Changes and Challenges in Environmental Noise Measurement * Philip J Dickinson Massey University Wellington, New Zealand
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Definition and Measurement of Sound Energy Level of a Transient Sound Source
J. Acoust. Soc. Jpn. (E) 8, 6 (1987) Definition and measurement of sound energy level of a transient sound source Hideki Tachibana,* Hiroo Yano,* and Koichi Yoshihisa** *Institute of Industrial Science , University of Tokyo, 7-22-1, Roppongi, Minato-ku, Tokyo, 106 Japan **Faculty of Science and Technology, Meijo University, 1-501, Shiogamaguti, Tenpaku-ku, Nagoya, 468 Japan (Received 1 May 1987) Concerning stationary sound sources, sound power level which describes the sound power radiated by a sound source is clearly defined. For its measuring methods, the sound pressure methods using free field, hemi-free field and diffuse field have been established, and they have been standardized in the international and national stan- dards. Further, the method of sound power measurement using the sound intensity technique has become popular. On the other hand, concerning transient sound sources such as impulsive and intermittent sound sources, the way of describing and measuring their acoustic outputs has not been established. In this paper, therefore, "sound energy level" which represents the total sound energy radiated by a single event of a transient sound source is first defined as contrasted with the sound power level. Subsequently, its measuring methods by two kinds of sound pressure method and sound intensity method are investigated theoretically and experimentally on referring to the methods of sound power level measurement. PACS number : 43. 50. Cb, 43. 50. Pn, 43. 50. Yw sources, the way of describing and measuring their 1. INTRODUCTION acoustic outputs has not been established. In noise control problems, it is essential to obtain In this paper, "sound energy level" which repre- the information regarding the noise sources. -
Monitoring of Sound Pressure Level
1. INTRODUCTION Noise is one of the main environmental problems of modern life and it is inseparable from human activities, urban and technological growth. National and international standards provide for a minimum of acoustic comfort for coexistence between man and industrial development. That's why a study of noise emission and environmental noise at the PALAGUA - CAIPAL Field was carried out; samples of measurements were taken in specific (punctual) manner to meet the sound pressure level (SPL) with a duration of five minutes per sample/measurement for noise measurements and 15 minutes for ambient or environmental noise in each direction: (north, east, south, west and vertical). The result of these measurements was compared with the maximum permissible noise emission and environmental noise standards stated in Resolution 627 of 2006 Ministry of Environment, Housing, and Territorial Development (MAVDT) and thus it was verified that they comply with environmental regulations in the PALAGUA - CAIPAL Field. 1 INFORME DE LABORATORIO 0860-09-ECO. NIVELES DE PRESIÓN SONORA EN EL AREA DE PRODUCCION CAMPO PALAGUA - CAIPAL PUERTO BOYACA, BOYACA. NOVIEMBRE DE 2009. 2. OBJECTIVES • To evaluate the emission of noise and environmental noise encountered in the PALAGUA - CAIPAL Gas Field area, located in the municipality of Puerto Boyacá, Boyacá. • To compare the obtained sound pressure levels at points monitored, with the permissible limits of resolution 627 of the Ministry of Environment, SECTOR C: RESTRICTED INTERMEDIATE NOISE, which allows a maximum of 75 dB in the daytime (7:01 to 21:00) and 70 dB in the night shift (21:01 to 7: 00 hours) 2 INFORME DE LABORATORIO 0860-09-ECO. -
Noise Exposure Limit for Children in Recreational Settings: Review of Available Evidence
Noise exposure limit for children in recreational Make Listening Safe settings: review of WHO available evidence This document presents a review of existing evidence on risk of noise induced hearing loss due to exposure to sounds in recreational settings, with respect to children. The evidence was used to stimulate discussion for determination of exposure limits (in children) to be applied to standards for personal audio devices. The review has been undertaken by February 2018 Dr Benjamin Roberts under the supervision of Dr Richard Neitzel, in collaboration with WHO. The document has been reviewed by members of WHO expert group on exposure limits for NIHL in recreational settings. Noise exposure limit for children in recreational settings: review of available evidence Authors: Dr Benjamin Roberts Dr Richard Neitzel Reviewed by: Dr Brian Fligor Dr Ian Wiggins Dr Peter Thorne 1 Contents List of Tables 1 List of Figures 1 Definitions and Acronyms ............................................................................................................................. 2 Executive Summary ....................................................................................................................................... 3 Background and Significance ........................................................................................................................ 4 How Noises is Assessed............................................................................................................................. 5 Overview of the Health -
NQ-A4060, NQ-A4120, NQ-A4300 4 Channel Audio Power Amplifiers
4-Channel Audio Power Amplifiers Configuration Manual NQ-A4060, NQ-A4120, NQ-A4300 2019 Bogen Communications, Inc. All rights reserved. 740-00099D 191101 Contents List of Figures ............................................................................... v List of Tables .............................................................................. vii Configuring the Four-Channel Audio Power Amplifiers 1-1 1 Using the Dashboard ..............................................................................3 2 Updating Firmware ..................................................................................4 3 Setting Network Tab Parameters .......................................................6 4 Setting Configuration Tab Parameters ............................................8 5 Accessing Log Files ............................................................................... 10 6 Setting DSP Parameters ...................................................................... 13 6.1 Setting the Channel Level .................................................. 15 6.2 Signal LED, Clip LED, and VU Meter .............................. 15 6.3 Muting a Channel ................................................................. 16 6.4 Adjusting Volume Levels ................................................... 16 6.5 Adjusting Compression Settings .................................... 16 6.6 Adjusting the Graphic Equalizer ..................................... 18 6.7 Setting High/Low Pass Parameters ................................ 20 6.8 Adjusting -
PRODUCT CATALOG Home Control - Loudspeakers - General Products NAVIGATION CATALOG
PRODUCT CATALOG Home Control - Loudspeakers - General Products CATALOG NAVIGATION Products are grouped by category of interest. Sections are differentiated by color coding on the bottom right of each page. HOME CONTROL Multi-room audio control, now with lighting and climate, plus remote access. Page 4 LOUDSPEAKERS Architectural audio solutions where you live, work, and play. Page 27 GENERAL PRODUCTS Complete the connected experience here. Page 85 2 CALL 1-800-BUY-HIFI – www.nilesaudio.com 3 HOME CONTROL A Heritage of Recognition The Niles name is synonymous with premier whole home audio solutions. For nearly four decades, Niles has delivered innovative products that enable simple and easy access to home entertainment, and we are now creating audio solutions that seamlessly integrate with lighting and climate control. Niles products enable custom integrators to design and install systems that deliver truly exceptional entertainment solutions for customers. 4 Home Control HOME CONTROL SOLUTIONS Auriel - One Touch to Control . 6 MRC-6430 Multi-Room Controller . 12 nTP7 Touch Panel .....................14 nTP4 Touch Panel .....................15 nKP7 Keypad .........................16 nHR200 Remote Control. 17 SYSTEMS INTEGRATION AMPLIFIERS® 16-Channel Amplifier . 20 12-Channel Amplifier . 21 2-Channel Amplifiers . 22 CALL 1-800-BUY-HIFI – www.nilesaudio.com Home Control 5 One Touch to Control. Niles Auriel now adds built-in streaming audio, plus climate and lighting control to the award-winning multi- room audio platform. The result is an exceptional home control experience. The wizard whisks you through simple decisions that quickly configure the system for lighting scenes and thermostat programming, audio sources, zone preferences, user interface customization and home theater control. -
15W Stereo Class-D Audio Power Amplifier
TPA3121D2 www.ti.com SLOS537B –MAY 2008–REVISED JANUARY 2014 15-W STEREO CLASS-D AUDIO POWER AMPLIFIER Check for Samples: TPA3121D2 1FEATURES APPLICATIONS 23• 10-W/Ch Stereo Into an 8-Ω Load From a 24-V • Flat Panel Display TVs Supply • DLP® TVs • 15-W/Ch Stereo Into a 4-Ω Load from a 22-V • CRT TVs Supply • Powered Speakers • 30-W/Ch Mono Into an 8-Ω Load from a 22-V Supply DESCRIPTION • Operates From 10 V to 26 V The TPA3121D2 is a 15-W (per channel), efficient, • Can Run From +24 V LCD Backlight Supply class-D audio power amplifier for driving stereo speakers in a single-ended configuration or a mono • Efficient Class-D Operation Eliminates Need speaker in a bridge-tied-load configuration. The for Heat Sinks TPA3121D2 can drive stereo speakers as low as 4 Ω. • Four Selectable, Fixed-Gain Settings The efficiency of the TPA3121D2 eliminates the need • Internal Oscillator to Set Class D Frequency for an external heat sink when playing music. (No External Components Required) The gain of the amplifier is controlled by two gain • Single-Ended Analog Inputs select pins. The gain selections are 20, 26, 32, and • Thermal and Short-Circuit Protection With 36 dB. Auto Recovery The patented start-up and shutdown sequences • Space-Saving Surface Mount 24-Pin TSSOP minimize pop noise in the speakers without additional Package circuitry. • Advanced Power-Off Pop Reduction SIMPLIFIED APPLICATIONCIRCUIT TPA3121D2 1m F 0.22m F LeftChannel LIN BSR 33m H 470m F RightChannel RIN ROUT 1m F 0.22m F PGNDR PGNDL 1m F 0.22m F LOUT BYPASS 33m H 470m F AGND BSL 0.22m F PVCCL 10Vto26V 10Vto26V AVCC PVCCR VCLAMP ShutdownControl SD 1m F MuteControl MUTE GAIN0 4-StepGainControl GAIN1 S0267-01 1 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. -
Sound Waves Displacement
Producing sound waves Displacement 1.4 Sound Density Pressure Producing sound waves Speed of sound •Sound waves are longitudinal •Produced by compression and rarefaction of media (air) Energy and Intensity resulting in displacement in the direction of propagation. • The displacements result in oscillations in density and pressure. Spherical and Plane waves. Frequencies of sound wave Speed of sound Speed of sound in a fluid B infra-sonic Audible Sound v = ultra- sonic ρ ∆P B =− Bulk modulus 10 20,000 ∆V/V m Frequency (Hz) ρ= Density V Similarity to speed of a transverse wave on a string 30 0.015 Wavelength (m) in air elastic _property v = int ertial_property Speed of sound in air γP B v = v = ρ ρ γ is a constant that depends on the nature of the gas γ =7/5 for air Density is higher in water than in P - Pressure air. ρ -Density Why is the speed of sound higher in water than in air? Since P is proportional to the absolute temperature T by the ideal gas law. PV=nRT T v331= (m/s) 273 1 Energy and Intensity of sound waves o Find the speed of sound in air at 20 C. energy power P = time T area A v331= 273 273+ 20 v== 331 343m/ s 273 For calculations use v=340 m/s power P intensity I = = (units W/m2) area A Sound intensity level The ear is capable of distinguishing a wide range of sound intensities. The decibel is a measure of the sound intensity level ⎛⎞I What is the intensity β=10log⎜⎟ decibels of sound at a rock I ⎝⎠o concert? (W/m2) -12 2 Io = 10 W/m the threshold of hearing note- decibel is a logarithmic unit. -
Measurement of Total Sound Energy Density in Enclosures at Low Frequencies Abstract of Paper
View metadata,Downloaded citation and from similar orbit.dtu.dk papers on:at core.ac.uk Dec 17, 2017 brought to you by CORE provided by Online Research Database In Technology Measurement of total sound energy density in enclosures at low frequencies Abstract of paper Jacobsen, Finn Published in: Acoustical Society of America. Journal Link to article, DOI: 10.1121/1.2934233 Publication date: 2008 Document Version Publisher's PDF, also known as Version of record Link back to DTU Orbit Citation (APA): Jacobsen, F. (2008). Measurement of total sound energy density in enclosures at low frequencies: Abstract of paper. Acoustical Society of America. Journal, 123(5), 3439. DOI: 10.1121/1.2934233 General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. WEDNESDAY MORNING, 2 JULY 2008 ROOM 242B, 8:00 A.M. TO 12:40 P.M. Session 3aAAa Architectural Acoustics: Case Studies and Design Approaches I Bryon Harrison, Cochair 124 South Boulevard, Oak Park, IL, 60302 Witew Jugo, Cochair Institut für Technische Akustik, RWTH Aachen University, Neustrasse 50, 52066 Aachen, Germany Contributed Papers 8:00 The detailed objective acoustic parameters are presented for measurements 3aAAa1. -
Power Demystified Garth Powell
Power Demystified Garth Powell 2621 White Road Irvine CA 92614 USA Tel 949 585 0111 Fax 949 585 0333 www.audioquest.com Contents Introduction AC Surge Suppression AC Power Conditioners/LCR Filters AC Regeneration AC Isolation Transformers DC Battery Isolation Devices with AC Inverters or AC Regeneration Amplifiers AC UPS Battery Backup Devices AC Voltage Regulators DC Blocking Devices for AC Power Harmonic Oscillators for AC Power AC Resonance/Vibration Dampening Power Correction for AC Power Ground Noise Dissipation for AC Power Appendix: Some Practical Matters to Bear in Mind I. Source Component and Power Amplifier Current Draw II. AC Polarity III. Over-voltage and Under-voltage Conditions Index Introduction The source that supplies nearly all of our electronic components is alternating current (AC) power. For most, it is enough that they can rely on a service tap from their power utility to supply the voltage and current our audio-video (A/V) components require. In fact, in many parts of the world, the supplied voltage is quite stable, and if the area is free of catastrophic lightning strikes, there are seemingly no AC power problems at all. Obviously, there are areas where AC voltage can both sag and surge to levels well out of the optimum range, and others where electrical storms can potentially damage sensitive electrical equipment. There are many protection devices and AC power technologies that can ad- dress those dire circumstances, but too many fail to realize that there is no place on Earth that is supplied adequate AC power for today’s sensitive, high-resolution electronic components. -
Exploding the Efficiency Myth of Class D Amplifiers Much Has Been Written About the Efficiency of Class D Amplifiers, with Figures of 90% Or Greater Routinely Quoted
Exploding the efficiency myth of AS-100204-WP Issue 1 Class D amplifiers Exploding the efficiency myth of Class D amplifiers Much has been written about the efficiency of Class D amplifiers, with figures of 90% or greater routinely quoted. Such numbers might seem to suggest that the efficiency problem of audio amplifiers has been well-solved by conventional Class D. However, a closer look shows that this is far from the truth, with these amplifiers frequently seeing only single-digit percentage efficiencies, or less, in real product usage conditions. To address this problem, a new generation of audio amplifier solutions has just emerged, heralding a massive reduction in average power consumption. The problem Figure 1 shows a plot of efficiency versus power output for a typical Class D amplifier, but plotted with a logarithmic power axis, rather than the linear scale invariably seen in data-sheets. Sure enough, the top right of the graph, corresponding to maximum power output, shows the efficiency reaching almost 90%. However, in typical consumer usage, an audio amplifier hits its rated maximum power comparatively rarely – only when the volume is turned right up to the onset of clipping. Even then, maximum power is reached only on the loudest audio peaks, which make up a relatively small proportion of typical content. Across the operating life of an amplifier, it is seen that average power output typically sits at around 20 to 50dB below full scale, a massive 100 to 100,000 times in linear power terms, as we now explore. At this comparatively tiny output level, corresponding to the lower left region of Figure 1, the efficiency of the conventional Class D solution is seen to be disappointingly low. -
Daat Power Amplifier White Paper
ISP Technologies patented Dynamic Adaptive Amplifier Technology™ Audio power is the electrical power off the AC line transferred from an audio amplifier to a loudspeaker, measured in watts. The power delivered to the loudspeaker, based on its efficiency, determines the actual audio power. Some portion of the electrical power in ends up being converted to heat. Recent years have seen a proliferation in what is called specmanship at a minimum and outright fabrication of misleading specifications at worst. The bottom line is power amplifier ratings are virtually meaningless today since there is no standard measurement system in use. This leads to confusion and serious misunderstanding in the audio community. ISP Technologies has for years rated the D-CAT power amplifiers in true RMS output power and as a result have shown modest performance specifications when compared with competitive amplifiers or self powered speakers. Some manufactures have gone so far as to claim they are offering 20,000 watt RMS power amplifiers with power consumption off the line on the order of 30 amps. I would like to see the patent on this amazing technology since there would be countless power companies beating a path to their door to license this technology. This white paper has been written to help shed some light on different types of power amplifier technologies and realistic and actual power amplifier power performance ratings and to also explain the advantages of the new ISP Technologies DAA™ Dynamic Adaptive Amplifier™ Technology now in use by ISP Technologies. An audio power amplifier is theoretically designed to deliver an exact replica of an audio input signal with more voltage and current at the output. -
Investigating Electromagnetic and Acoustic Properties of Loudspeakers Using Phase Sensitive Equipment
Investigating Electromagnetic and Acoustic Properties of Loudspeakers Using Phase Sensitive Equipment Katherine Butler Department of Physics, DePaul University ABSTRACT The goal of this project was to extract detailed information on the electromagnetic and acoustic properties of loudspeakers. Often when speakers are analyzed only the electrical components are considered without taking into account how this effects the mechanical operation of the loudspeaker, which in turn directly relates to the acoustic output. Examining the effect of mounting the speaker on a baffle or in an enclosure is also crucial to determining the speaker’s sound. All electrical and acoustic measurements are done using phase sensitive lock in amplifiers. By analyzing the speaker in such a detailed manner, we can ultimately determine which properties really affect the overall tonal qualities of that speaker. I. Background and Introduction attracted to or repelled by the permanent magnetic field. The moving parts of the The loudspeaker is the most important speaker, the driver, can then turn link in any audio chain. It is the last electrical energy into acoustic energy. piece of equipment the audio signal The electrical components of the speaker passes through before we hear anything. have a certain resonance when the You may have the best amplifier money electrical impedance is greatest. The air can buy, but that means nothing without surrounding the speaker and propagating quality speakers. In the audio chain the sound also has its own resistance to speakers are composed of some of the motion, radiation impedance. simplest electric circuits; it is the quality of manufacturing and physical design that is most important in speaker quality.