[jessica00]

its EXACTLY why we have EQ's, that and for ever so slight bass boosts.

 

[fredpb]

Quote:

Originally posted by bobzemuda I strongly disagree with this!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Your ears can't hear it, but your body can feel it. I guess it might not apply as much to headphones as it would to a full stereo system, but your body can feel those extended frequencies. As I've mentioned before, I tape concerts. In that application, the extended frequencies that your body can feel lend the recordings a since of "being there." Another instance, would be a techno/dance club. They'll hit you with low end because you can not only hear it, but you can feel it. Bill

I would agree with this. I am sure your body can sense frequencies you can't really "hear". How about the deaf dancers that "feel" the vibrations?

Also, what is a "freq response"? What does the manufacturer mean by 20-20k? Flat response? Or does the manufacturer say in fine print 20-20khz (+- 12 db). Big difference.

And what about a CD? freq response to 20K???? But up their, there sound/samples are pretty chopped up compared to a 50hz waveform. CD's CAN sound good, but they are usually mastered like crap, that is, they stink, soundwise.

A home recorded CD of a TELARC LP (classical) sounds wonderful, but the EXACT same work on a pre recorded CD stinks.

All in the specs. All in the implementation. All in the variables.

And there is a lot more to high end audio sound than freq response and distortion measurements.

 

[JaZZ]

Quote:

Originally posted by engk: I could easily hear the 20 khz wav file. I guess this tells me to stay away from any phone that only does 20-20 khz.

It's not that dramatic! Since the CD format is restricted to that range, you won't get more than that either way. And if you think of FM radio with its upper end at 15 or 16 kHz, there are actually only few high frequencies missing with a good tuner, although noise and distortion prevent it from being a high-end source. And after all you wouldn't be happy with the Etymotic ER-4s, which have an equal bandwidth, but in fact sound very pleasing.

Data sheets aside, a wide bandwidth with sound transducers is advantageous, not primarily to enable ultrasound, but to provide a better transient response within the audible frequency range. But I think such is hard to achieve with headphones. The reason is their closeness to the ears: that way there are a lot of interferences between the sound from the center and the one from the edge of the diaphragm, which have different delays and besides have to struggle with reflections on the outer ear which cause additional interferences – all of this contributing to an attenuation or even obliteration of highest frequencies.

But I think the high-frequency resproduction of the best headphones is very satisfying, independent from their measured bandwidth.

JaZZ

 

[engk]

That sucks. I was going to post something on that, whether cds deliberately reduced the frequency range to save "space". Is that true that they rectified this in sacds?

 

[d_wilson]

The ER-4's don't stop working at 16kHz. 16kHz is the reasonable limit on the test format used. We are using an ANSI standard ear simulator for our tests. The acoustic impedance of the coupler drops off dramatically after 16kHz. Even when testing the $10,000+ Orpheus on this system (using the whole manequin)you will have the same problem.

There is no problem below 20 Hz, but there is no reason to advertise them below normal human hearing.

Don Wilson
Etymotic Research

I do recall studies where they found was that people were actually hearing sub harmonices of the +20kHz sounds.

 

[JaZZ]

Quote:

Originally posted by d_wilson The ER-4's don't stop working at 16kHz. 16kHz is the reasonable limit on the test format used. We are using an ANSI standard ear simulator for our tests. The acoustic impedance of the coupler drops off dramatically after 16kHz. Even when testing the $10,000+ Orpheus on this system (using the whole manequin) you will have the same problem.

So it's pure modesty that your specification goes that way:

20 Hz to 16 kHz +/- 4 dB?


But actually the graph on your website even doesn't look like this:

All models seem to reach (at least almost) 20 kHz. Otherwise there's the other graph measured with the Zwislocki coupler in which the frequency response in fact dropps off above 16 kHz:

Both graphs don't seem to represent the acoustic reality to me (fortunately), rather something inbetween.

JaZZ

 

[Tim D]

Ety freq specs is coupled with db variance rating, it is different and a little bit more revealing than something you'd find reading off specs for a Sony earbud. Even 888's will sport a ridiculously broad frequency range and they are rolled off, if not will eventually become rolled off. And no where on the specs will you read "frequency response will eventually turn to mush".

These and other headphones/earphones are just passive vibrating tranducers...there is nothing to stop it from reproducing high frequencies. It is the performance of said frequencies that matters which is not ever indicated much by these freq range specs. Frequency response range is a typically meaningless marketing spec, especially without any db rating as given in so many other consumer devices. This has been discussed countless of times before.

Although I'm sure the Panasonic DVD phones do have a broader frequency range with their "super tweeters", from what I've heard, it doesn't do much and it seems like they should be trying to get the frequency response *right* instead of *wide*.

If you look at *any* of the hi-end headphones frequency response charts in the high end done by even headroom, you will notice there seems to be no phone able to actually do flat response above 16khz, much less below that. Getting a transducer to merely respond to high frequency signals is easy, getting it to reproduce a flat coherent and SMOOTH high frequency signal seems much harder. In fact this is probably why headroom needs to implement so much smoothing in their data is because of high freq variance.

 

[JaZZ]

Tim...

...I'm not orientated to frequency response specs – rather to frequency response graphs. I just wonder why Etymotic Research uses the worst possible response for their specs: 20 Hz--16 kHz -4 dB, which obviously marks the upper end, according to the corresponding (lower) graph. From this proceeding I deduce the consideration that this is the response ER takes for the acoustically relevant one.
Quote:

These and other headphones/earphones are just passive vibrating tranducers...there is nothing to stop it from reproducing high frequencies.

A membrane with an electric drive is far from being «passive». And since there are a moving mass and acoustic effects such as interferences and cavity effects, there are clearly restrictions to the frequency response.

 

[Tim D]

I was suggesting that the Ety's with what I would figure to be extremely small mass in its diagphram, would have no problem responding to high frequencies as far as the requirements of reproducing 20khz cycles, just as I'm sure many a cheap earbud could. I think however when it comes to bass response, than there are a lot of physical limitations of headphones which Ety's overcome with a good seal, however as far as high frequencies go, it seems to me that most modern headphones with lightweight and small drivers can reproduce high frequencies to lesser or greater extents(which unfortunately are *not* indicated by frequency response specs).

My only intention was that some people seem to have the impression that an earphone or headphone will all of the sudden not respond what so ever to a high frequency signal if it isn't mentioned in spec. I think for the most part, any decent transducer should be able to "respond" it is wheter or not it is responding correctly that matters. And some companies are much more liberal in what they consider a correct response.

I've heard high frequency tones with Ety's and just wanted to dispel the myth that the transducers will simply lay silent after it reaches beyond the 16khz point.

I am sure there are plenty of other variables beyond just getting a diapghram to cycle at high frequencies in order to actually get those high frequencies into your ear as intended.

My post was more in-line with the original discussion of the meaning of frequency response stats, not fr graphs.

 

[Eagle_Driver]

Last night (or was it early this morning?) I tested several closed headphones with that downloaded tone generator - and paying particular attention to the 20Hz tone. I've tested the Sennheisers HD 212Pro and HD 280Pro, and Sony MDR-7506 and MDR-V700DJ - with the TAH/EJ1000 portable rig set with the volume normalized to the 1kHz tone. I was shocked to find that the V700DJ barely delivers enough 20Hz output to even FEEL, let alone hear! (But the 100Hz tone was loud!) And even the 30Hz tone is weaker from the V700DJ than with the other headphones that I've tested - including two open-air Sennheisers (HD 497 and HD 600) that I've thrown in as a check. The Sony 7506 is as expected, but the surprise came with the Sennheiser 280!

The 280 actually reproduces an audible (and not just felt) 20Hz tone (though the 'audibility' of that bass might have been 'resonance spasms'), especially with an amp. And both the 280 and the 7506 easily delivers felt 20Hz bass even directly from the headphone-out of my Panasonic CT790 PCDP. The 212's bass extension falls in between the V700 and the 7506, based on my analysis.

 

[setmenu]

In a sealed headphone enclosure surely the very lowest
frequency's should be detectable ,if the volume of air is correct and the seal good as the volume is being compressed,all be it
slowly.
I can detect the air movement in my staxs from very low frequency's on a 0-22k sweep.[boy does that DC sound good

]
With a 10 hz signal I do hear a modulating very deep tone.
Perhaps at this low frequency even if I am not supposed to hear
one,my brain thinks,hey the my ears are detecting a modulation
in sound pressure! So it must make a noise like this.
my Lf response is different in both ears one being unable to detect that 10hz tone,so that makes me wonder ....



Setmenu

 

[Ubijza]

Well, according to a physics professor from my university:
1. Vynil is a much better source then CD. Frequency range of good LP recording stretches all the way to 60 000Hz (yes, not a missprint - 60KHz)... compared to 20Khz (or something similarly low) for CD. CDs are MP3s of LPs - if you know what I mean

(that's digital revolution for ya: crappy digital tv, crappy digital radio, crappy digital music

)
2. People cannot hear past such-n-such frequencies blah-blah-blah... RUBBISH!!! We can not hear a full tone,but harmonics/overtones and such can be heard u to and around 50kHz range. This explains why piano, violin music sound flat and muffled on the CD - harmonics of these instruments are particularly rich and inedequacy of "CD revolution" is especially apparent.

 

[bigshot]

A lot of audiophools put great stock in the frequencies beyond "20 to 20", but the truth is, the closer you get to the edges of audibility, the less discerning the ear is. Just because you can perceive something at 24hz, it doesn't mean that it's important to the music. I know a lot of people take pride in announcing that they can detect frequencies that only bats can hear, but when it comes right down to it, those frequencies don't make a lick of difference to whether something sounds good or not.

95% of what we humans listen to in music falls between 100hz and 12khz. If that range is flat and clean, it doesn't matter if it gets a little dodgier beyond that. Forget what the graph says... your ears are what you hear with. Ears don't lie, but frequency response graphs can be fudged. Some manufacturers rate their equipment at 16hz to 24khz (+or-12db). That looks swell on paper, but you aren't going to hear the frequencies that fall to -12db, and you have much less a chance of hearing them if they're on the edge of your ears' ability to hear. If there's a frequency in the middle that's +12db, that's all you're going to hear... it'll mask all the frequencies around it.

The reason that manufacturers play this game is that they want you to worry and obsess about those numbers... "Gee! Maybe my headphones aren't reproducing 19khz cleanly... I better get new ones!" That's sucker bait. Don't let them manipulate you, and don't encourage others to be manipulated. Trust your ears, not numbers. If you follow that advice, your system will sound just as good to you, and you'll end up saving thousands of dollars.

See ya
Steve

 

[bigshot]

Quote:

Originally Posted by Ubijza This explains why piano, violin music sound flat and muffled on the CD - harmonics of these instruments are particularly rich and inedequacy of "CD revolution" is especially apparent.

Hooey!

There are great sounding piano and violin CDs and lousy sounding ones. The difference between the two has a lot more to do with the size of the room and the microphone choice and placement than it does the frequency response.

As for the frequency response of vinyl reaching to 60khz... the only sonic information you might be able to measure at ranges above 20khz is surface noise. Your physics prof should know better, because the frequency response of the 24 track open reel deck that they recorded the album on doesn't reach anywhere near as high as he is talking about. How could the vinyl contain information that isn't on the master?

See ya
Steve

 

[bigshot]

Those test tones are interesting. I used to work for the company who produced Alvin & the Chipmunks, and I supervised the recording sessions. I was constantly in pain during playback. They used to make fun of me because I was always sticking tissues in my ears. Those tones told me what was going on... I can hear to 19khz, but it's excruciatingly painful at anything but a low volume. I can't hear anything, but I still feel pain at 20khz. I get the same feeling in some department stores with banks of flourescent lights overhead.

See ya
Steve