Hi Klug,
Very interesting posting.
You have successfully triggered my curiosity: How can a bunch of empty tubes could be so good in capturing dim sounds??.
I downloaded a translated version of the page in Russian (thanks Babel Fish). I also have found an article written in English that, perhaps; is the original one. It was originally published in 1965.
**broken link removed**
**broken link removed**
With the Russian article, plus these two articles ones, and some more about sound waves, I‘ve been working hard trying to understand the physics behind the project. Still I have a part of the puzzle to be solved: You said that for voice, only 8 tubes are necessary. However according my calculations (might be wrong) with tubes of 10mm of diameter, temperature of 15ºC, a correction of 0.8D for diameter and with an acoustic Q=15, the only way that I have found is accepting that the system will work over the fundamental frequency and the first 6 overtones (n= 1, 2, 3, 4, 5, 6, 7). Is that right?
Do you know the right way to calculate the bandwidth of the acoustic system?
Best regards
Gil