Hearing damage with headphone usage

our ears are the most sensitive to 4khz sound...so...that'd probably damage our hearing the easiest

The sound pressure level of a sound is what damages your hearing not the frequency. When the SPL reaches a certain level coupled with time your hearing will be damaged. Having a low frequency sound at 110 dB will damage your hearing as will a high frequency tone at an spl of 110 db.

For some interesting reading follow this link to The Physics of Music:

http://physics.mtsu.edu/~wmr/P160_open.htm

I don't think that logic makes sense; but I don't actually know what frequencies are most likely to cause damage. Anyone have a link about this?

Here is why I don't think we should use that logic. Consider eyesight.... The eye is damaged differently by different wavelengths. Let's ignore UV, which is absorbed in and damages the cornea. In the visible range, the deep blue end of the spectrum is far more likely to cause lesions in the retina (leading eventually to senile macular degeneration) than the red end of the spectrum. But there isn't much deep blue that reaches our eyes.

The deep blue isn't as easy to perceive as is the middle of the visible spectrum. When we are out in the sunlight, or iris closes down, and we squint (plus there is a longer-lasting chemical change that also reduces sensitivity). These mechanisms help avoid damage by the deep blue.

However, most dark glasses do not attenuate the blue end of the spectrum very much (users like blue glasses, unfortunately). They attenuate the part of the spectrum that we are most sensitive to. As a result, dark glasses actually increase the amount of deep blue that reaches our eyes, and increase retinal damage.

By analogy, it is quite possible that by amplifying music, we may create more damage from the low frequency part of the spectrum. Ironically, we could receive more damage from those wavelengths to which we are least sensitive.

I do know that impact noise is very damaging. I'm told that we tend to suffer hearing loss near 4 kHz because there is a bend in the Cochlea that corresponds with this part of the spectrum; shock waves essentially bash into this bend. This suggests to me that perhaps displacement is the source of damage, hence that low frequencies may be the most damaging.

I am sure of this: the hearing frequency for which sensitivity is damaged over time is determined by our anatomy, not by the frequency of sound that we are exposed to. Whatever we are exposed to, we lose hearing aroud 4-6kHz.

I don't think sight and hearing can be compared. They work in two different ways entirely. It is the energy in a sound wave that can cause damage. I think what might be confusing is that it is easier to generate a low frequency sound that is damaging than it is to get that same energy in a high frequency sound.

Of course I wasn't comparing. I was using an analogy to show why the second post in the thread might be misleading. Our eyes are least sensitive to deep blue, but that is the wavelength that damages our retina the most, especially at high altitudes. This is why eagles have yellow filters that cover the eyes (that, and better visual acuity, esp. under glary conditions).

I'll look for more answers to the original question if I have time. I didn't see the third post in the thread before clicking "submit," so I'll go read it now....

Below 100Hz it takes a lot more SPL to damage your hearing. The mid and high range frequencies are much more damaging at a given SPL (above 90db.) There are a whole host of issues when it comes to headphones and hearing damage but I don't feel like typing them out now.

It is higher frequencies. From 3-4khz on up. Part of it is simple
fatigue in the hair cells of the inner ear that register the sound.
A haircell moves back and forth alot more when tuned for
several kilohertz than it does for lower frequencies. Which
eventually 'wears it out'.

This is paraphrasing many details. But the info comes from a basic
recent textbook on hearing inteneded for undergraduate classes.

High frequencies are worse, but any frequency loud enough or loud enough long enough will cause damage.

If you look at the ears construction, the cillia nearest the eardrum are those responsible for the high frequencies. They are also those closest to the ear drum and those that get exposed to the greatest effects from loud noises. This is why folks tend to lose the upper end of their hearing first. Based on this I would GUESS that the ear can be damaged more by high frequency noises, but I've never seen an expert state this.

I think the most important thing to consider is total exposure to sound. Even if bass is less dangerous, it is delusive becasue a high level of bass is not perceived as equally high as a 4 kHz tone with the same amplitude.
According to the Swedish working environment regulations the maximum level of exposure is 85 dB during eight hours a day. This is the same dose of exposure as 88 dB during four hours, or 91 dB during two hours. If you already are exposed to this dose, you should avoid to add exposure to traffic noise, music etc. Other countries should have similar limits.

I beleive some (many?) headphone listeners expose themselves to much more than this!

Higher frequency info causes more hearing damage than low end stuff. To my recollection bass doesn't and can't cause any damage below something like 120Hz or so. No matter what the volume. That one guy drives around in a van with about 145dB worth of bass playing and NO hearing protection. According to OSHA he should be deaf or dead in something like 1 minute at that volume, but here is is to this day driving around listening to his music that loud.

The problem is that unless you EQ all the other frequencies to lower them WAY below the bass, listening to actual music at high volumes will cause damage and evantually hearing losses.

Also, since your ears react to sound by reducing the voume which you actually hear it is best to start low and stay there. Most engineers in recording studios us especially tuned rooms with a very flat response and VERY low volumes so that they can hear the entire range equally without having your ears shutdown and cause a weird shift in the response of your ears' frequency response curve. I have my music so low every single person who listens to my cans after me has to turn them up quite a bit before they like the sound level. I have gotten to like the music much lower and in a safe enough range to listen all day every day without risk.

The Am. Med. Assoc. states that prolonged exposure to noise at or above 90 decibels will damage hearing, especially high pitched noise (high pitched is not defined as to frequency, but assume 3-5,000 Hz). Hearing loss is cumulative, so someone can be hearing really loud music now and exposed over a period of time, may seemingly not have any damage. But, in years to come the damage will catch up with them causing problems as they grow older.

Also, any excessively loud noise at any frquency will cause damage if exposure is long enough. If any of you have ever seen a loudest car contest where the contestants have to stay out of the vehicle, tape down/reinforce windows and doors to keep them from coming loose, have helpers push in on doors and windows to keep them from opening, etc. to prevent the loss of sealing and thus lowering sound pressure levels - well that sound pressure is not being created by 4"/6"/'6"x9" tweeters/mid-range speakers for the most part. Rather it is a bunch of 12", 15", 18" and larger sub-woofers creating the bulk of the sound pressure (or noise in decibels). I have seen pressure levels exceed 145 dB in these contests and exposure to this level of sound exposure will eventually lead to hearing loss that may not be apparent now.

Last, the Am. Med. Assoc. warns that personal stereo sound levels should not be loud enough to be heard by others around them.

Damage to your ears is cumulative and the damage is irreversable. Many a rock star suffers from permanent hearing damage - as do afficienados who play their stereos too loud or use headphones at high volume levels.

Moderation in sound levels when you are young should lead to the enjoyment of music for many years. The alternative . . .

If high frequencies damage hearing first,
could this mean that really bright headphones have more potential to cause hearing damage?

IMO, that depends on how loud you listen to the bright headphones since hearing damage is based on higher volume/sound pressure. The AMA states that too loud higher frequencies do cause more damage. However, damage can occur from too loud music/noise in any frequency range.

It would seem that bright cans would not need to be played at higher volume levels to hear the higher frequencies versus laid-back cans or cans with dips in the higher frequencies that cause people to increase volume levels to hear the higher frequencies (go to HeadRoom and look up some graphs for say Senn. 580/600 or AKG 1000 to see the high frequency dips). I would venture to say that laid-back cans and/or cans with high frequency dips that are played at higher volume levels to hear the dips in the higher frequencies coupled with the resulting even higher volumes for those frequencies ranges not suffering from dips would be more harmful versus cans with relatively flat frequency response played at lower volume levels such that all the details of the music can be heard about the same as laid-back cans and/or cans with dips. However, I would also believe that cans with low frequency emphasis and/or dips in lower frequencies would also be harmful when the volume is turned-up too loud to compensate. Prolonged excessive sound pressure is what causes hearing damage whether high or low frequencies - albeit that excessive sound pressure from high frequencies will do the most damage according to the AMA.

Hearing damage is cumulative over time, so any one listening session is not going to result in easily detectable permanent hearing damage (unless you are talking about one session of really loud music/noise for a long enough period of time), but exposure to too loud music/noise long enough in enough individual sessions will result in permanent hearing damage sometime in the future.

FYI, the military has researched/developed sound weapons based on highly amplified low frequencies that reportably can do serious damage to structures and humans.

I know that changing the cord on my 590's helped remove a dip in the higher frequencies and resulted in not having to play them at higher volume levels to hear the dip frequency range because the frequency response was closer to being flat.

This brings a whole new side to the sennheiser "veil" debate. If you hear sennheiser veil then you are losing your hearing.

I can already read the next senn vs whatever debate. "What you hear as veil is really just you going deaf. That probably also explains why you like the whatevers more than the 600s."