[kelly]

If you can't or won't use Stax then I concur with the recommendation of Grado HP-1000 first and Etymotic ER-4S second.

 

[Hirsch]

The packaging of the HP-1 does not give a frequency range, and the Ety definitely does not go as high as is needed. I do not think the HP-1 has the high frequency extension of the RS-1, but that's a subjective guess.

The MS-Pro is probably the closest to neutral of those dynamic headphones that have the frequency extension you need. Someone else will have to say whether there's a Beyer with that kind of extension that is also neutral.

 

[smokey]

Depending on how important your requirements for frequency extension are, I might suggest the Panasonic RP-FDA100. This phone uses two drivers, including a tweeter. The claimed frequency response is 3hz-100khz. This is from the announcement on Headwize,

"Panasonic/Technics has created headphones specifically for listening to the high quality audio of SACDs and DVDs. The model RP-FDA100 has 2-way transducers (57mm woofer and 20mm tweeter) with a frequency response extending well into the ultrasonic range (3Hz to 100kHz). The light weight (11.3 oz) and self-adjusting headband make these headphones comfortable to wear for long periods. The 10-foot, user-replaceable headphone cord will automatically detach if it gets caught on furniture or other objects. Specs: 32 ohms impedance, open-type enclosure, 100dB/mW sens., 1000mW max. power handling. It retails for about $350 US."

There are reviews on the net in a variety of languages. I couldn't find a graph to see how flat that frequency response was, but it couldn't hurt to do a little digging.

Good Luck!

 

[BenG]

Seems like the ER-4B would be better than the ER-4S/P for the use described. Although +10 KHz would be in question for any of the ERs.

HD-600 - you have to be freakin' kidding. Maybe for research of audiophile fantasies.

 

[kelly]

RS-1 is certainly brighter than HP-1. If your goal is to hear treble detail at the expensive of a balanced frequency response I suppose that's something to consider but that's not what I thought the poster was asking for.

ER-4B likewise, is brighter than ER-4S. According to Etymotic, the ER-4S has a flat frequency response under normal room conditions and the ER-4B should be used with binaural recording because they were recorded without room interaction in mind. I've only heard the ER-4S--the frequency response seems accurate to me. According to Vertigo, the ER-4B is flat and the ER-4S is dark along with almost every other headphone and amp.

 

[halcyon]

Thanks for the responses so far. I did a little bit more digging on the net.

I found the following clues:

Replacement headphones for psychoacoustic testing (Bob Carlyon, 1998)
http://www.auditory.org/postings/1998/238.html
- Recommends Lambda Pro, Sennheiser HDA200, Sennheiser HD250 linear 2

Sony MDR V6 no good (nor many others with a shared common ground, unless modiefied?)
http://www.auditory.org/postings/1996/127.html

Sennheiser HD414 (old classics of psychoacoustic labs, not made anymore)
http://www.auditory.org/postings/1996/14.html

Sennheiser HDA 200 audiometric headphones
http://www.sennheiser.com/sennheiser...ssionals_02994
- For this calibration data measuerd in: Han, L. A and Poulsen, T.: (1998): Equivalent threshold Sound Pressure Levels (ETSPL) for Sennheiser HDA 200 earphone and Etymotic Research ER-2 insert earphone in the frequency range 125 Hz to 16 kHz. Scand. Audiol. vol. 27, p. 105-112

Reliability of hearing thresholds
http://www.vard.org/jour/01/38/5/pdf/flick.pdf

Sennheiser HE60 (with a proper matchin amp that can drive it to 65 kHZ) would be ideal. Many places are now trying to find these headphones for their use. Of course, they are silly expensive for this purpose (as most stats are for me).

It seems though that most of the headphones are :

- measured with artificial ear (i.e. taking into the non-linearities, in order to measure just noticeable differences and calibrate to reference levels by excluding many ear related personal differences. HOwever, this is not what I'm after).

However, I'm still very much in the learning phase - so further comments are welcome.

regards,
Halcyon

PS If anybody wants to sell their HE60 set, here's your chance:

http://www.auditory.org/postings/2002/226.html

 

[Tomcat]

halcyon,
if I understand correctly, you're problem seems to be that headphones (and even monitoring or high-end headphones) that sound flat are not what you're after. You want something that measures flat. But virtually all headphone designs take head-related transfer functions (HRTF) into account and try to equalize the sound in some way. The Stax Lambda Pro that you mentioned, for example, has been specifically designed in order to achieve a diffuse field equalization if I remember correctly. This limits your options to audiometric headphones or headphones designed for listening to binaural recordings. But since audiologists aren't too concerned about hearing loss above 15kHz, audiometric headphones will not give you the treble extension you're looking for, up to 30 or 40 kHz.

Another thing: it's misleading to directly compare frequency specs of hi-fi headphones since they are doctored by different marketing divisions. One manufacturer's 5 Hz to 30 kHz might be with a -10dB tolerance on a sunny day, another one's 50 Hz to 15 kHz might be at -1dB even in a hurricane.

 

[Hirsch]

Quote:

Originally posted by kelly RS-1 is certainly brighter than HP-1. If your goal is to hear treble detail at the expensive of a balanced frequency response I suppose that's something to consider but that's not what I thought the poster was asking for. ER-4B likewise, is brighter than ER-4S. According to Etymotic, the ER-4S has a flat frequency response under normal room conditions and the ER-4B should be used with binaural recording because they were recorded without room interaction in mind. I've only heard the ER-4S--the frequency response seems accurate to me. According to Vertigo, the ER-4B is flat and the ER-4S is dark along with almost every other headphone and amp.

The original poster asked for a frequency response out to 30KHz. If you look at the Etymotic site, they only go out to 18-20 KHz. While the RS-1 certainly errs on the side of brightness, both it and the MS-Pro, which reportedly is closer to neutral, have a frequency response rated out to the 30 KHZ requested by the original poster. Joe Grado did not supply a frequency rating with the HP-1. It's presentation suggests to me that the high end may top out lower than the RS-1. That's no reflection on its quality, as I think you know my opinion of that. Simply, there's no way to know if it will meet the original request, and would cost a lot of money to speculate on.

 

[JaZZ]

halycon...

...I'm still not quite sure what you want. There is no headphone frequency response independent of the ear and its necessarily individual shape/non-linearities. Any measurements through an artificial ear (weighted, if need be) come closer to the hearing impression than without it – whatever the measurement conditions thereby may be.

Probably we could help you more if we knew more about your intentions. What's the exact purpose of this? You had ultrasound on your wish list, but then you're considering yourself some «audiometric» headphones which barely reach 12 kHz...

And meanwile the well-meant propositions have reached a downright electrostatic price level – without any objection of yours, who originally limited the price range to affordable dynamic types... I would clearly prefer electrostatic headphones for your plans, regarding linearity as well as extension. Why should now a HP 1000 go for an ideal audiometric sound source and not any Stax for the same price?

JaZZ

 

[halcyon]

Tomcat:

"if I understand correctly, you're problem seems to be that headphones (and even monitoring or high-end headphones) that sound flat are not what you're after."

Yes. At least I seem to thinks so (a working hypothesis).

I need a sound source that is as neutral as possible as a sound source. This means NOT taking into account (at least not A LOT) generic head and outer ear related transfer functions.

It doesn't need to SOUND neutral to the test subject (it hardly will), but it needs to produce a neutral response from a test signal BEFORE that sound enters the ear canal (or even pinna or reflects from head).

Of course this means taking into account some of the head & headphone coupling related sound colorations, but it is complicated not to overdo it as pinna is part of this equation and VERY personal (i.e. hard to make generic functions about it).

If you look at the field of psychoacoustics a lot of it seems to concerned with what happens with certain kind of excitation if that excitation exists at near the tympanic membrane.

Hence, these tests usually take into the head/ear related non-linearities and try to compensate for them IN ORDER to produce a desired kind of pressure signal at the tympanic membrane.

I don't want this. I want the ear / head to distort the signal the way it naturally does (differing with each test subject). Just like with loudspeakers.

Before you yell "but loudspeaker are different", I will agree with you.

The problem is finding a sound source that is NOT a loudspeaker (I don't need to take the room into account), but is not either a generic HTRF-function tweaked headphone that tries to sound neutral to all ears (and probably fails on quite a few accounts).

"You want something that measures flat. But virtually all headphone designs take head-related transfer functions (HRTF) into account and try to equalize the sound in some way."

Indeed they do. I agree.

I understand that headphones ARE a special case (especially as they form a semi-close or close cup around the ears and as such can cause a lot of distortion themselves).

However, often this tweaking of the headphones sound is taken so far as to neutralize the effects on the pinna and even inside the ear canal, which to me would make the headphone useless for my purposes.

It may sound neutral to some heads and ears, but very hard for me to use, unless I knew what were the HTRF functions and tweaks used.

"But since audiologists aren't too concerned about hearing loss above 15kHz, audiometric headphones will not give you the treble extension you're looking for, up to 30 or 40 kHz."

Yes, I've just learned this. Thanks

---

JaZZ: "I'm still not quite sure what you want. There is no headphone frequency response independent of the ear and its necessarily individual shape/non-linearities."

Indeed there is not. This is also what I would like to do some testing about.

However, if the headphones I use ALREADY takes into account some statistically derived generic HTRF function (and does additional tweaking on top of that), for which I have know mathematical model...

Then how can I test for the non-linear effects of the head/ear combination if I don't even know how much the headphone already tweaks my input signal, in order to try and avoid some of the non-linearities of head/ear combo?

"Any measurements through an artificial ear (weighted, if need be) come closer to the hearing impression than without it – whatever the measurement conditions thereby may be. "

I wouldn't want to disagree with that. At least not yet, if ever

I know what I'm asking may be impossible, even stupid to some, but it's very hard to quantify that notion scientifically, if I can't test it. Based on preliminary literature research this has not been properly tested yet.

"What's the exact purpose of this? You had ultrasound on your wish list, but then you're considering yourself some «audiometric» headphones which barely reach 12 kHz... "

Well, my knowledge in audiometric headphones is (was) even less stellar than my knowledge in headphones in general. Thanks for bringing me up to speed

But what I would like to test for is in particular the non-linear functions of head / outer ear (especially) with as neutral sound source (that is not a loudspeaker) as possible.

"well as extension. Why should now a HP 1000 go for an ideal audiometric sound source and not any Stax for the same price? "

Because STax cause 2x the price the best dynamic headpones I can get WHERE I live (of course I can always go through the import hassle, but after shipping charges, insurance, 2-5% custom fee and 22% of value added tax added - ALL CUMULATIVELY on top of each... well I'm back to normal Stax range).

Maybe the cheapest stax could do it price and performancewise, I'm not sure. I can't seem to find reliable and comforting measurement data for them, however.

Also, correct me if I'm wrong, but I lived under the impression that most Stax phones for which accurate measurement data exists produce: very irregular frequency response, very sharply declining high frequencies and even some kind of intermodulation distortion from the connection frame?


I've only seen HE60 been supported and considered highly by audiometric/psychoacoustic researchers and that headphone is way out of my price range.

Please understand that what I write above is a serious intention to learn more about my choices and I mean no harm.

I appreciate all comments so far and would like to hear more, if somebody has any ideas.

English is my not my native tongue, so if somebody feels like I'm offending them, rest assured that it is not my intention. Eloquent expressions just don't come naturally to me - at least not in English that is

Regards,
Halcyon

 

[shivohum]

Halcyon, you might considering also asking your question on the Audio Asylum, where several audio designers and researchers hang around.

 

[Hirsch]

It occurs to me that a good person to ask would be Jan Meier. His website is www.meier-audio.com He carries a number of lines that might meet your needs, and would probably be able to make very good recommendations.

 

[JaZZ]

Thanks, halycon, for the clarification! Now I understand your intentions and your goal. But I guess you won't succeed with headphones. The interaction (interferences) of their housings, baffles and membranes with the outer ear inevitably makes them non-linear, but without any interaction (as a result of sufficient distance) there will be no bass. Apart from the fact that such headphones don't exist, if I'm not completely wrong. The closest to such a system that's crossing my mind are the AKG K 1000 (very expensive!) and the Switzerland manufactured Ergo models, the top one driven by a Heil Air Motion Transformer (also very expensive, but not so the lower models). Both Ergo models I have auditioned sounded very neutral and extended to my ears, and I suppose the baffle-ear interaction be substantially minor than with common headphones, though still existing.

Just an idea. But I think they can't adequately replace speakers for your purpose.

Btw: HP-1000s cost about 600-900 $...

JaZZ

 

[The Quality Guru]

Quote:

Btw: HP-1000s cost about 600-900 $...

They can cost that much, however, many times the cost is more like $400-$600, I would say. By most people's accounts, they are more than worth that price. Also in regards to John Grado/George Alessandro MSP vs. Joseph Grado HP-1000, in terms of neutrality a few who have heard both consider the HP-1000 to be more neutral. Manyactually do believe the HP-1000 to be the most neutral headphone available.

 

[kerelybonto]

halycon, have you considered buying an electrostatic system at an auction site, such as eBay? Good prices there to start with, but it's also easy to avoid import taxes and customs fees that way. Certain importers, such as AudioCubes, will invoice separately to avoid taxes and fees as well.

You may want to email HeadRoom and ask to see their non-normalized frequency response curves. It's hard to measure headphones' frequency response, but they've probably done it as well as anyone. If they have the info available in a useable format, I'd think they'd let you see it.

It's also probably worth looking up others who have done things similar to what you're trying to do and ask what equipment they used.

kerely