Thanks Rob, yes, I would like to swing a barrel of malt with you even
though I have not downloaded your files. I don't have quick time, for examp=
le.
I'll be back here tomorrow or Monday.
I will present some results, too. For the first time ever (??) I can
display true frequency outdoor measurements of a parabol (telinga) made at=
25 meters under realistic conditions. Curves and pictures.
It's not much new to discover on these results, but a healthy check up of
present theory and findings.
I hope to get the curve pictures tomorrow.
Klas.
At 08:54 2005-07-16, you wrote:
>"The cheapest little chip amp has a better noise
>performance than the best mic amps 10-15 years
>ago. You can presume [the mic input] is good,
>(low noise) enough."
>
> -Klas Strandberg 3/25/05
>
>5 years ago, on the advice of several pro
>recordists, I bought a $700 external mic preamp
>and a $1200 pair of condenser mics and soon
>joined the chorus citing the consumer MD/DAT mic
>pre circuit as the weakest link in coaxing low
>noise performance-- especially using high gain in
>quiet places. I didn't have any better
>explanation why the noise dropped so dramatically
>in my recordings . A couple of years ago, the
>$200 Rode NT1-A mic appeared with ~6dBA self
>noise and ~25mv/Pa sensitivity. I bought a pair
>and became interested in whether one could
>assemble a much lower cost, low noise
>mic-pre-recorder system out of the many options
>out there. I tried several lower cost external
>mic pres, mods and started running hi gain record
>tests to pin down the inconsistences I was
>getting with mics connected to the HiMD mic
>input. Klas Srandberg took a look at these tests
>and kept insisting that the mic input circuit was
>not responsible for the noise. How to test this?
>Dan Dugan sent me some nice Denecke PS-2 phantom
>power supplies to try but they created a fizz
>that I could not eliminate. I ordered parts to
>build a portable unit using 5 X 9volt batteries
>based on a schematic drawn up by Klas, when I ran
>into Paul Dickinson who told me that Ross Corp
>had just come out with a beefier, battery powered
>phantom supply for only $70 that I might want to
>try.
>
>http://www.music123.com/Rolls-PB224-Dual--Phantom-Power--Adaptor-i11829.mu=
sic?source=3Dfroogle
>
>Well, it looks like there could finally be a way
>to hear/assess the noise floor of the HiMD mic
>pre.
>
>In the test movie, there are four tests, back to
>back that are so close in performance that you
>might think there's only one sound sample! Listen
>carefully, the audio changes occur at the same
>time as the change in the picture. The gear
>set-ups compared in the first four tests are:
>
>1) NT1A-s Mics->722 Sound Devices Recorder
>2) Same Mics-> using Rolls PB244 Phantom power
>supply-> 722 Sound Devices Recorder.
>3) Same Mics-> Sound Devices MixPre -> Line input Sony HiMD NH900 recorder
>4) Same Mics-> using Rolls PB244 Phantom power
>supply-> 3.5mm Mic Input Sony HiMD NH900 recorder
>
>The next two tests include familiar
>PIP-compatible friends-- the Shure 183's and Rode
>NT-4's for comparison.
>
>Finally, I couldn't resist juxtaposing the $2800
>(1) package with the $700 (4) package.
>
>
>4mb version with compressed sound
>http://www.uwm.edu/~type/Mic%20Preamps/RollsPB224-%3eHiMDMicPreIMA.mov
>
>8.4 mb version - uncompressed sound:
>http://www.uwm.edu/~type/Mic%20Preamps/RollsPB224-%3eHiMDMicPreAIF.mov
>
>The QuickTime movie should stream in your browser
>if you have a fast connection or you can download
>the movie(s) by going to the directory at:
>
>http://www.uwm.edu/~type/Mic%20Preamps/
>
>and look alphabetically for the links
>
>RollsPB224-_3eHiMDMicPreIMA.mov
>or
>RollsPB224-3eHiMDMicPreAIF.mov
>
>to right-click( mac option-click) on.
>
>Think I'll go pour a single malt whiskey now.
>Seems more affordable. May I be the first to
>toast Klas?! Rob D.
>
> =3D =3D =3D
>
>At 12:58 PM +0100 3/25/05, Klas Strandberg wrote:
> >No, not too early, cause nowadays there is no reason to make a mic input
> >noisy. You can presume it is good (low noise) enough.
> >
> >The cheapest little chip amp has a better noise performance than the bes=
t
> >mic amps 10-15 years ago.
> >
> >The design challenge is to make a mic preamp running on 1/ low voltage, =
2/
> >low current consumption, still 3/ good headroom and 4/ low noise.
> >
> >All "walkman" size recorders that I know of sacrifices the headroom in
> >favour of low noise.
> >
> >Klas.
> >
> >
> >
> >At 03:42 2005-03-25, you wrote:
> >
> >>Might be too early to conclude the R-4's mic pre quality is good
> >>enough for the general sensitivity of "todays" mics. Of course,
> >>Volker's thunderstorm is not a good recording situation for judging
> > >noise. Side-by-side comparison tests with known gear can be very,
> >>very telling. It could also be the R-4, like the R-1, is designed
> >>more for music recording with a mic pre gain of 40dB compared to the
> >>~55-60dB we're used to with MD's. That would be consistent with the
> >>Oades' report. Rob D.
> >>
> >> =3D =3D =3D =3D =3D
> >>
> >>At 2:21 AM +0100 3/25/05, Klas Strandberg wrote:
> >> >At 00:45 2005-03-25, you wrote:
> >> >
> >> >>It would be great if they could specify what they mean by not so gr=
eat?
> >> >
> >> >I agree! Again: ALL mic inputs today are good enough if you use high=
> output
> >> >microphones!! Most microphones today are such high output mic's! Wha=
t is
> >> >the problem??
> >> >
> >> >Klas.
> >> >
> >> >
> >> >>I actually purchased an Edirol R4 recently.
> >> >>It was the Oade page that made me aware it existed.
> >> >>According to my dealer I am one of only few people to have one in
> Germany.
> >> >>
> >> >>My main interest in bying it is to make the switch away from DAT as=
> well
> >> >>as the 4 channel opportunity.
> >> >>
> >> >>My (couple of days) experience so far is quite positve.
> >> >>
> >> >>I've done 4 channel early spring birdsong recordings with a modifie=
d 4
> >> >>channel Jecklin disc (2 Audio Technica AT3031, 2 Audio Technica
> AT3032),
> >> >>that I like very much.
> >> >>With my mid class surround system, I feel in the middle of the fore=
st.
> >> >>
> >> >>Coming from Sony DAT and Sharp MD mic preamps, I am satisfied, but=
> I am by
> >> >>no means short of a recording professional.
> >> >>My main interest in recording is ambience anyway.
> >> >>Just today I did a recording of the first spring Thunderstorm from =
my
> >> >>balcony with a stereo Jecklin setup (AT3032 again).
> >> >>And I really rocks.
> >> >>
> >> >>In case there is anyone who would like to have more detail about th=
e
> >> >>Edirol R-4 or even sound samples, just let me know.
> >> >>I would also be interested in an exchange of experience with other=
> users.
> >> >>
> >> >>
> >> >>Volker
> >> >>
> >> >>
|