The Flaw in Fletcher-Munson Curve

[markthevirtuoso]

I came across an interesting find while surfing the net. This issue wasn't really introduced when we studied Equal Loudness Contours (i.e. Fletcher-Munson and Robinson-Dadson effects) in class. Actually, I am quite surprised knowing that I have to somehow modify (for lack of better term) my understanding towards it. Maybe some of you might be interested in it so I thought i'd share.

Behold audiophiles!

http://sound.westhost.com/project17.htm

[zach lucero]

intresting...... ganun talaga, audio pa. A lot try to measure what they hear, and hear what they can't measure....

[KitC]

Very profound, Zach. I find it very unusual that scientists have an easier time quantifying the qualities of light while sound seems to baffle them.

[markthevirtuoso]

intresting...... ganun talaga, audio pa. A lot try to measure what they hear, and hear what they can't measure....

Very profound, Zach. I find it very unusual that scientists have an easier time quantifying the qualities of light while sound seems to baffle them.

Amen to these sirs!

[skunkyfunk]

Nice points sirs.  I just wonder how we can add flaming to this thread as I see F-M in the thread title. 

[superwup]

I love to read that but i can not open any page containing sound.westhost

Maybe because im from the "province"? 

I did did try my internet options etc. but still not be able to open any sound.westhost.com  page/ article

[xjepoyx]

Nice points sirs.  I just wonder how we can add flaming to this thread as I see F-M in the thread title. 

hahaha natawa ako dun ah hehe

[Tarkuz Toccata]

I came across an interesting find while surfing the net. This issue wasn't really introduced when we studied Equal Loudness Contours (i.e. Fletcher-Munson and Robinson-Dadson effects) in class. Actually, I am quite surprised knowing that I have to somehow modify (for lack of better term) my understanding towards it. Maybe some of you might be interested in it so I thought i'd share.

Behold audiophiles!

http://sound.westhost.com/project17.htm

There's no flaw in F-M Curve! Low-cost audio equipment often list an A-weighted noise spec -- not because it correlates well with our hearing -- but because it helps "hide" nasty low-frequency hum components that make for bad noise specs. Sometimes A-weighting can "improve" a noise spec by 10 dB. Words to the wise: always wonder what a manufacturer is hiding when they use A-weighting.

[KitC]

Nice points sirs.  I just wonder how we can add flaming to this thread as I see F-M in the thread title. 

Easy....


Just add Line6 POD. 

[markthevirtuoso]

There's no flaw in F-M Curve! Low-cost audio equipment often list an A-weighted noise spec -- not because it correlates well with our hearing -- but because it helps "hide" nasty low-frequency hum components that make for bad noise specs. Sometimes A-weighting can "improve" a noise spec by 10 dB. Words to the wise: always wonder what a manufacturer is hiding when they use A-weighting.

Firstly, I was being rhetoric. I apologize if it seems misleading.

Secondly, my critical understanding, as far as the recent field researches are concerned, infers that it really has a flaw. The FM curve relates to the subjective loudness of pure tones only. Sure, maybe the study was somehow revised upon the introduction of the Robinson-Dadson curve. But even this focused mainly on studying pure tones separately. The problem is do speakers react the same way as these two studies have concluded in a practical environment, where pure tones are out of context? How much change does our hearing perception undergo upon the existence of harmonic distortion at different levels? I think that is the flaw - the context in which this particular theory is applied.

Why it is still considered to be the standard (in the US especially) when concerned authorities have already acknowledged the FM and RD limitations is still a puzzle to me. Besides, BBC (UK) suggests a better study - the ITU-R 468 noise weighting, that is.



Some more insights here
http://www.lindos.co.uk/cgi-bin/FlexiData.cgi?SOURCE=Articles&VIEW=full&id=2


 

[markthevirtuoso]

Nice points sirs.  I just wonder how we can add flaming to this thread as I see F-M in the thread title. 

 

[abyssinianson]

Very profound, Zach. I find it very unusual that scientists have an easier time quantifying the qualities of light while sound seems to baffle them.

because a photon is much easier to quantify using standardized equipment than it is to quantify something like sound which has many parameters AND is further complicated by a compensatory mechanism in the auditory system. as a scientist, the more parameters in a focal point of study, the more cr@p I have to deal with to understand it...it kinda makes you want to smash your equipment when it reports confounding results.

[BAMF]

because a photon is much easier to quantify using standardized equipment than it is to quantify something like sound which has many parameters AND is further complicated by a compensatory mechanism in the auditory system. as a scientist, the more parameters in a focal point of study, the more cr@p I have to deal with to understand it...it kinda makes you want to smash your equipment when it reports confounding results.

Honga.

Even in Telecoms, the quality of a speech signal is weighted using the unit of Mean Opinion Scores (MOS). Which is to say that a signal is judged my many listeners who judge it based on intelligibility and other factors. So, it's still subjective, unlike the photon which can be measured with units that do not require human intervention.