Topic: "Lossy Audio (MP3) can harm your health"
Taken from another forum, writen by "trux":
ok, i'm on a mission. i wan't to get the world clean of lossy audio (for music-listening at least).
why?
1: it sounds shitty. and yes, you can hear the difference too, don't believe the industry saying you cannot!
i really wonder how the industry can dictate our perception to such a degree.. same as back in the 80s, when they claimed the CD bringing HiFi to new levels, and everyone believed them, and heared 'how clear it sounds'.
2: it has an impact on the kind of music that get's produced, and how it is produced. and that's not good for ppl who try to produce music with a 'long-time-value', believe me.
3: there are theories out there, that listening to lossy audio (MP3, Ogg, etc..) can harm your hearing abilities!!!
how? well, i try to put it short and simple:
basics:
How does your hearing work?
->sound-waves in the air reaching your eardrum and cause it to vibrate
-> mechanism of bones transmit these vibrations to your cochlea (a liquid-filled conical tube, with neuronal vibration-sensing 'hairs-cells' alongside)
-> the soundwaves propagate through this 'tube' and each frequency produces 'standing waves' on a certain spot in the tube, regarding to the changing diameter. thus, each frequency stimulates a certain set of 'hair-cells'. this is the point, where physical vibrations are transformed into neuronal stimulations.
-> you do not percive this stimulations directly!! your brain (neuro-acoustical system) filters out alot of unwanted noise before giving you any perception. this is called 'masking' (f.e. intense sounds mask sounds with lower intensity in a certain freq-band, sounds coming from the direction you face mask sounds that come from other directions (cocktail-party-effect), sound that arrives first mask sound that comes in delayed (up to ~0.63 ms), ...)
-> after your brain filtered out alot of noise, it finally provides you the 'perception of sound', which is actually only a fraction of the soundwaves that hit your eardrum..
-> without this neuro-acoustic system, we would all go dizzy and crazy, bombed down by huge amounts of useless noise..
How does lossy audio work?
knowing that the neuro-acoustic system filters out alot of the sound that hits the eardrum, engineers and scientists had the idea (smart they are):
let's filter all the inaudible noise out upfront and save some bandwith!
that's the basic idea behind lossy audio. algorithms vary in quality and techology, but they all try to cut away, what they assume to be inaudible anyway.
How can that harm your hearing abilities?
the human brain needs to adapt and learn all the time. this is ofc also true for your neuro-acoustic system. if you don't feed 'unwanted noise' to your brain, it could, over time, loose the ability to filter it out itself. the general 'adapting-training' of your brain get's skipped, and that can cause alot of nasty symptoms. there are medical studies that show an increase of tinitus since the implementation of lossy audio, also more and more ppl showing up with strange symptoms (they can't hear directional anymore, everydays life 'sounds like MP3', acoustic stimulance makes them feel dizzy, and so on..). most of them pass the classical frequency vs amplitude hearing-test, so the problems lie inside the neuro-acoustic system, not in the mechanical hearing-system (which usually gets harmed by high SPL-levels)
What should we do?
use lossy audio for short-term listening only (previewing music, cell-phone-ringtones, computer-game-sound-samples) but not for listening to music! get a CD, DVD-Audio or vinyl (or a flac-file, non tarnsscripted ffs) of your music!
most of all: use your ear to judge sound-quality and STOP BELIEVING the AUDIO-INDUSTRY!!! you can hear the difference, even with the fraunhofer-algorhitm set at best bit-rate!! trust yourself!!
if you spent loads of money on your HIFI, spend some on music too! you would waste alot of money if you used your hifi for MP3s..
think about it again: do you really need 50k songs on your harddrive, most of them you'll never listen too? or 50 full albums on your ipod? 10 years ago, we were happy with a MC-walkman and 5 cassettes in our backpack!
do your brain a favour, and purchase music that you like!
regards, trux
PS: many of the 'facts' i presented here are what i read in a scientific paper a while ago. unfortunately i cannot find it anymore for referencing. please also note, that the 'facts' are not confirmed, as, for now, the industry is not willing to pay for further studies of the issue.
also note: i used the term 'neuro-acoustic', which i made up of my own. the topic is commonly called 'psycho-acoustics', a term that i try to avoid, because all the psychedlic freaks thinking about frequencies that stimulate colorful caleidoscope visions when catching the term 'psycho-acoustic' lol