sone phons Dba and db
I was wondering the same thing
07-15-2009, 07:04 PM
#8
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So here's how you convert over:
1. Go to your favorite water hole.
2. Gather Female voluteers.
3. Test them.
4. Profit!
1. Go to your favorite water hole.
2. Gather Female voluteers.
3. Test them.
4. Profit!
The phon is a unit that is related to dB by the psychophysically measured frequency response of the ear. At 1 kHz, readings in phons and dB are, by definition, the same. For all other frequencies, the phon scale is determined by the results of experiments in which volunteers were asked to adjust the loudness of a signal at a given frequency until they judged its loudness to equal that of a 1 kHz signal. To convert from dB to phons, you need a graph of such results. Such a graph depends on sound level: it becomes flatter at high sound levels
07-15-2009, 07:06 PM
#9
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From Yahoo Answers:
http://answers.yahoo.com/question/in...3165147AAqImKs
First, some definitions.
dB(A) is the frequency weighted Sound Pressure Level (SPL) using the a-weighting network. This means that frequencies between about 1,000 and 6,000 Hz are attenuated up a hair (max is 1.3 dB at 2500 Hz) and all other frequencies are attenuated down (imagine a graph looking about like a half circle with the peak at 2500 Hz). This is done to more closely aproximate how a human ear percieves sound.
A Phon is define as 1 dB at a frequency of 1000 Hz and follows an equal loudness curve that tries to approximate human perception at different frequencies.
A Sone is defined at 40 Phon's.
The problem is that both the Phon and dB(A) are frequency weighted so trying to convert from one to the other is not (strictly) possible without the frequency content of the signals. There are, however, some look-up tables that get within about +/- 2 dB of being right. Using these 0.9 Sone winds up being about 28.2 dB(A).
Another factor you need to consider is the distance from the object at which the measurments were taken. In the free field, doubling the distance should cause a 6 dB drop in the SPL. Some results might show you the distance used, others might report what is called Sound Power which uses the above mentioned relationship between SPL and distance to estimate the SPL at the center of the object.
Good luck sifting through all the sound data. Personally I wouldn't buy from a company using Sone's since it's not an SI unit.
dB(A) is the frequency weighted Sound Pressure Level (SPL) using the a-weighting network. This means that frequencies between about 1,000 and 6,000 Hz are attenuated up a hair (max is 1.3 dB at 2500 Hz) and all other frequencies are attenuated down (imagine a graph looking about like a half circle with the peak at 2500 Hz). This is done to more closely aproximate how a human ear percieves sound.
A Phon is define as 1 dB at a frequency of 1000 Hz and follows an equal loudness curve that tries to approximate human perception at different frequencies.
A Sone is defined at 40 Phon's.
The problem is that both the Phon and dB(A) are frequency weighted so trying to convert from one to the other is not (strictly) possible without the frequency content of the signals. There are, however, some look-up tables that get within about +/- 2 dB of being right. Using these 0.9 Sone winds up being about 28.2 dB(A).
Another factor you need to consider is the distance from the object at which the measurments were taken. In the free field, doubling the distance should cause a 6 dB drop in the SPL. Some results might show you the distance used, others might report what is called Sound Power which uses the above mentioned relationship between SPL and distance to estimate the SPL at the center of the object.
Good luck sifting through all the sound data. Personally I wouldn't buy from a company using Sone's since it's not an SI unit.
http://answers.yahoo.com/question/in...3165147AAqImKs
Last edited by Superglue WRX; 07-15-2009 at 07:09 PM.
07-15-2009, 07:13 PM
#10
What is the coversion between Sone and Decibel (dB)?
This is a bit tricky to answer. The issue is that Decibels (dB) is an empirical measurement of the difference of sound pressure of two sounds. So to make standardized measurements of Decibels requires a room with a specific ambient sound pressure, a specific atmospheric pressure and a specific ambient temperature. This way Decibels provide the user with a reproducible experimental value that could then be experienced by the curious user. The Sone takes it a step further.
The Sone measurement is a numerical representation of a human's acoustic perception. This unit of perceived loudness was put into use after a proposal of S. S. Stevens in 1936. Since much of acoustics is important only in how humans react to the sound, it was seen fit that loudness be standardized. Loudness is a subjective measurement of the sound pressure, so one Sone was defined as equivalent to 40 Phons. Thereby one Sone equals the loudness of a 1 kHz tone at 40 dB SPL.
Now a Phon is also a unit of perceived loudness, but it is a subjective measurement of the strength (not intensity) of a sound. 1 Phon is defined to be equal to 1 dB SPL above the nominal threshold of hearing. The threshold of hearing is the sound pressure level (SPL) of 20 µPa (micropascals), equal to 2 x 10-5 pascals. Once you start measuring other frequencies in Phons it departs from the Decibel but is related to it by the frequency weighing curve (equal-loudness contour) that reflects the frequency response of human hearing. The standard curve for human hearing is the A-weighted curve, in use when indicated by the dB(A) notation.
The human auditory system is generally sensitive to frequencies in the range of 20 Hz to 20,000 Hz. The human ear is most sensitive in the range of 1,000 to 5,000 Hz due to the biomechanics of the ear. The equal-loudness contour (Fletcher-Munson curve) is a representation of the measure of sound pressure (dB SPL) versus the Frequency for which a listener perceives a constant loudness. The loudness is measured in Phons and by definition two sine waves of different frequencies that have equal Phons are equally loud.
Back to the Sone, the number of Phons equal to 1 Sone was chosen so that a doubling of the number of Sones is perceived by a human ear as a doubling of the loudness of the sound. This also corresponds to increasing the sound pressure level by 10 dB. When you are dealing with frequencies other than 1 kHz, the measurement in Sones must be calibrated according to the frequency response of human hearing.
Without a specified frequency, it will be difficult to precisely reproduce the perception of the measured loudness from just the Sones value; but a value of 0.5 Sones could be reproduced by generating a 1 kHz tone at 30 dB. By definition that tone would be of equal loudness to a tone of any other frequency correctly measured as 0.5 Sones. The actual decibel measurement of different frequency tones that are rated at 0.5 Sones will vary in correspondence to the equal-loudness contour.
It is also important to note that Decibels, being a logarithmic measurement, means that the perceived loudness of 20 Decibels is twice that of 10 Decibels. For example, while a Rock concert might be rated at 120 dB, a Jet Engine rated at 150 dB is perceived as 8 times as loud as the concert. As the Decibel is in reality a measurement between two quantities, it is a dimensionless unit, like a percentage. This makes Decibel measurements not as useful as people often assume. To be useful, it should have been applied to the equal-loudness contour and have a specified distance.
Equally, the Sone should also be paired with a specified distance and should be matched with a suffix G to specify that it was calculated from frequency groups and also be notated by the suffix F (free field) or D (diffuse field). If the frequency groups are provided with the Sone measurement, along with the other values - it should be possible to accurately reproduce the measured loudness. Source: Wikipedia
This is a bit tricky to answer. The issue is that Decibels (dB) is an empirical measurement of the difference of sound pressure of two sounds. So to make standardized measurements of Decibels requires a room with a specific ambient sound pressure, a specific atmospheric pressure and a specific ambient temperature. This way Decibels provide the user with a reproducible experimental value that could then be experienced by the curious user. The Sone takes it a step further.
The Sone measurement is a numerical representation of a human's acoustic perception. This unit of perceived loudness was put into use after a proposal of S. S. Stevens in 1936. Since much of acoustics is important only in how humans react to the sound, it was seen fit that loudness be standardized. Loudness is a subjective measurement of the sound pressure, so one Sone was defined as equivalent to 40 Phons. Thereby one Sone equals the loudness of a 1 kHz tone at 40 dB SPL.
Now a Phon is also a unit of perceived loudness, but it is a subjective measurement of the strength (not intensity) of a sound. 1 Phon is defined to be equal to 1 dB SPL above the nominal threshold of hearing. The threshold of hearing is the sound pressure level (SPL) of 20 µPa (micropascals), equal to 2 x 10-5 pascals. Once you start measuring other frequencies in Phons it departs from the Decibel but is related to it by the frequency weighing curve (equal-loudness contour) that reflects the frequency response of human hearing. The standard curve for human hearing is the A-weighted curve, in use when indicated by the dB(A) notation.
The human auditory system is generally sensitive to frequencies in the range of 20 Hz to 20,000 Hz. The human ear is most sensitive in the range of 1,000 to 5,000 Hz due to the biomechanics of the ear. The equal-loudness contour (Fletcher-Munson curve) is a representation of the measure of sound pressure (dB SPL) versus the Frequency for which a listener perceives a constant loudness. The loudness is measured in Phons and by definition two sine waves of different frequencies that have equal Phons are equally loud.
Back to the Sone, the number of Phons equal to 1 Sone was chosen so that a doubling of the number of Sones is perceived by a human ear as a doubling of the loudness of the sound. This also corresponds to increasing the sound pressure level by 10 dB. When you are dealing with frequencies other than 1 kHz, the measurement in Sones must be calibrated according to the frequency response of human hearing.
Without a specified frequency, it will be difficult to precisely reproduce the perception of the measured loudness from just the Sones value; but a value of 0.5 Sones could be reproduced by generating a 1 kHz tone at 30 dB. By definition that tone would be of equal loudness to a tone of any other frequency correctly measured as 0.5 Sones. The actual decibel measurement of different frequency tones that are rated at 0.5 Sones will vary in correspondence to the equal-loudness contour.
It is also important to note that Decibels, being a logarithmic measurement, means that the perceived loudness of 20 Decibels is twice that of 10 Decibels. For example, while a Rock concert might be rated at 120 dB, a Jet Engine rated at 150 dB is perceived as 8 times as loud as the concert. As the Decibel is in reality a measurement between two quantities, it is a dimensionless unit, like a percentage. This makes Decibel measurements not as useful as people often assume. To be useful, it should have been applied to the equal-loudness contour and have a specified distance.
Equally, the Sone should also be paired with a specified distance and should be matched with a suffix G to specify that it was calculated from frequency groups and also be notated by the suffix F (free field) or D (diffuse field). If the frequency groups are provided with the Sone measurement, along with the other values - it should be possible to accurately reproduce the measured loudness. Source: Wikipedia
Last edited by kspek; 07-15-2009 at 07:15 PM.
07-15-2009, 08:36 PM
#12
for the love of god thank you
even the smart person explanation is confusing at time
im not going to graph crap!
thanks crazy kid thats what i got from kspec's post
and of coarse superglue thanks now i have a good guestamate to go on
ive never heard of sone and phon before today
even the smart person explanation is confusing at time
im not going to graph crap!
thanks crazy kid thats what i got from kspec's post
and of coarse superglue thanks now i have a good guestamate to go on
ive never heard of sone and phon before today
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