Music and outdoors: are they meant to work together?
Outdoor spaces, or very large venues for that matter, often offer a seducing way of hosting large events without undue complications regarding security and fittings. However, they usually do not provide the audience and the performers with as high a level of comfort than enclosed venues. More to the point, community noise control of such facilities can really be tricky. What can be expected of such facilities? This paper intends to submit a few hints, looking at recent projects and developments.
Inside Out – Time Variant Electronic Acoustic Enhancement Provides the Missing Link for Acoustic Music Outdoors
No matter how good the acoustic ensemble, moving them from the concert hall to an outdoor stage dramatically changes the listening experience for both the musicians, and those in attendance – usually, not for the better. For the musicians, the loss of reflected and reverberant energy alters communication between members of the ensemble. The physiology of playing the instrument changes as well – without support from reflected and reverberant energy, musicians must compensate. Thus while the outdoor performance experience of may be deemed “good” for both those playing as well those listening, it is not the experience that either desire. This paper describes how time variant electro-acoustic enhancement has been successfully used to dramatically improve the acoustical musical experience for outdoor performance.
Modeling Coherent Backscattering Errors in Fiber Optic Gyroscopes for Sources of Arbitrary Line Width
We present a new model of the noise and drift induced by coherent backscattering in a fiber optic gyroscope (FOG) interrogated with a light source of arbitrary temporal coherence. This study is critical to understand whether a FOG driven with a laser instead of a broadband source can attain high sensitivity and stability, which would have the overwhelming benefit of improving the FOG scale factor stability by at least ten-fold and would enable the use of FOGs for inertial navigation of aircrafts. Analytical and numerical solutions bring to light two significant new predictions. First, coherent-backscattering noise can be made negligibly small by utilizing a laser with a very narrow linewidth (less than ~ 20 kHz), although in this regime the drift is high. Second, by using a laser with a broad linewidth (greater than ~ 10 MHz), both the noise and the drift are low enough for aircraft inertial navigation. The dependencies of the noise and drift on fiber loss, loop coupling coefficient, and backscattering coefficient are also presented to define the optimum mode of operation of this new class of FOGs.