[Davesrose]

Well no matter what decay is supposed to be here....treble notes get to your ear drum faster then bass notes, simply because the sound frequency is higher. I'm assuming that's what nothing101 is getting at. That's why treble seems faster then bass. I think it gets to be a perception thing when some point to a bright headphone and say it has no bass. I've heard some say that the HD595 has no bass.....but I hear plenty of bass. Either they're deaf in the bass department, or their senses are overwhelmed with the treble that they don't perceive as much bass. Could be differences in the shapes of our ears too. One thing's for sure.....all of our hearing is different!

 

[nothing101]

i think percussion changes frequency as it looses energy. not sure about other instruments though.

 

[miscreant]

Quote:

Originally Posted by nothing101 i think percussion changes frequency as it looses energy. not sure about other instruments though.

percussion is an instrument?

 

[nothing101]

well its a group of instruments, i was generalising.

 

[miscreant]

the biggest group..

 

[nothing101]

im sick of arguing with you people.. i just want to point out that this only effects bass and two the changes in frequency are only slight as is the muting effect from bass rolloff. Our ears as soo well tuned to time that we really hear more accurately in that aspect of sound than we hear any other. (only my opinion so dont have a fit)

our brains will interpret sounds in more comlex ways than we may understand but from what i hear at the extremes i could be fooled into thinking that 20hz is 30 hz but just a bit less loud.

I think that we arent as good at defining the extremes as we are at defining the mids. Thats because in nature there isnt really all that much bass but the sound that mattered to us was the mids and some of the highs. i think this is what shaped our hearing and why its difficult to hear differences in bass

 

[Asr]

No offense intended, but from reading the replies some people here clearly don't know what attack and decay are. Attack & decay should not be mistaken for forwardness, or extended treble, or whatever, etc. "Attack" does not refer to "impact" as most people might think it does. Most people's perception of what "impact" means is actually part of the mid-range response, and varies with the instrument.

Here's a good short explanation of both: http://en.wikipedia.org/wiki/ADSR_envelope

 

[miscreant]

dont be sick. just be accurate. then you can argue with some people.
our ears are tuned to the real world. the headphoning is an attempt to mimic that...is not possible. your opinion is always somewhat right.

 

[miscreant]

oh i wanna glossary here, please.

 

[Davesrose]

I am losing you nothing101 if you're insisting that soundwaves can actually change wavelengths in air.....that would defy the fundamental prinicples of thermodynamics IMHO. The only time a wavelength canges would be when it encounters another medium and tranfers energy. When a soundwave loses energy, it's amplitude is going down.
http://en.wikipedia.org/wiki/Amplitude

Asr's link says that attack and decay are measurements of the intensity of volume on a given note or instrument. Volume is amplitude. Lets say it's a piano key that's struck. The instant it strikes the string, that sends off the biggest aplitude in sound. The attack. The decay are the reverberations of the string.

Treble can appear faster then bass, because it has many more ossilations in it's wave. Your eardrum is getting many more waves of a high pitched note vs the long wavelenths of a low pitched note. That's the main principle why treble appears fast. Another is our ear lobes. They help us with spacial location. They're spiral shaped to funnel sound, as well as actually amplify some waves that are directly in front of us. So it's taking longer for the bass notes to vibrate our eardrums:
http://en.wikipedia.org/wiki/Pinna

So from an evolutionary standpoint....we needed our sense of bass to survive!!! It's a much better indicator of sources then treble. It can also travel further since it's wavelengths are farther apart.

A frequency response graph shows us how well a speaker produces a certain ocillation at a given volume. When you look at FRG of headphones, none of them can produce the really deep bass. If you look at the 501, it has a gradual arch throughout its mid frequencies. Grados ,on the other hand, have some massive fluctuations in the lower mids as well as the treble region. This rise in amplitude would account more for it's reproduction of a note's attack and decay at a given frequency (impact). Looks like I'd better check out those Grado SR 225s sometime....their FRG actually has quite a bit of bass!

 

[miscreant]

and there's another trick with hearing - wiki: The middle-ear is able to dampen sound conduction a bit when faced with very loud sound by noise induced reflex contraction of the middle ear muscles.

in real world there are not so many cases (room reverb and ambient sound helps to avoid that), but if you listen music with headphones you bet it happens on almost every note.

 

[Davesrose]

I would think for the real world your stapes muscles would clamp down during really loud music concerts, jet planes, anything over 90-100 db. Hopefully I'm not listening loud enough for them to be working too much while listening to headphones!

Quote:

Originally Posted by miscreant and there's another trick with hearing - wiki: The middle-ear is able to dampen sound conduction a bit when faced with very loud sound by noise induced reflex contraction of the middle ear muscles. in real world there are not so many cases (room reverb and ambient sound helps to avoid that), but if you listen music with headphones you bet it happens on almost every note.

 

[miscreant]

that is an interesting subject. cant find a decent article thoug...

 

[imported_Matt_Carter]

Quote:

Originally Posted by nothing101 Ive been looking at the frequency response graphs at headroom and i think ive realised what is the cause of unnaturally quick highs. As a note looses energy and decays it gets a longer wavelength so when the lower frequency sounds are muted the last part of the decay of bass is muted and this creates a fast feel that grados have. This is becase grados ARE badly extended in the lows. i think it is deliberate. More evidence to back up this theory is that people have said that the agk 501 has impact like grado and what do you know, its bass is like quieter grado bass in terms of frequency response graphs. My conclusion in this is that a bit of roll off in bass might be a good thing as it will appear to make the bass as fast as the absolute sound even though thats impossible. Too much of this and your headphone may sound bassless and too fast in bass. Too much low end bass will also make the headphone sound slower. I think its all about balance

Your theory makes sense and im glade to see some real logical thinkers here instead of just know it all's.
But I think the cure would be to find a way to mange impedance across the entire range. less resistance in the low end, and crazy high impedance for highs. which would emulate a natural decay.

Grados are a prime example of everything done WRONG

 

[Davesrose]

But decay has nothing to do with high or low frequencies

Quote:

Originally Posted by Matt_Carter But I think the cure would be to find a way to mange impedance across the entire range. less resistance in the low end, and crazy high impedance for highs. which would emulate a natural decay.