How do we know if something is actually "neutral"?

[xnor]

Here's my answer to the OP:
 
I guess the most straightforward way is to have a preferably treated room with calibrated (to "neutral") speakers. Compare something as simple as pink noise playing through the speakers to your headphones at the same volume. Switch back and forth, the differences in frequency response should be quite obvious.
 
Why is this better than just looking at measurements? Well, the main reason is that the dummy heads used for the measurements are based on some average head/ear. If your head is a bit wider than the dummy head you'll probably get more bass, and so on..

 

[EthanWiner]

Thanks Doug.
 
Quote:

Originally Posted by Chris J /img/forum/go_quote.gif
e.g. is the mix for Bruce Springsteen's Magic as bad as the CD?
Does the Born To Run final mix actually sound as bad as the CD?

I don't own any Springsteen CDs so I can't comment on that. I can tell you that a friend once brought over a Springsteen concert DVD and the sound quality was atrocious. So learning that whoever mixes Springsteen's stuff is not very good wouldn't surprise me. But to be clear, when I said mix engineer and producer I should have also included mastering engineer. Again, the goal (for me) is to hear the artist's intent, for better or for worse. You can always add an EQ if you want to adjust the sound yourself on a per-recording basis.
 
--Ethan

 

[audiosampling]

Quote:

I mean we don't exactly have a reference to something that sounds neutral. Can we tell by looking at a measurement graph if a headphone is neutral? Is it difficult to make a headphone sound neutral? 

 
Although "neutrality" is a good thing to look after, it should be noted that our ears are not linear. We hear frequencies differently depending on their levels. For example, at higher levels, bass and highs are felt louder compared to lower levels (see loudness curve or the fletcher-munson curves). 
 
This means that you can be very satisfied with a non-neutral headphone, which boosts the bass and the highs. It will allow you to perceive the same impression as if you were playing music louder, but at reduced levels.This is a great ear-saver!
 
Instead of checking for neutrality, I'd check for the absence of frequency peaks, across the whole audible frequency range. You can find such a test signal here: http://www.audiocheck.net/testtones_sinesweep20-20k.php or generate your own here: http://www.wavtones.com/

 

[NimbleTurtle]

Quote:

 
Although "neutrality" is a good thing to look after, it should be noted that our ears are not linear. We hear frequency differently depending on their levels. For example, at higher levels, bass and highs are felt louder compared to lower levels (see loudness curve or the fletcher-munson curves). 
 
This means that you can be very satisfied with a non-neutral headphone, which boosts the bass and the highs. It will allow you to perceive the same impression as if you were playing music louder, but at reduced levels.This is a great ear-saver!
 
Instead of checking for neutrality, I'd check for the absence of any frequency peak, across the whole audible frequency range. You can find such a test signal here: http://www.audiocheck.net/testtones_sinesweep20-20k.php or generate your own here: http://www.wavtones.com/

That's a good point. Do you think that is the reason why some headphone companies intentionally make a V-shaped sound? 

 

[audiosampling]

Quote:

That's a good point. Do you think that is the reason why some headphone companies intentionally make a V-shaped sound? 

 
I don't know if they do it intentionally, but for sure, this is the reason why the V-shape sounds so pleasing. Definitely, there is good reason to offering V-shaped headphones (intentionally or not)... rather than the opposite. Imagine: with A-shaped headphones, you'd need to turn the level up to simulate what your ears would hear at lower levels! I don't think there is a profitable business for that

 

[tzjin]

Quote:

 
This means that you can be very satisfied with a non-neutral headphone, which boosts the bass and the highs. It will allow you to perceive the same impression as if you were playing music louder, but at reduced levels.This is a great ear-saver!

 
Sorry, that statement basically assumes the midrange does not exist and does not matter, which is untrue.

 

[AudioDwebe]

Quote:

Yes, that's me. The original version of my Cello Rondo video now has more than 1.5 million views around YouTube. Then last year I made a new version in high-def and put it using my own account:
 
http://www.youtube.com/watch?v=ve4cBOnSU9Q
 
--Ethan

Hey Ethan,
 
Pretty nice, man!  Enjoyed it tremendously.
 
Great that someone in the acoustical treatment world is also a real musician. 
 
Cheers.
 
Mamoru

 

[Chris J]

Quote:

Thanks Doug.
 
I don't own any Springsteen CDs so I can't comment on that. I can tell you that a friend once brought over a Springsteen concert DVD and the sound quality was atrocious. So learning that whoever mixes Springsteen's stuff is not very good wouldn't surprise me. But to be clear, when I said mix engineer and producer I should have also included mastering engineer. Again, the goal (for me) is to hear the artist's intent, for better or for worse. You can always add an EQ if you want to adjust the sound yourself on a per-recording basis.
 
--Ethan

 
Some of Springsteen's worst sounding stuff is also rather compressed and distorted. Sigh.....
 
Some of his finest sounding recordings are outstanding:  i.e. a few of the songs from "Tracks".

 

[Deathwish238]

Quote:

That's a good point. Do you think that is the reason why some headphone companies intentionally make a V-shaped sound? 

 
Two things:
Our ears do not hear linearly with volume. As you turn the volume up, their sensitivity to bass and treble go down to protect our ears.
Our ears to begin with do not hear things flatly. Bass is hardest to hear followed by treble.
 
So a V with more bass than treble should actually sound more 'neutral' than a perfectly flat frequency response. If you take a pair of headphones, look at their FR, and then apply an EQ that flattens the curve, you'll end up with a flat sound that's not enjoyable to listen to. Which is why when people do EQ, they use pink noise sweeps typically and rely on their ears, not the FR that has been actually measured.

 

[vid]

A curious pair of headphones that Tyll very recently measured - the Noontec Zoro (http://www.innerfidelity.com/images/NoontecZoro.pdf). He found them relatively balanced compared to some other ~$100 phones, if a bit muffled.
 
What's interesting about them in Tyll's measurements is the raw frequency response. It's essentially flat from 20 Hz to 3 kHz, no kidding. That's not how the raw response of any headphone should look - yet they apparently sounded acceptably balanced. With a flat raw response.

 

[TMRaven]

Quote:

 
What's interesting about them in Tyll's measurements is the raw frequency response. It's essentially flat from 20 Hz to 3 kHz, no kidding. That's not how the raw response of any headphone should look

 
 
Why not?

 

[vid]

Quote:

 
Why not?

 
Admittedly a good question in light of Tyll's finding a response like that balanced. Out of curiosity, do you know of another headphone whose raw graph (measured with an artificial ear) would be flat like that?

 

[TMRaven]

HE-400 and LCD-2 seem to be pretty flat to 2khz and as well as the treble, with the exception of large 3khz bumps.  HE-400 measures relatively flat on the raw graph and sounds relatively neutral to my ears as well.  I know the plastic ear isn't the best representation of what the human ear does to sound, but I'd imagine it would be closer to what a headphone actually sounds like to us rather than the compensated graph.

 

[vid]

As you say, the LCD-2, though kinda flat, has a clear 3 kHz peak typical of a raw response (and caused by an ear canal resonance). The HE-400 raw response is kinda weird, but as you say, a 3 kHz peak is to be found there as well, albeit obscurely. The Zoro on the other hand looks like they were accidentally equalized to be flat at the eardrum rather than at the level of perception - there's no 3 kHz peak at all, not even a little, to indicate any kind of conventional equalization.
 
(If the raw response is closer to what you hear than the compensated graph, chances are there's something wrong with the compensation curve that was used...)

 

[TMRaven]

The difference between flat at the eardrum vs perception?  
Raw response closer to what a person hears compared to a compensated graph, then something's wrong with the compensated graph?
 
 
I'm not quite sure at what you're getting at.  The raw graph should be closer to what your average ear hears, while the compensated graph is compensated to simulate the headphones' sound in free space, only for comparison purposes.