[KeithPhantom]

Then I would guess that the fella who was EQing probably pushed the sub bass up into clipping. If he had just avoided boosting that last octave, it probably would have sounded pretty close.

Yes, but that also depends on the average level of the music, if the bass is down and the driver doesn't have that much distortion, it can handle some intensive EQ before it starts to creep up. We would have to know more specific to address his case.

 

[bigshot]

Sub bass is the range a lot of inexperienced people make errors when EQing. It isn't used in a lot of music, so if a person uses a song like that to EQ to, they can boost the non-existent sub bass along with the mid bass and not realize they're pushing it too high. Then they put on a hip hop song with tons of sub bass and it booms. Super common mistake. I've made it myself on occasion!

 

[Davesrose]

One thing I have enjoyed about planar headphones is a pretty good linear bass region. I don't listen to music genres that boost bass/sub-bass...but some that extend into lower registers. Examples being some alternative and electronic. Also have cathedral pipe organ music of Bach that really goes down (and sounds great with a good speaker system). Another factor with sub-bass is how much of that region is beyond auditory senses and more physical senses. I find I have quite a few more recent movies mixed in Atmos that take full use of LFE and boost sub-bass in a controlled manner to have some visceral impact when called for.

 

[bigshot]

Movies are where I have run into problems EQing sub bass in the past. At the end of Cabin in the Woods, there is a scene that has a continuous sub bass rumble that is close to the edge of audibility. The walls started rattling like crazy, even turning the overall volume level down didn't help. I had to do a little EQ tweak down low to fix it. It was one of those sounds you feel more than you hear.

 

[Davesrose]

Movies are where I have run into problems EQing sub bass in the past. At the end of Cabin in the Woods, there is a scene that has a continuous sub bass rumble that is close to the edge of audibility. The walls started rattling like crazy, even turning the overall volume level down didn't help. I had to do a little EQ tweak down low to fix it. It was one of those sounds you feel more than you hear.

Yeah, I also found that beginning of Blade Runner 2049 will really rattle the house when there's the begining scene of a close up of eye going to landscapes of protein farms and surrounds of an airborne car (you could hear the boom as well as feel it). Made for dramatic effects....makes me wonder how Denis Villeneuve's production will be for Dune. For most movies, I have the set subwoofer level I've set. Only on occasion do I find a track where it seems too powerful, and I have my remote app on my phone (where it's quick for me to lower the subwoofer level). I can also be this anal about picture quality as well...I find I can get to my picture profile to lower or raise brightness a few points just to maximize best black point on my OLED for that presentation!

 

[castleofargh]

The distortion of these is mainly high in the bass frequencies (20-50 Hz)


Everything over 1% is not optimal for small transducers such as headphones. Even though it isn't clearly audible for some, it can color the sound for me (-40 dB is pretty high for my liking).

About the sub, I'll get one right when I can get my first speaker system set up.

For clarity, when you see a spike at 50 or 60Hz(depending on the country) on graphs like those, assume it's bleeding signal from the power line. It usually is. I get spikes like that anytime I measure stuff with a quiet test signal(which usually alerts me that I messed up my calibration).
My THD measurements are almost always higher than those made with good rigs in a quiet environment, and I almost always have a lot of crap showing up in the sub range(part of that being noises from down in the valley that I can't avoid). Even then my result is for the most part, more generous than your graph. Which makes it suspicious in my eyes as I expect to always have among the most THD with my cheapo crap rigs(yeahhh! Number one in THD!!!!)^_^.

Taken with sweep reaching 90dB SPL @1kHz.


I'm not trying to argue that the HD650 doesn't distort audibly in the low end, it most likely does.
In term of personal impressions and preferences, I would not hesitate a second to throw away the HD650 for the low end of the LCD2. I can't say by ear what is frequency response, what is distortion, what is DD vs planar; so I can only guess why I feel the way I do, and THD has pretty poor correlation with impressions so that doesn't help much. But I did enjoy the sound of the LCD2 more. Too bad I can get comfy for hours with the 650 and couldn't with the LCD2 :'(

 

[KeithPhantom]

For clarity, when you see a spike at 50 or 60Hz(depending on the country) on graphs like those, assume it's bleeding signal from the power line. It usually is. I get spikes like that anytime I measure stuff with a quiet test signal(which usually alerts me that I messed up my calibration).
My THD measurements are almost always higher than those made with good rigs in a quiet environment, and I almost always have a lot of crap showing up in the sub range(part of that being noises from down in the valley that I can't avoid). Even then my result is for the most part, more generous than your graph. Which makes it suspicious in my eyes as I expect to always have among the most THD with my cheapo crap rigs(yeahhh! Number one in THD!!!!)^_^.

Taken with sweep reaching 90dB SPL @1kHz.


I'm not trying to argue that the HD650 doesn't distort audibly in the low end, it most likely does.
In term of personal impressions and preferences, I would not hesitate a second to throw away the HD650 for the low end of the LCD2. I can't say by ear what is frequency response, what is distortion, what is DD vs planar; so I can only guess why I feel the way I do, and THD has pretty poor correlation with impressions so that doesn't help much. But I did enjoy the sound of the LCD2 more. Too bad I can get comfy for hours with the 650 and couldn't with the LCD2 :'(

I know, I never considered the spikes, only the average sloping level of the signals.

 

[hakunamakaka]

Inexperienced people tend to EQ on the extremes on bass and treble. They don't realize that the sound they are wanting to change is an octave or two lower than the band they're adjusting. They end up doing a great big boost in a range their cans can't produce or their ears can't hear and it causes distortion. There as some headphones that can't do bass at all, but I'm quite sure the HD650 is able to be EQed to match your PM-3s pretty closely.

Inexperienced people tend to EQ on the extremes on bass and treble. They don't realize that the sound they are wanting to change is an octave or two lower than the band they're adjusting. They end up doing a great big boost in a range their cans can't produce or their ears can't hear and it causes distortion. There as some headphones that can't do bass at all, but I'm quite sure the HD650 is able to be EQed to match your PM-3s pretty closely.

Might be that the coll

Inexperienced people tend to EQ on the extremes on bass and treble. They don't realize that the sound they are wanting to change is an octave or two lower than the band they're adjusting. They end up doing a great big boost in a range their cans can't produce or their ears can't hear and it causes distortion. There as some headphones that can't do bass at all, but I'm quite sure the HD650 is able to be EQed to match your PM-3s pretty closely.

I’m not sure if hd650 can be EQed close pm3. When hd650 was EQed, it got bassier but just not the same bass, more into boomy and loose side, while my planars had that tightness and texture to it. On pm3 with bass heavy tracks I could feel that air pressure and with proper amping my headphone cups would even rattle without any distortion. There was something in mid range as well, especially in vocals that differed between those two HP. I’m not sure if all sound characteristics reflects in those frequency graphs, but the way I think it’s just different driver. Planar HP was the best audio buy for me so far...and raised SQ bar very high

 

[bigshot]

The last octaves on either end of the audible range are the least important. What I would recommend is to attenuate the sub bass to avoid clipping or distortion. Maybe do a roll off below 40. Sub bass is rarely very prevalent in headphones anyway, and it's the core frequencies that really give a set of cans its unique personality. I think you'll also find that there is considerable variation in response from one set of a particular make and model and another. High end cans aren't necessarily better quality, they just meet more exacting standards. The designer at Oppo told me that the PM-1s had a tolerance of +/-1dB, while the industry average is +/-3dB. He said that they rejected a lot of copies of the PM-1s that didn't meet spec. I suspect that those were recycled into the PM-2s and PM-3s. It's possible that the three models are just different degrees of deviation from the target curve.

Frequency response is the principle difference between different headphones. It's the level of the various frequencies of sound... that is exactly what you are hearing. Distortion is a deviation from accurate reproduction of the signal. That is much less prevalent in headphones than speakers, yet speakers can sound better than headphones. The only problem is at the top octave and the bottom octave where it is harder for headphones to produce controlled sound. But that doesn't matter as much because those frequencies aren't always in recorded music and they're at the edge of our ability to hear anyway. As long as they are kept out of clipping, that should be good enough. The bulk of bass response is above 40Hz, and the bulk of treble is below 10kHz.

 

[old tech]

I think this thread has totally deviated from the header topic.

 

[bigshot]

Then point us to a new test not mentioned in the original post and we’ll discuss it! Maybe this one... https://www.realhd-audio.com/?p=6993 Are there any details on the test anywhere?

 

[hakunamakaka]

The last octaves on either end of the audible range are the least important. What I would recommend is to attenuate the sub bass to avoid clipping or distortion. Maybe do a roll off below 40. Sub bass is rarely very prevalent in headphones anyway, and it's the core frequencies that really give a set of cans its unique personality. I think you'll also find that there is considerable variation in response from one set of a particular make and model and another. High end cans aren't necessarily better quality, they just meet more exacting standards. The designer at Oppo told me that the PM-1s had a tolerance of +/-1dB, while the industry average is +/-3dB. He said that they rejected a lot of copies of the PM-1s that didn't meet spec. I suspect that those were recycled into the PM-2s and PM-3s. It's possible that the three models are just different degrees of deviation from the target curve.

Frequency response is the principle difference between different headphones. It's the level of the various frequencies of sound... that is exactly what you are hearing. Distortion is a deviation from accurate reproduction of the signal. That is much less prevalent in headphones than speakers, yet speakers can sound better than headphones. The only problem is at the top octave and the bottom octave where it is harder for headphones to produce controlled sound. But that doesn't matter as much because those frequencies aren't always in recorded music and they're at the edge of our ability to hear anyway. As long as they are kept out of clipping, that should be good enough. The bulk of bass response is above 40Hz, and the bulk of treble is below 10kHz.

Oppo PM-1 has bigger driver than PM-3 and I believe is way better sounding HP. I’m wondering as well if these paid bit perfect players like audirvana make an audible SQ difference between itunes or streaming services

 

[bigshot]

I tried audirvana and didn't like it. The interface is really clunky. Or at least it was when I tried it. I doubt there is any difference in sound quality. My Macs are all audibly transparent. It doesn't get any better than that.

Maybe the PM-2s were the PM-1s that didn't meet spec.

 

[KeithPhantom]

Oppo PM-1 has bigger driver than PM-3 and I believe is way better sounding HP. I’m wondering as well if these paid bit perfect players like audirvana make an audible SQ difference between itunes or streaming services

Changes in sound quality by software are really minor (unless you are talking about lossy compression), if the software is well-designed, the differences between "bit-perfect" and processed audio (usually up/downsampling, but it can be also EQ or other DSP) are minor and inaudible.

 

[KeithPhantom]

The last octaves on either end of the audible range are the least important. What I would recommend is to attenuate the sub bass to avoid clipping or distortion. Maybe do a roll off below 40.

Many mixing engineers just high-pass everything in the bass ranges at even higher frequencies, so you're not even listening to the original content at those frequencies.