Well, you've got me going now ... had a look over at HeadRoom: Headphones: Full-Size, In-Ear, Wireless, Noise Cancelling, Headsets at what they show, AKG 272HD vs. HD800 - same methodology in testing always gives one a head start (is there a pun there?) ! Everything there points to the Sennheiser being superior: flatness of FR, distortion, square wave handling, impedance load is an absolute doddle ... so what's going on?
The clue is the FR: the AKG's fall off a cliff at about 2kHz ... all the nasty high frequency stuff is nicely pushed into the background - apart from the massive 15dB spike at 10kHz, I wonder how a speaker with that sort of performance would go down ...
Frank
The clue is the FR: the AKG's fall off a cliff at about 2kHz ... all the nasty high frequency stuff is nicely pushed into the background - apart from the massive 15dB spike at 10kHz, I wonder how a speaker with that sort of performance would go down ...
Frank
Auto-EQ the headphone -
One can take a low distortion headphone and using a probe microphone (which you can easily make that is flat) and an auto-EQ product, like used in recievers and stand-alone products by Audyssey and get this freq response:
Its a Monster/Beats product but any headphone will be flattened, automatically. The era of flat headphone FR is upon us! We can all have a flat FR... pick the headphone with lowest thd/IM and then flatten it for incredible sound!!! The flatter headphone you start out with the easier and lowest distortion results you will get.
And, it is fast to do so anyone's ear shape and size will be auto-EQ'ed for them.
Its all Done. Next problem, please.
Thx- RNMarsh
One can take a low distortion headphone and using a probe microphone (which you can easily make that is flat) and an auto-EQ product, like used in recievers and stand-alone products by Audyssey and get this freq response:
Its a Monster/Beats product but any headphone will be flattened, automatically. The era of flat headphone FR is upon us! We can all have a flat FR... pick the headphone with lowest thd/IM and then flatten it for incredible sound!!! The flatter headphone you start out with the easier and lowest distortion results you will get.
And, it is fast to do so anyone's ear shape and size will be auto-EQ'ed for them.
Its all Done. Next problem, please.
Thx- RNMarsh
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Thanks for that ... I was going to mention doing a little experiment: apply DSP to the recording being played through one headphone, say the HD800, to give it the same effective response as the AKG, to make everything fair, and then compare; also, do this in reverse, "hot" up the recording so the AKG replay matches the Sennheiser in response. I wonder what the reactions of listeners would be then ...
Frank
Auto EQ is cheap now and a stand-alone product could be easily made with dsp chip just for headphones. You dont need to do room averaging or anything like that. I found the volume in the ear/headphone cavity to be small enough to have constant pressure everywhere. So just slipping the probe under/between the headphone cushion and your head anywhere gives same results. Even a lame consumer could do it with a push of a button and a second later they being listening to the best sound he/she will ever have.
What are we waiting for? All the parts to do this exists and its easy now that I told you how and showed you the kind of results you can expect. This should (FR) become almost a non-issue with heaphones.
Thx-RNMarsh
What are we waiting for? All the parts to do this exists and its easy now that I told you how and showed you the kind of results you can expect. This should (FR) become almost a non-issue with heaphones.
Thx-RNMarsh
Oh, yes, and then all these rides to lunch in JB's Bentley...
We have a proverb here, that hits the nail verbatim:
Wes' Brot ich ess, des' Lied ich sing.
I'm unable to translate it without changing the meaning,
essentially it is that eating someone's bread makes one
his mercenary.
Bragging around that will not help one's credibility.
I'll leave it at this.
Gerhard
ok. I try it: I sing the battle song of those who's bread I eat.
Richard,
The automatic equalization of these headphones for frequency response will be a great thing as long as the price is low enough. What this doesn't do anything about is the actual sound of the membrane used in the headphone and the decay rate of the diaphragm. Just correcting the frequency response alone will not a great headphone make. The difference between a Mylar diaphragm and perhaps a metallic diaphragm or anything else would have to be looked at. I would be just as interested in the waterfall plots of decay time for these headphones as I would the simple frequency response curves. Anyone else have anything to say about the sound of any of these headphones after eq correction?
The automatic equalization of these headphones for frequency response will be a great thing as long as the price is low enough. What this doesn't do anything about is the actual sound of the membrane used in the headphone and the decay rate of the diaphragm. Just correcting the frequency response alone will not a great headphone make. The difference between a Mylar diaphragm and perhaps a metallic diaphragm or anything else would have to be looked at. I would be just as interested in the waterfall plots of decay time for these headphones as I would the simple frequency response curves. Anyone else have anything to say about the sound of any of these headphones after eq correction?
Please do not post embedded pictures (gizmodo, etc.) from other websites, link to them instead. Post deleted.
Ok, just heard back from my friend whose first job when he was contracted was to "...fix the Beats by Dre headphone design so they actually worked and were shippable."
He confirms that Iovine and Dre "never had a thing to do with the engineering of the headphones."
Lots of other juicy stuff, but that's all I have permission to divulge right now.
se
He confirms that Iovine and Dre "never had a thing to do with the engineering of the headphones."
Lots of other juicy stuff, but that's all I have permission to divulge right now.
se
The problem with headphone FR is we are in the waves lengths in medium/treble between the tranducer and the mike. So, with the stationnary waves, a flat curve will surely not be linear to our ears. I believe our ears will not produce the same resonances.
Looking at various headphones on this site we can see different devices had near the same resonances. I believe it depend more or less from the distance between the transducer and the mike too, because there is no reason different membranes resonates the same ?
Learning Center - Build a Headphone Graph | HeadRoom Audio
We can makes us an idea of an average ideal response curve witch will sound flat to our ears/brains ? Then we should apply an invert of this curve to correct our measurements, in order to can read a flat curve for a neutral headphone.?
Looking at various headphones on this site we can see different devices had near the same resonances. I believe it depend more or less from the distance between the transducer and the mike too, because there is no reason different membranes resonates the same ?
Learning Center - Build a Headphone Graph | HeadRoom Audio
We can makes us an idea of an average ideal response curve witch will sound flat to our ears/brains ? Then we should apply an invert of this curve to correct our measurements, in order to can read a flat curve for a neutral headphone.?
We all know this, dont we? You need to get the freq response right FIRST and foremost. Then the others --- a matter of priorities. The deviations are huge! get it taken care of and then focus on the rest. Like I said... pick the ones with the lowest distortion to do an auto-EQ with and you will be amazed. I use 3 headphones to play with -- the HiFiman HE500; The Sennheiser HD800, the AKG 702 and a Panasonic and an electrostatic. I have done what i showed and it makes a big difference and improvement - both. Do it and THEN move on to fixing all the other secondary issues. Trust me on this. It works and can be cheaply done in dsp chip.
If you want to experiment with auto EQ, buy a used reciever and use the auto-EQ that is built-in as described via headphone jack. Maybe even a DIY of taking out that auto-EQ and put it in a seperate box with upscale opamps et al.
I can see a headphone company doing this sort of thing or a high-end small company getting it going.
-RNMarsh
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This type of work has been explored extensively over the decades and artifitial ears produced that mimic very closely the ear. Its been thoroughly developed. My 'before' is very close to the results done via dummy head/ears when compared. i believe mine results are more accurate as it used a real ear and can be as accurate with each individual persons ear size/shhape/volume.
This has all been considered and done before this moment in time. i am giving you the short story version... something all can try for them selves. BTW - this is covered in Linear Audio mag along with my headphone amp saga.
Note: the headphone companies try to eq their models to have particular curves... some free field compensated and the like. The Sennheiser is Flat based upon certain principles within a narrow dB tolerance. Others may not be. Try it with your headphones and see if the sound isnt better flat at your ear's entrance.
Thx - RNMarsh
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Can-you describe this 'dummy head+ears' ? Molding of a real ear in silicon ? Then record of a flat loudspeaker in open ear to calibrate ?
(Excuse-me, Richard, i have no experience in headphone design, neither had read a lot about.)
Your questions are good but too lengthy for reply here. See Sennheiser's web site about the calibration of each of thier HD800. See how they do it.
You can also look up dummy heads for headphone testing. The makers have extensive R&D on it.
Demian Martin has one for headphone testing and has tested a number of headphones with it.
-RNM
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Thank you Richard,
The last nice set of headphones I remember hearing were electrostatic headphones from Sennheiser if I remember correctly. I'll have to get a copy of the Linear Audio article and read what you have done and created. It is an interesting field as it is so much different working with the closed air chamber of a headphone compared to a typical loudspeaker. I would never expect to achieve the same audio conditions of only hearing through the ears and not the entire body sensations and left right ear discrimination as with speakers but there are times when you don't want to disturb everyone else, so headphones definitely have their place in our systems.
The last nice set of headphones I remember hearing were electrostatic headphones from Sennheiser if I remember correctly. I'll have to get a copy of the Linear Audio article and read what you have done and created. It is an interesting field as it is so much different working with the closed air chamber of a headphone compared to a typical loudspeaker. I would never expect to achieve the same audio conditions of only hearing through the ears and not the entire body sensations and left right ear discrimination as with speakers but there are times when you don't want to disturb everyone else, so headphones definitely have their place in our systems.
The pressure in the small volume is equal everywhere. The distance between ear canal opening and the diaphram is a fraction of an inch... any such affects are at very highest freq only. Sometimes above the BW of the drivers. I moved the probe all around inside the area and didnt get different response curves. That was the very first issue I wanted to know also. If it varied then averaging would be needed like in rooms. it isnt there with the short distance and volume we have with headphones.
-Richard
This is a real condition which causes problems when recording... using headphones vs using speakers to monitor with.
The physical sensation when missing causes you to add EQ in the bass to compensate.... so it resembles speaker sound. Then when played over speakers, it sounds like too much bass. And, visa versa... Monitored with speakers leaves one feeling a loss of bass when listening with headphones. this is the basis of why some headphones have bass boost... some switchable.. on-off. Most recordings are recorded/eq'ed over speakers and when headphones are used to listen to them, they need some bass boost to 'sound' flat. Well know issue in recording field and one I learned and experimented with when i did live Bay Area recordings back in the day.
Thx-RNMarsh
Thank, Richard. I confirm i was never able to mix or equalize basses instruments with headphones. But it is helpfull to fine tune effects, reverberations, stereo image and room size, and verify little details you cannot always hear with monitors. Too, sometimes, it is difficult to separate some instruments in the monitors, and headphones help to listen to them more precisely.
About bass boost, i like The Porta Pro for that, while my Sennheizer (HD230, HD430) have too much of unnatural trebles. The 230 dual transducer is VERY disagreeable.
My AKG is a K240, with bass resonators, witch are just adding a lot of resonances and blurr.
About bass boost, i like The Porta Pro for that, while my Sennheizer (HD230, HD430) have too much of unnatural trebles. The 230 dual transducer is VERY disagreeable.
My AKG is a K240, with bass resonators, witch are just adding a lot of resonances and blurr.
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