I think it will be very difficult to make polar patterns:
Suppose you move the sound source in a wide circe - diameter 50 meters or
more, how do you do that, practically, and how to prevent that the
loudspeaker works in different acoustics all the time?
Suppose you move the parabol around. It will "see" drastically different
acoustics, for each degree, in fact. Nevertheless, with common sense one
with draw better conclusions from such a test than without it.
Klas.
At 19:00 2004-02-28 -0500, you wrote:
>From: Klas Strandberg <>
>>
>> Walt, you know that I basically agree with you on this topic "theory /
>> experience". And I think there was a sometimes stupid discussion in the DAT
>> vs. MD debate. Let us not bring this parabol discussion to that point! But
>> here I think there is something else going on. I think there is a chance for
>> new discoveries! That's important!
>
>It would appear my opinions and speculations are not wanted. A year ago
>I was called dillusional because I maintained that the Telinga was, in
>my experience, providing gain and directionality even down at very low
>frequencies. This year I provide Sten's paper, which was one response to
>that. And, a year later and a lot more times recording with the Telinga
>and paying attention, I'm not one less bit dillusional. I've read Sten
>Wahlstrom's paper, and Swenson's, some time ago. I've evaluated both
>papers against the Telinga, which happens to be the parabolic I use.
>
>It might be well to read Swenson's paper as well, and since I'm sure few
>have bothered to go and get it from any of the dozens of places it's
>available on the internet, I've used some more of my web space for that:
>http://naturerecordist.home.mindspring.com/pat_mike.post.pdf
>It's particularily worthwhile reading his summary and conclusions.
>Though, I think he's a pessimist with very little experience in nature
>recording.
>
>I'm not near so hopeful for any new discoveries. Not unless people start
>thinking outside the small box they are in. And getting out and
>evaluating what they are saying while nature recording.
>
>> You know I can get really tired of people discussing parabols and theory,
>> mostly because it's just the same old prejudice and misunderstandings coming
>> back over and over again anyway, - but here and now we have some people who
>> want to find out things!
>
>I happen to have things I want to find out too.
>
>> Eric wants to experiment on how to measure a parabol, for example. Fine. I'm
>> greatful. Even if he won't find The Truth, he will perhaps find good and bad
>> ways to measure!?
>
>I'm really looking forward to those measurements, particularily the
>polar patterns. One of the good things likely to come out of this. I've
>been planning to set up a sort of system to do some polar patterns,
>particularily for the Crown WSA Dish, but also the Telinga. And later my
>own designs, this is clearly not the forum to discuss those. But it's
>been slow going finding the time to mess with that. I'm very thankful
>for Eric wanting to do it. It will probably be this fall at the soonest
>before I can do any of that.
>
>Frog season is here, I've three separate recording forays to do this
>coming week, to three entirely different parts of the state. If I don't
>wear down before the third. Plus I'm trying to get some mic testing of
>my own done.
>
>Walt
>
>
>
>
>
>"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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