Sorry to say, you can forget a lot of what was called "professional
standards". They are not there even on todays "professional" gears, sometim=
es.
The question was why a base filter could not be applied in post
production and the answer was that the signal then already would be
clipped, perhaps.
That is an important thing to know.
I think many of the modern recorders work great for us naturesound
recordists, but one has to learn about every model, one by one, and
not go on any established standards.
I wish there were meaningful block-diagrams available on the
different consumer recorders.
Klas
At 19:03 2012-09-22, you wrote:
><<Scott, with modern recorders it has all got twisted and uncertain.
>1/ Using a certain recorder model "A" - where, in the chain, is the
>internal base filter? Will wind amplitude distort the input stage,
>even if the base filter is used? We don't know that, and it seems to
>vary with models.>>
>
>I was making the assumption, probably unwarranted, that the high
>pass filter is invoked prior to gain stages, as it is in
>professional gear. The proliferation of budget consumer devices has
>definitely muddied the waters when referring to professional
>recording procedures. The implementation of filters, pads, limiters,
>& even record gain setting in DSP (i.e. post AD conversion) renders
>the rationale for using these processes in the first place
>completely meaningless.
>
><<2/ How does recording level interact with noise? We don't know that
>either, and it varies with recorder models. The Olympus LS makes much
>more noise at 16bit than on 24bit, for example, regardless of the
>recording wheel setting. And noise figures vary a lot, depending on
>sensitivity setting "low" or "high", regardless of the recording
>level showing on the meter, but depending on the sample rate.
>Etc.>>
>
>I think by trying to make a device foolproof for amateur users
>manufacturers have made their products rather useless for people
>with enough experience to know how to set proper record levels.
>What's important to mention, regarding the question of high pass
>filtering when recording vs in post production, is that one cannot
>rely on high pass filtering alone to eliminate wind issues.
>Mechanical strategies, such as zeppelins, furries, fuzzies, foam
>socks, etc. are necessary to prevent wind from directly hitting the
>mic's diaphragm at full velocity. Once a physical membrane is in
>place, the high pass filter can, if needed (& if in a pre-gain place
>in the signal chain,) attenuate LF problems.
>
>Scott Fraser
>
>
>
>
>------------------------------------
>
>"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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