[DairyProduce]

  funny how people are already jumping to conclusions

+1

 

[musicheaven]

 
Not a whole lot, but that is dodging the point that 10KHz rolloff is unacceptable, especially for a $1099 flagship headphone. Those frequencies are important for adding realism to the recording.
The Oppo PM-1 may not actually sound like that though, we'll have to wait for subjective reviews for more consensus.

I would be nice to have a headphone pair that could truly scan the full audible range (20 - 20Khz) in a flat fashion but the truth of the matter is, the material being used in the headphone transducer and how flexible it becomes under high frequencies prevent that to happen, you have to imagine a semi flexible membrane vibrating at the frequency producing sound pressure that creates the equivalent of a 10,000 vibrations per second sound, that is real fast and most likely traveling at a very short displacement distance, not like a lower frequency sound having a wider vibrating range. The issue that most headphone manufacturers are facing is too large of a transducer creates distortion at high frequencies. What we mostly hear from the lush cymbals sound which degenerates quite nicely are actually the harmonics and overtones giving it a rich complex treble sound. It's a compromise between using commonly available material and pushing the headphones towards distortion.

 

[jerg]

  I would be nice to have a headphone pair that could truly scan the full audible range (20 - 20Khz) in a flat fashion but the truth of the matter is, the material being used in the headphone transducer and how flexible it becomes under high frequencies prevent that to happen, you have to imagine a semi flexible membrane vibrating at the frequency producing sound pressure that creates the equivalent of a 10,000 vibrations per second sound, that is real fast and most likely traveling at a very short displacement distance, not like a lower frequency sound having a wider vibrating range. The issue that most headphone manufacturers are facing is too large of a transducer creates distortion at high frequencies. What we mostly hear from the lush cymbals sound which degenerates quite nicely are actually the harmonics and overtones giving it a rich complex treble sound. It's a compromise between using commonly available material and pushing the headphones towards distortion.

But we are talking about ultra-thin tensioned mylar membranes, not thick(er) rigid domed diaphragms.

 

[x RELIC x]

I'm no expert in reading frequency graphs but it looks like the roll off happens after 15kHz, compared to the other flagship headphones. Again, it looks pretty low for the 17-18kHz region, next to the other two, but that's pretty high in the frequency range. Frequency response graphs are not linear in the x axis. Note how much space is dedicated on the graph for the 1-2kHz and then less for the 2-5kHz region. Then it starts compressing more from 5-10kHz and finally 10-20kHz the graph gets very compressed.

That's what I see anyway. Looks awesome to me for way less money than the others.

 

[conquerator2]

There are headphones that extend up to 15khz. There might be slight a slight decline there but it is possible without distortion.
The problem is that the roll-off is very steep and fast in case of the Oppo.
Again, those who like Audeze will probably find this headphone really good.
It's not all black and white. People like different things and have different ears.

 

[x RELIC x]

I'm no expert in reading frequency graphs but it looks like the roll off happens after 15kHz, compared to the other flagship headphones. Again, it looks pretty low for the 17-18kHz region, next to the other two, but that's pretty high in the frequency range. Frequency response graphs are not linear in the x axis. Note how much space is dedicated on the graph for the 1-2kHz and then less for the 2-5kHz region. Then it starts compressing more from 5-10kHz and finally 10-20kHz the graph gets very compressed.

That's what I see anyway. Looks awesome to me for way less money than the others.


Here is the graph comparing PM-1 (blue) with the LCD-X and the HE-6 from about.stereos

 

[KamijoIsMyHero]

The graph is logarithmic ..

 

[jerg]

I'm no expert in reading frequency graphs but it looks like the roll off happens after 15kHz, compared to the other flagship headphones. Again, it looks pretty low for the 17-18kHz region, next to the other two, but that's pretty high in the frequency range. Frequency response graphs are not linear in the x axis. Note how much space is dedicated on the graph for the 1-2kHz and then less for the 2-5kHz region. Then it starts compressing more from 5-10kHz and finally 10-20kHz the graph gets very compressed.

That's what I see anyway. Looks awesome to me for way less money than the others.


Here is the graph comparing PM-1 (blue) with the LCD-X and the HE-6 from about.stereos

 
 

The graph is logarithmic ..

 
^This. 

 

[musicheaven]

I'm no expert in reading frequency graphs but it looks like the roll off happens after 15kHz, compared to the other flagship headphones. Again, it looks pretty low for the 17-18kHz region, next to the other two, but that's pretty high in the frequency range. Frequency response graphs are not linear in the x axis. Note how much space is dedicated on the graph for the 1-2kHz and then less for the 2-5kHz region. Then it starts compressing more from 5-10kHz and finally 10-20kHz the graph gets very compressed.

That's what I see anyway. Looks awesome to me for way less money than the others.


Here is the graph comparing PM-1 (blue) with the LCD-X and the HE-6 from about.stereos

 
It's starting at around 10khz, a little dip for a few khzs then a bump close to 15khz to finish down the curve. It's not a true pass band filter but the PM-1 is really getting close to it with the least bass line clip.
 
Here is the HD800 which has a reputation of having a 0-50khz range. A major dip at 10khz and then trying to get back but still staying underneath the 0 db line for the balance. The bump at around 8khz is apparently to give it a speaker sound response (most of them do).
 

 

[jerg]

   
It's starting at around 10khz, a little dip for a few khzs then a bump close to 15khz to finish down the curve. It's not a true pass band filter but the PM-1 is really getting close to it with the least bass line clip.
 
Here is the HD800 which has a reputation of having a 0-50khz range. A major dip at 10khz and then trying to get back but still staying underneath the 0 db line for the balance. The bump at around 8khz is apparently to give it a speaker sound response (most of them do).
 

Headroom measurement has a different methodology than the source for the PM1, as such they are utterly and completely non-comparable. Heck even if the methods are identical (which they aren't in this case) environmental and personal differences in setting things up will still account for wild differences. 
 
This is a very crucial rule for analyzing any measurement, is that you simply don't cross plots from different sources.

 

[aamefford]

Or better yet, objective review. People other than the testers, those who bought the headphone for their money.
No offense meant.

None taken from me. That's why I tried to be very clear that I'm predisposed to like them.

 

[musicheaven]

  Headroom measurement has a different methodology than the source for the PM1, as such they are utterly and completely non-comparable. Heck even if the methods are identical (which they aren't in this case) environmental and personal differences in setting things up will still account for wild differences. 
 
This is a very crucial rule for analyzing any measurement, is that you simply don't cross plots from different sources.

 
Be my guess if you can find better measurements and graphs by all means attach them to your response. As far as what I saw, it's an approximation and it does not change the results, they all clip at a specific frequency values and there is no measurements that is going to change that.

 

[jerg]

   
Be my guess if you can find better measurements and graphs by all means attach them to your response. As far as what I saw, it's an approximation and it does not change the results, they all clip at a specific frequency values and there is no measurements that is going to change that.

The only way I can see to extrapolate how HD800 compares to PM1 in terms of treble behaviour, and only roughly, is to use HD800 + LCDX + HE6 in the same headroom plot. Then cross the LCDX and HE6 plots between the headroom and the about.com measurements, and predict how PM1 would look with the headroom compensation.
 
So...here's the un-smoothed tri-fecta FR plot (I like un-smoothed because it doesn't hide anything strange):
 

 
Here's that same plot but with HD800 removed:
 

 
And here's the About.com measurement again, of LCDX, HE6, and PM1:
 

 
I'm not gonna do any extrapolation, anyone interested is welcome to though.

 

[jerg]

Funny how the HE560 thread was obssessed with sub-bass behaviour last week, and now PM1 thread is obssessed with supra-treble behaviour.

 

[zilch0md]

Or better yet, objective review. People other than the testers, those who bought the headphone for their money.
No offense meant.

 
No offense taken.  

 
 
But consider the bias that can lead to defending a purchase.  A reviewer who has neither spent any of his own money nor been gifted with a product, is perhaps the least biased.