Quote:
Originally Posted by
petertjed
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In some threads i came across the Invisible Alpha, but i can't find information about this system. Who can tell me more about this system?
Invisible Alpha© is an adjective I coined to make the use of sound absorption of walls and other partitions as integral part of the room acoustics design sound more fancy, mysterious, high tech and a great marketing/sales tool.
In its basic form
Invisible Alpha© refers to the low frequency absorption component of a an apparent wall or other hidden absorber. To a layman, a wall is a wall. The layman does not recognize the acoustic effects of the surface. As an example, 100 mm of 703 or equivalent material against a wall with a ~80 Hz mam resonance would have great absorption down to ~63 Hz. The low end absorption is invisible to the lay person.
Another example of partion absorption not being visible is the panel absorbers pioneered by Hidley and championed by Newell. A quote from Newell in Recordng Studio Design is in post #42
in this thread. Even with panel absorbers 1 m deep membrane (
Invisible Alpha©) absorbers are used the behind the panels for lowest frequency absorption.
Post #127
in this thread, is the first time I used
Invisible Alpha©.
The Alpha comes from Greek letter used to denote some forms absorption of materials.
Some time after the I first used
Invisible Alpha©, some discussions came about regarding getting even lower (frequency) absorption. I brought up the concept of using a triple leaf partition tuned to cover a wider deeper range of frequencies. Because the partition would use 2 air gaps (and I was having lots of with
Invisible Alpha©), I decided to call that design strategy
Invisible Alpha²©. In addition to appearing even more techy, fancy (dare I write it) sexy (well at least to acoustic geeks), and market savvy, it also challenges people to use character map even more. The dollar/euro/pound value is obvious if a cost analysis is done.
Invisible, sexy and cheap,
Andre