Resource Documents by Pedersen, Christian Sejer

Møller, Henrik; and Pedersen, Christian Sejer
Hearing at low and infrasonic frequencies 
Abstract. The human perception of sound at frequencies below 200 Hz is reviewed. Knowledge about our perception of this frequency range is important, since much of the sound we are exposed to in our everyday environment contains significant energy in this range. Sound at 20-200 Hz is called low-frequency sound, while for sound below 20 Hz the term infrasound is used. The hearing becomes gradually less sensitive for decreasing frequency, but despite the general understanding that infrasound is inaudible, humans . . . Complete article »

Pedersen, Christian Sejer; Møller, Henrik; and Pedersen, Steffen
Low-frequency noise from large wind turbines – additional data and assessment of new Danish regulations 
Summary. Previous studies have shown that the noise has more low-frequency content, when wind turbines get larger, and with todays’ megawatt turbines the low-frequency noise may cause annoyance for the neighbours. Therefore, low-frequency noise has been included in the noise regulations on wind turbines in Denmark. In this study, the data material has been increased to include more data on noise from modern production turbines up to 3.6 MW. In addition, the new Danish regulations are assessed. The previous result that . . . Complete article »

Møller, Henrik; and Pedersen, Christian Sejer
Low-frequency noise from large wind turbines 
[Abstract] As wind turbines get larger, worries have emerged that the turbine noise would move down in frequency and that the low-frequency noise would cause annoyance for the neighbors. The noise emission from 48 wind turbines with nominal electric power up to 3.6 MW is analyzed and discussed. The relative amount of low-frequency noise is higher for large turbines (2.3–3.6 MW) than for small turbines (≤ 2 MW), and the difference is statistically significant. The difference can also be expressed as a downward . . . Complete article »

Marquardt, Torsten; and Pedersen, Christian Sejer
Cochlear anatomy shapes sensitivity to low-frequency sounds 
[abstract] In accordance with standards on hearing, sound sensitivity is assumed to decrease smoothly as frequencies approaches infrasound. However recently, non-invasive measurements of the forward-middle-ear-transfer function (fMETF) in human subjects reveal a resonance feature near 55 Hz, where the slope changes rather sharply by 6 dB per octave. These transfer characteristics of the pressure in the ear canal to the differential pressure across the basilar membrane are presumably caused by the shunting effect of the helicotrema – a small connection . . . Complete article »

Pedersen, Christian Sejer; and Møller, Henrik
Analysis of low frequency noise from large wind turbines 
[abstract] As wind turbines get larger, worries have emerged, that the noise emitted by the turbines would move down in frequency, and that the contents of low-frequency noise would be enough to cause significant annoyance for the neighbors. The sound emission from 48 wind turbines with nominal electric power between 75 kW and 3.6 MW was analyzed. The apparent sound power, LWA, increases with electric power at a rate close to 3 dB per doubling of electric power. The low-frequency proportion . . . Complete article »

Pedersen, Christian Sejer
Human hearing at low frequencies, with focus on noise complaints 
Summary The human hearing is generally not sensitive at low-frequencies and relatively high sound pressure levels are needed before the sound is audible. However, if the sound is audible then slight changes in the level gives relative large changes in the perception of the sound which is reflected in the compression of the equal-loudness-level contours at low-frequencies. Combined with individual differences in the hearing function with possible extraordinary low-frequency hearing this could explain cases where only one person in the . . . Complete article »

Also try:
Search all of documents for "Pedersen, Christian Sejer".
Search entire site for "Pedersen, Christian Sejer".