise into a general
> > >"effective self noise" number because performance is the result of
> > >speciifc mic-preamp combinations. If you need further proof of this
> > >phenomenon, according to Rode, the NT3 and the NT4 have equal
> > >sensitivity (12 mv/Pa). Their output impedance is also matched at
> > >200 ohms.
> > >
> > >I tested the mics from the first test again and I feel the results of
> > >the first test are very reliable. That's is available as a small
> > >.mov now:
> > >
> > >http://www.micbooster.com/movies/TransMic&PreTestSor3_IMA.mov
> > >
> > >People commented on the appreciable leap in quality that happened
> > >with the NT1A/Mp2 in the first test so I'm testing some higher end
> > >mic-pre combos. Rob D.
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >"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
>
>
>
>
Telinga Microphones, Botarbo,
S-748 96 Tobo, Sweden.
Phone & fax int + 295 310 01
email:
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