I have been told that egg cartons, and egg carton "foam" are not really good at absorbing much level wise - the range they do absorb is good, but the amount of decibels that they absorb is very small. Anyways when resolving standing wave issues, perhaps it would be good to look at "diffusion" which is essentially spreading the reflections of the direct wave in many directions rather than in just one or a few. I believe that that is where the egg cartons come into their own. And that is what Mr. Sabine's niches and statues do in Symphony Hall in Boston. If Ms. Wells were to take the 3 walls that are not the ones behind her when she practices and make their surfaces irregular, say with furniture, statues [busts of Rosetti might be good] or wall hangings of various sizes and shapes, she might just seen an improvement without having to restructure her house. Just some thoughts, [pre morning coffee] Paxmaha
________________________________ From: Steve Haflich <[email protected]> To: The Horn List <[email protected]> Sent: Fri, February 18, 2011 2:31:00 AM Subject: Re: [Hornlist] Acoustics and E Some might not recognize the solution in Klaus' linked picture. It is possible with a little effort to reduce the reverb and/or resonance in a room by applying rugs, drapes, other wall hangings, or coverings like egg-carton material to the flat surfaces of the room. Egg carton material is very good ad absorbing some important frequency ranges and is often found of the walls of chambers where acoustical measurements are being performed. Even a few pieces of stuffed furniture will have useful effect. An empty concert hall will respond somewhat more resonantly than a concert hall with an audience stuffed into the seats. However, the strategy of absorbing sound is not harmless, since it makes the room dead. Instruments generally sound better in a live room than a dead room. More specifically, in a live rehearsal space one can practice how to work with the reverb in a real hall, but one might not be able to hear all the details in one's playing. In a very dead rehearsal space one can hear every artifact or phrasing flaw in one's playing, which is useful and a learning experience, but somewhat removed from real playing. I believe that it is best if one can practice in bother kinds of spaces. One tells you how _good_ you can sound. The other tells you how bad you really sound, and what you might need to fix in order to sound how good you really _could_ sound. Phrasing, and breathing, and dynamics, and especially slurs, are all very different in these two environments. For an extreme exampy of places where your practice sessions wont sound very good, read http://en.wikipedia.org/wiki/Anechoic_chamber The first time I walked into an anechoic chamber, my knees almost buckled. The only time that has happened to me in the real world was hiking with my wife towards Carter Dome a little northeast and across the valley from Mt Washington in New Hampshire, when the path went down into a small bowl protected by the mountain flanks. There was no wind, no birds, no running streams, and there happened to be no airplanes within range. The mountains protected us from road noise. I suddenly told her to _stop!_ and we listened to absolutely nothing. Listening to nothing is an experience not to be missed. It gets harder and harder to do. _______________________________________________ post: [email protected] unsubscribe or set options at https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/paxmaha%40yahoo.com _______________________________________________ post: [email protected] unsubscribe or set options at https://pegasus.memphis.edu/cgi-bin/mailman/options/horn/archive%40jab.org
