Thanks Klas. This is one of the most compelling responses I've read in all =
the archives. Correct me if I'm wrong, but you're saying a few dB of differ=
ence is really not a big deal, only noticeable with a special low output vo=
ltage external mic. And that such a low voltage external microphone is not =
even available to buy. Doesn't this largely contradict any quibbling argume=
nts over noise floor?
Are there any mics you can recommend to pick up frog sounds and ambiance in=
a quiet outdoor environment? The LS-100 is now available, and it has XLR i=
ns, perhaps that's the best choice for external mic flexibility.
Thanks,
Rich
--- In Klas Strandberg <> wrot=
e:
>
> Thanks Bill, always accurate!
>
> You write:
>
> >This means the LS-11 preamp is 3dBu quieter than the LS-7 under
> >these test conditions. That's a difference that you will be able to
> >hear in your recordings, but
>
> 1: only if you use an external mic that has very low self noise, and
> 2: when recording in a space that has a very quiet ambience.
>
> and, I would add, most important:
>
> 3: if the external microphone has such a low output voltage / Pa that
> it=C2=B4s signal needs to be amplified a lot by the recorder mic input am=
plifier.
>
> On the other hand, which is what I suggest, is that there are no such
> low output mikes on the market today. Even a small one dollar
> electret will have an output which is high enough to run over the
> noise of a 110-115 dBu recorder noise.
>
> Some history to spread light on the mic preamp noise as a "holy cow",
> when 1 or 2 db mattered.
>
> In 1975, a typical recording birder in Sweden would buy a Beyer ME80
> to put in his parabol. He chose it because it had a flat freq.
> response, which he was told was "the best". Probably he would have
> preferred to buy a MKH, but he could not afford it. Instead he spent
> the rest of his money on a used Nagra III.
> But the output voltage of ME80 was only 1,5 mV/Pa, which meant that
> the Nagra would have to amplify the signal about 1000 times (60dB) to
> feed the Nagra recording head enough to saturate the tape. Not even
> the Nagra III input was good enough to amplify 60 dB without adding
> "hiss". So, if you wanted "hiss.free" recordings, you had to use a
> big parabol and the bird had to be really close.
>
> Sten Wahlstr=C3=B6m, at the time, found that Sennheiser MD21 gave almost =
3
> mV/ Pa and that there was a company in Stockholm making a special
> transformer for it. Using this transformer with the most low noise
> transistor of the time, 1N930, he succeeded in making a preamp that
> performed much better than even the Nagra III.
>
> Those were the times when preamp noise was very important! It was
> "all" as a matter of facts and the biggest challenge for
> naturerecordists struggling with noise / hiss!
> But today is different. Even in the 90-th, you could buy a cheap
> electret which performed almost as good - and better - than the best
> condensor microphones 10 years earlier! Primo made a 10 mm capsule
> called EM60, which - connected to a Nagra III input - provided such a
> high output that what you heard was the mic noise, not the Nagra noise.
>
> To all people asking what recorder to use - go on the price, weight,
> menus, battery life - buy a recorder that you like to use - don't
> sacrifice any such "qualities" for some 3 dBu less input noise.
>
> Klas.
>
>
> At 06:35 2011-06-04, you wrote:
> >Peter,
> >
> >The Avisoft web pages include a tutorial that helps explain what the
> >recorder preamp noise specifications mean.
> >http://www.avisoft.com/tutorial_mic_recorder.htm
> >
> >Consider these specifications only:
> >Olympus LS-11 -122dBu unweighted
> >Olympus LS-7 -118dBu unweighted
> >
> >This means the LS-11 preamp is 3dBu quieter than the LS-7 under
> >these test conditions. That's a difference that you will be able to
> >hear in your recordings, but only if you use an external mic that
> >has very low self noise, and when recording in a space that has a
> >very quiet ambience. If you're recording louder sounds, or using a
> >mic with more self noise, the recorder self noise will be masked
> >under most circumstances.
> >
> >Results from pocket recorders almost always can be improved by the
> >use of a good quality external microphone. For example, Klas
> >Strandberg has introduced a model designed for the Olympus LS-xx
> >models. http://www.telinga.com/ls10.htm Unfortunately, you'll need
> >to spend quite a bit more than the cost of the recorder on such a microp=
hone.
> >
> >For the record, neither the LS-11 nor the LS-7 is considered a good
> >solution by itself as a primary field recorder. These are
> >pocket-size models that best serve as casual recorders note-taking
> >machines. They can be pressed into service as a primary recorder
> >when you want to travel light, or need a less obtrusive recording kit.
> >
> >If you're looking to make very high quality recordings, none of the
> >pocket recorders is a good solution. In the less-than-$1000 range,
> >take a look at the Fostex FR-2LE recorder. And expect to pay an
> >additional $1000 to $2000 for microphones, cables, wind screens and
> >mic stands. Professional gear costs a lot, but delivers superior
> >results, increased durability, and improved ease of use under
> >difficult conditions.
> >
> >Does this mean you can't make an excellent recording with an
> >inexpensive pocket recorder? No, but the conditions have to be just rig=
ht.
> >
> >Many vendors of recording equipment will allow you to try out a
> >recorder for a few days to see if meets your requirements. Try
> >several models to see which one works best for you.
> >
> >--oryoki
> >
> >
> >
> >
> >------------------------------------
> >
> >"While a picture is worth a thousand words, a
> >sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause=
.
> >
> >Yahoo! Groups Links
> >
> >
> >
> Telinga Microphones, Botarbo,
> S-748 96 Tobo, Sweden.
> Phone & fax int + 295 310 01
> email:
> website: www.telinga.com
>
>
>
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