Perception and Measurement of Headphone Sound Quality Options

[Speedskater]

Sean Olive has a new blog page.

"The Relationship between Perception and Measurement of Headphone Sound Quality"

http://seanolive.blogspot.com/2013/04/the-...eption-and.html

[benski]

The headphones aren't specifically identified in the findings, for obvious reasons.

Judging by the frequency response graphs, and comparing them to the graphs on headphone.com, here is my best guess

hp1 - Audeze
hp2 - V-MODA
hp3 - k550
hp4 - k701
hp5 - bose QC15
hp6 - beats

Feel free to correct me if I'm wrong!

This post has been edited by benski: Apr 24 2013, 21:26

[dhromed]

marketing B.S. (Before Science)

he he he he

[chicks]

The headphones aren't specifically identified in the findings, for obvious reasons.

He links to S&V mag, http://www.soundandvisionmag.com/blog/2012...udio-story-2012 who give it their best guess.

[benski]

The headphones aren't specifically identified in the findings, for obvious reasons.

He links to S&V mag, http://www.soundandvisionmag.com/blog/2012...udio-story-2012 who give it their best guess.

From the article - " it looks to me like the clearly preferred headphone was the Audeze LCD2, followed by the AKG K701 and (surprise!) the Bose QC-15"

There's no way that the Bose QC15 aren't HP5. Look at the characteristic "bump" around 30Hz, and the steep rise up to it.



and compare to



HP5 is the only response graph with that same bump.

This post has been edited by benski: Apr 24 2013, 22:25

[extrabigmehdi]

It's obvious that the HP1 is the audeze, because of the statement : "Most preferred headphone in sound
quality is the least preferred in comfort".
It is well known that the audeze is heavy, and somehow the "blind test" is flawed.

[solive]

The headphones aren't specifically identified in the findings, for obvious reasons.

Judging by the frequency response graphs, and comparing them to the graphs on headphone.com, here is my best guess

hp1 - Audeze
hp2 - V-MODA
hp3 - k550
hp4 - k701
hp5 - bose QC15
hp6 - beats

Feel free to correct me if I'm wrong!

You're wrong on 5 out of 6 Send checks made out to me for the right answers

[solive]

It's obvious that the HP1 is the audeze, because of the statement : "Most preferred headphone in sound
quality is the least preferred in comfort".
It is well known that the audeze is heavy, and somehow the "blind test" is flawed.

We admitted up front that comfort/tactile factors were not eliminated from the test, and in that sense the test wasn't blind. However, our listeners didn't know which brands and models headphones were being tested so unless they could recognize the specific brand/model by its weight/comfort alone, their judgments weren't influenced by brand, price,etc

We thought about anesthetizing subjects from the neck up to eliminate these tactile/weight factors but our lawyers wouldn't go for it

This post has been edited by solive: Apr 25 2013, 01:40

[IgorC]

Interesting article. It will be even better with some classic Sennheiser pairs.
I'll be happy with any of those headphones, except beats.

[godrick]

I wonder which of the following is correct:

hp1 - k550
hp2 - k701
hp3 - Audeze
hp4 - V-Moda
hp5 - bose QC15
hp6 - beats

An interesting test. From what little I understand, the B&K house curve derived in 1974 still reflects the preferred loudspeaker room frequency response. Dr. Olive or others, any thoughts on trying to test headphones equalized or not to the B&K house curve, or using a methodology similar to B&K to derive a preferred frequency response for headphones?

[extrabigmehdi]

Here is my guess, based on user comments only.

hp1: audeze lc2. ( worst for comfort, excellent bass extension)
hp2: k701 (thin bass, bright, wide soundstage)
hp3: vmoda crossfade (comfy, good spectral balance)
hp4: k550 (best soundstage for the remaining closed cans, good spectral balance).
hp5:bose qc15 (comfy, bad spectral balance).
hp6: beats studio ( colored, boomy, worst spectral balance)

edit: swapped vmoda & bose , as expect the vmoda to have a better spectra balance.

The study doesn't consider other measurements beside freq response such like: impulse response, square wave response, thd+ noise .....

This post has been edited by extrabigmehdi: Apr 25 2013, 03:30

[dhromed]

In practical terms, i.e. when buying some phones for actual money; can we safely conclude that frequency graphs like the ones on Headroom are adequate indicators of sound quality?

[extrabigmehdi]

In practical terms, i.e. when buying some phones for actual money; can we safely conclude that frequency graphs like the ones on Headroom are adequate indicators of sound quality?

A "neutral" frequency response, is the first thing that people ask when looking for a headphone.
But it's not enough to warrant good sound quality.
In other hand, you'd see people rejecting some headphones models , just by looking at the frequency responses.
It's the case of the expensive denon d7100, there's an important bass emphasis, if you look at he graph.

[zheka]

Dr. Olive dropped a few hints about identity of the headphones here and in the comments over at his blog.

According to him, the following list contains only one correct entry:

hp1 - Audeze
hp2 - V-MODA
hp3 - k550
hp4 - k701
hp5 - bose QC15
hp6 - beats


This one has three correct entries :

HP1 - LCD-2 (Audeze)
HP2 - K701
HP3 - Crossfade (v-moda)
HP4 - K550
HP5 - Bose
HP6 - Beats

There are three entries in both lists that match:
HP1, HP5 and HP6

I am confident that the correct one is HP1(Audeze). This makes the H5 and H6 in the second list wrong, taking 2 out of three "wrong" spots.
Out of the remaining 3 - two must be right and one must be wrong:

HP2 - K701
HP3 - Crossfade (v-moda)
HP4 - K550

we also know that none of the remaining three can swap places because it would make 2 "wrongs" which cannot happen. The Bose or the Beats must be swapped with one the three.

with this in mind, my list is as follows

HP1 - LCD-2 (Audeze)
HP2 - K701
HP3 - Bose
HP4 - K550
HP5 - Beats
HP6 - Crossfade (v-moda)

EDIT: the first three match the S&V guess. They did not assign the last three. Note that the S&V guys use the same measuring gear (G.R.A.S. 43AG ear simulator) that was used for the study.


This post has been edited by zheka: Apr 25 2013, 17:21

[chicks]

You're wrong on 5 out of 6 Send checks made out to me for the right answers

So, Dr. Olive, which headphones do you use?

[xnor]

I've seen him wearing K550's about a year ago in a podcast.

This post has been edited by xnor: Apr 25 2013, 18:11

[markanini]

In practical terms, i.e. when buying some phones for actual money; can we safely conclude that frequency graphs like the ones on Headroom are adequate indicators of sound quality?

Shure SRH440 & Grado SR60



Denon AH-D7000



All made using professional head and torso simulator equipment costing thousands of dollar, yet the graphs differ. There's simply no consensus on measurement and calibration standards at the moment.

EDIT:Images fixed

This post has been edited by markanini: Apr 25 2013, 19:01

[DVDdoug]

In practical terms, i.e. when buying some phones for actual money; can we safely conclude that frequency graphs like the ones on Headroom are adequate indicators of sound quality?

Yes, unless there is audible distortion.

Ethan Winer identifies four things that affect/describe sound-reproduction quality:
Noise
Distortion
Frequency Response
Time Based Errors

Headphones don't generate any noise (other than mechanical noise when you move the cord, etc.), and they don't generate time-based errors either. Distortion & frequency response are the only things left.

[xnor]

All made using professional head and torso simulator equipment costing thousands of dollar, yet the graphs differ. There's simply no consensus on measurement and calibration standards at the moment.

Your links are broken and I disagree. Look at the raw data. Differences at the very low end are due to seal problems (see different raw curves at innerfidelity), difference at high frequencies are due to placement.

[solive]

Dr. Olive dropped a few hints about identity of the headphones here and in the comments over at his blog.

According to him, the following list contains only one correct entry:

hp1 - Audeze
hp2 - V-MODA
hp3 - k550
hp4 - k701
hp5 - bose QC15
hp6 - beats


This one has three correct entries :

HP1 - LCD-2 (Audeze)
HP2 - K701
HP3 - Crossfade (v-moda)
HP4 - K550
HP5 - Bose
HP6 - Beats

There are three entries in both lists that match:
HP1, HP5 and HP6

I am confident that the correct one is HP1(Audeze). This makes the H5 and H6 in the second list wrong, taking 2 out of three "wrong" spots.
Out of the remaining 3 - two must be right and one must be wrong:

HP2 - K701
HP3 - Crossfade (v-moda)
HP4 - K550

we also know that none of the remaining three can swap places because it would make 2 "wrongs" which cannot happen. The Bose or the Beats must be swapped with one the three.

with this in mind, my list is as follows

HP1 - LCD-2 (Audeze)
HP2 - K701
HP3 - Bose
HP4 - K550
HP5 - Beats
HP6 - Crossfade (v-moda)

EDIT: the first three match the S&V guess. They did not assign the last three. Note that the S&V guys use the same measuring gear (G.R.A.S. 43AG ear simulator) that was used for the study.

You gentlemen are too clever for me !!

[markanini]

Your links are broken and I disagree. Look at the raw data. Differences at the very low end are due to seal problems (see different raw curves at innerfidelity), difference at high frequencies are due to placement.

If you'll look at the graphs you'll see its more than just the low and highs.

This post has been edited by markanini: Apr 25 2013, 19:26

[solive]

You're wrong on 5 out of 6 Send checks made out to me for the right answers

So, Dr. Olive, which headphones do you use?

I don't actually wear headphones very often except when traveling on a plane or doing listener training.

For planes I used in-ear headphones. I used to be a fan of Etymotic ER4's, but I find them to be too thin in the bass.

I recently received a pair of AKG K3003's as part of an award I received from my employer.

I honestly haven't found an ideal headphone yet. I think there is room for improvement.

[solive]

In practical terms, i.e. when buying some phones for actual money; can we safely conclude that frequency graphs like the ones on Headroom are adequate indicators of sound quality?

Yes, unless there is audible distortion.

Ethan Winer identifies four things that affect/describe sound-reproduction quality:
Noise
Distortion
Frequency Response
Time Based Errors

Headphones don't generate any noise (other than mechanical noise when you move the cord, etc.), and they don't generate time-based errors either. Distortion & frequency response are the only things left.

Actually some of the ANC (active noise cancellation) units do produce noise. It's actually a nuisance variable when doing blind tests: if there's no music to mask it people will identify it by the noise.

This post has been edited by solive: Apr 25 2013, 19:40

[extrabigmehdi]

Headphones don't generate any noise (other than mechanical noise when you move the cord, etc.), and they don't generate time-based errors either. Distortion & frequency response are the only things left.

What a statement.
The website innerfidelity provide different measurements for each headphones related to sound : frequency response, thd+ noise, impulse response, 30hz square wave response, 300 hz square wave response. So basically you are saying that I only need to look at the graph for freq response & THD + noise to get an idea of sound quality ?
http://www.innerfidelity.com/headphone-data-sheet-downloads
And by the way, I don't know how the graph "Electrical Impedance and Phase" depending of frequency, can be interpreted in a useful way.

[pdq]

And by the way, I don't know how the graph "Electrical Impedance and Phase" depending of frequency, can be interpreted in a useful way.

This could be useful in explaining the interactions between the headphone and the amplifier, if the amplifier has non-zero output impedance.