Can two headphones with the exact same frequency response sound completely different?

Not a stupid question at all, i have never seen 2 exactly the same , technically that is probably not possible.

Transient response is not visable in FR graph and could make two cans sound very different.

Quote:

Originally Posted by astroid 

Not a stupid question at all, i have never seen 2 exactly the same , technically that is probably not possible.

Transient response is not visable in FR graph and could make two cans sound very different.

While it's not directly visible you can extract the impulse/step response from the frequency response (which include phase response).

Also, I don't think transient response would be a problem but I agree that two cans could sound very differently, e.g. think of 0.1% vs. 10% THD/IMD.

Quote:

Originally Posted by xnor I don't think transient response would be a problem but I agree that two cans could sound very differently, e.g. think of 0.1% vs. 10% THD/IMD.

 

Right, transient response is the same as high frequency response. Another factor for sound quality is ringing due to mechanical and acoustical resonance.

--Ethan

If the two headphones have the same frequency response (magnitude and phase), and have zero nonlinearities at all (0% distortion, etc. and with some conditions met, they are pretty much textbook LTI), then from either the impulse response or frequency response, you have a perfect characterization of the behavior with any input.  If those things are identical then they will sound perfectly identical with any kind of input

In practice because of various nonlinearities: think mechanical and acoustical resonances as mentioned above, maybe the nature of the damping and motion of the driver (I'm not sure really), and so on, those conditions aren't met.  Thus the FR doesn't tell you everything.

Pretty much every potential behavior in the headphone, we could measure.  There just may be an infinite number of measurements needed to describe the headphones, unless I'm missing some simplification.

Also keep in mind that different people have different ears and the sound that actually gets to the eardrums may be somewhat different from person to person.  Additionally, there is some dependence on the positioning of the headphone on the head.

Hello forum,

I had the same question and did't find it appropriate to start a new thread.

I own a beyerdynamic dt 990 pro and a sennheiser hd 650, both driven by a xonar stx, which I consider uncolored and distortion free when driving cans inside its limits-of course. (Audio sceptic here. I don't believe in different sounding amps when design is correct and Zout sufficiently low.)

Although both cans have very good measurements hd 650 is much more accurate. For instance, when i listen to heavy metal the sound is much more aggressive on the 650(in the mids), as it should be. 990 pro(and other beyer products like dt 880 pro) have a tendency to mellow sounds even if they produce more high frequencies. Hd 650 can sound more harsh or vivid when it is required.

I tried equalizing in order to simulate hd 650's FR, but in vain. Mids were always sweeter and bass less dynamic and slow. Look at these measurements:

http://en.goldenears.net/index.php?mid=GR_Headphones&document_srl=10634

http://en.goldenears.net/index.php?mid=GR_Headphones&category=275&document_srl=11616

Both cans have good transient response, both have rapid decay and both have low thd(according to other sites) at normal listening levels. So, where does the difference come from?

That's just the thing, their frequency response graphs are extremely different. 

Quote:

Originally Posted by TMRaven 

That's just the thing, their frequency response graphs are extremely different. 

But I used eq to cut bass( mostly below 120Hz~150Hz) and treble significantly and still the mids were different(less vivid) at all volumes(volume can alter perceived vividness).

EDIT: Could it be that the 650 have a very brief overreaction(big overshoot) in the step response test. I 've heard that many systems try to mimic detail that way. I've noticed a similar behaviour in innerfidelity graphs regarding the same can.

In my experience EQ never is able to replicate the true native sound of different headphones.

it also depends on how the FR is measured.  the graphs that we see on innerfidelity and headroom, for example, are really graphs of the interaction between the headphones and measuring equipment.  since any given person's head is not going to be the same shape as the dummy head, the FR for that person will differ from what you see in the graphs.  doesn't mean information isn't useful.

it seems to me that even if you had microphones deep in your ear canals and measured two headphones to have identical responses there could still be perceived differences in the sound; a possibility that comes to mind is a larger driver emitting waves that have more interaction with the outer ear surface.  this is just speculation though.

Were you using a parametric eq? or just a graphic eq? And how were you determining the values of the cuts (usually you should use raw response data, not the hrtf compensated) ? 

My guess is you just didn't have it quite right. Also, the 990 are known for a big V eq, with recessed mids - it is possible that even correcting the V, you will still be left with lackluster mids. The 880 are the way to go for accuracy. 

I experimented with a 31-band graphic equalizer for foobar knowing that attenuation works for a certain range of frequencies around the central one. I was carefull not to "harm" the mids.

I tried various amounts of reduction for treble, bass and both.

I think that beyers are not so dynamic, so efficient. I don't know how to say.

 

Quote:

Originally Posted by TMRaven 

In my experience EQ never is able to replicate the true native sound of different headphones.

That's my point. As I noticed there is a relevant thread in the same section:http://www.head-fi.org/t/610161/why-some-headphones-are-more-revealing-than-others

There are headphones that can sound detailed/vivid without a lot of hf.

obobskivich writes:

Semiclosed headphones can suffer a little from resonances in the lower register and also damping varies from headphone to headphone.

@scud80

You are right, but the reference point is the same(equipment). Graphs always show relative differences between cans but these differences exist regardless of whether you're wearing or testing them. Although the range may vary among individuals for the reasons you mention.