It's nice to have quality text to read, isn't it....
One thing which J=F6rg (I have met him and discussed those things) didn't
mention is that a windfoam works better, the bigger it is; bigger - not
thicker.
The best windprotection is a big tent with no acoustics.
Klas.
At 00:52 2005-02-24, you wrote:
>Those who know me know that I tend to take an academic
>viewpoint on these things. I did a quick check of
>what has been published in the Journal of the Audio
>Engineering Society, and found a couple of helpful
>papers:
>
>"Microphones and Wind", Wuttke, Jorg; JAES, vol. 40,
>No. 10, 1992 October
>
>"Windnoise Meausrement using Real Wind"; Woolf, C,
>Prudden, O., AES preprint 5269, 109th Convention of
>the AES
>
>Jorg Wuttke is chief engineer of Schoeps. I'll try to
>give a brief synopsis of his paper here:
>
>Pressure microphones and pressure gradient microphones
>have different sensitivity to wind noise.
>Measurements presented at a wind speed of 18 kph for
>the Schoeps MK-2 (omni) and MK-41 (cardioid) show
>about 20 dB greater noise at low frequencies for the
>cardioid. The difference diminishes to about 10 dB at
>500 Hz. There is still significant wind noise at 1
>kHz.
>
>Both basket-type and foam windscreens can be
>effective. Foam windscreens tend to merely attenuate
>the highest frequencies (about 2 dB in the top octave
>for the one evaluated in this paper) whereas the
>basket type has less overall attenuation but
>introduces narrow-band peaks and dips amounting to
>about 10 dB peak-peak.
>
>The basket type windscreen is more effective at low
>frequencies, but less effective at mid and high
>frequencies than the foam windscreen.
>Quote "
>Conclusions
>
>Foam windscreens should be used wherever the
>protection they offer is sufficient, for their
>negative effect on the sound is relatively small and
>easily correctible. On pressure transducers they are
>almost always the best choice.
>
>Basket-style windscreens must be used on directional
>microphones if foam types are inadequate to reduce the
>levels of wind interference. They do detract from the
>sound and directivity of a pressure-gradient
>transducer to the degree that they are small and
>efficient. A good compromise between the two types is
>a hollow foam windscreen. In all cases care must be
>taken to avoid overloading the microphone channel's
>input electronics due to the excessive very low and
>even infrasonic frequencies produced by the action of
>wind on the microphone diaphragm. Attenuating the
>system's low-end response at the earliest opportunity
>is always a good idea to ensure a clean transmission.
>*******************************************
>end quote
>
>Now, if you don't happen to agree with this, don't
>shoot me. I'm only the messenger.
>
>eric
>
>
>
>"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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