^ "EU Sound Power Regulation for Vacuum Cleaners".^ "ISO 3744:2010(en) Acoustics - Determination of sound power levels and sound energy levels of noise sources using sound pressure - Engineering methods for an essentially free field over a reflecting plane".^ "ISO 80000-8(en) Quantities and Units - Acoustics".Clinical Measurement of Speech and Voice. The sound pressure used in the calculation may be affected by distance due to viscous effects in the propagation of sound unless this is accounted for. The sound power estimated practically does not depend on distance. Sound power, denoted P, is defined by P = f ⋅ v = A p u ⋅ v = A p v For omnidirectional sources in free space, sound power in L wA is equal to sound pressure level in dB above 20 micropascals at a distance of 0.2821 m Situation and Here is a table of some examples, from an on-line source. The required environment is on hard ground in a large open space or hemi-anechoic chamber (free-field over a reflecting plane.) The test environment can be located indoors or outdoors. Measurements in accordance with ISO 3744 are taken at 6 to 12 defined points around the device in a hemi-anechoic space. The A-weighting scale is used in the calculation as the metric is concerned with the loudness as perceived by the human ear. Devices (e.g., a vacuum cleaner) often have labeling requirements and maximum amounts they are allowed to produce. L WA specifies the power delivered to that surface in decibels relative to one picowatt. Regulations often specify a method for measurement that integrates sound pressure over a surface enclosing the source. The complete sound sounds like it's out of phase.Maximum sound power level ( L WA) related to a portable air compressor. If I use all measuring positions (believe I have 6 or 9). And the more measurements I take, the further the sound seems to shift. Could you please give me some pointers ? And I have read all the guides on mic positioning etc. I like my center stage to be dead center on my listening position. Same goes for music in stereo mode (obviously). I've redone the automatic setup so many times, but I never get the result I'm looking for. It works a little but not the way I'd like it to be. So to try and compensate I tried lowering the level of the right speaker to shift the center image more to the middle of my seating position. The voices in music appear to be coming more from the right speaker. The problem I then get is that when music in a 5.1 mix is transmitted stereo through the two front speakers it doesn't appear to be coming from the center position as I would like. but that's not an actual listening position on the couch. to the right of the first position about 2 ft. I then for the second measurement move the mic (have it on a boom/mic stand). So that was my first seating position for measuring. It's placed against a wall and I always sit on the left side of the couch. My couch is on center between my speakers. But I'm having some trouble with Dynamic EQ. Why does it have to be so ridiculously loud ?Īnother question, not sure if this is the right topic. If I play at reference level I'm at 82% of my amps power! This will literally make me dead in about 20mins. I understand the reference setup, although all mixers must be deaf by now.
0 Comments
Leave a Reply. |