The Propagation of Low Frequency Sound Through an Audience by Elena Shabalina (E

Description: The Propagation of Low Frequency Sound Through an Audience by Elena Shabalina Estimated delivery 3-12 business days Format Paperback Condition Brand New Description At large outdoor concerts or festivals subwoofers, the dedicated low frequency loudspeakers, are often placed in a row in front of the stage as an evenly spaced array in order to control the directivity of sound at low frequencies. The audience itself often stands tightly packed in front of the array, so that sound waves propagate partly through the audience and partly over it. This thesis presents an investigation on how exactly the presence of the audience influences the propagation of sound. A mathematical model of an audience as an equivalent fluid is constructed with the help of the porous medium theory. The equivalent fluid parameters, such as the wave impedance, the speed of sound and the reflection coefficient from the audience/air boundary, are calculated both for a constant and a variable concentration of an audience. The model is verified by a Boundary Element Method simulation, scale measurements and live concert measurements. A new live measurement method is developed to evaluate the low frequency sound pressure level distribution without disturbing the ongoing event.The study reaches the conclusion that at low frequencies an audience forms a medium with the impedance significantly different from the impedance of the air, which leads to the reflection of sound waves from the boundaries back into the audience and increase of the sound pressure level as well as interference effects. Possible applications of the findings are mainly sound system design and event planning. Details ISBN 3832536086 ISBN-13 9783832536084 Title The Propagation of Low Frequency Sound Through an Audience Author Elena Shabalina Format Paperback Year 2014 Pages 77 Publisher Logos Verlag Berlin GmbH GE_Item_ID:137249731; About Us Grand Eagle Retail is the ideal place for all your shopping needs! With fast shipping, low prices, friendly service and over 1,000,000 in stock items - you're bound to find what you want, at a price you'll love! Shipping & Delivery Times Shipping is FREE to any address in USA. Please view eBay estimated delivery times at the top of the listing. Deliveries are made by either USPS or Courier. We are unable to deliver faster than stated. International deliveries will take 1-6 weeks. NOTE: We are unable to offer combined shipping for multiple items purchased. This is because our items are shipped from different locations. Returns If you wish to return an item, please consult our Returns Policy as below: Please contact Customer Services and request "Return Authorisation" before you send your item back to us. Unauthorised returns will not be accepted. Returns must be postmarked within 4 business days of authorisation and must be in resellable condition. Returns are shipped at the customer's risk. We cannot take responsibility for items which are lost or damaged in transit. For purchases where a shipping charge was paid, there will be no refund of the original shipping charge. Additional Questions If you have any questions please feel free to Contact Us. Categories Baby Books Electronics Fashion Games Health & Beauty Home, Garden & Pets Movies Music Sports & Outdoors Toys

Price: 74.54 USD

Location: Fairfield, Ohio

End Time: 2024-11-14T04:45:36.000Z

Shipping Cost: 0 USD