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Oppo PM-1 Planar Magnetic Headphone Impressions Thread - Page 18

post #256 of 2918
Quote:
Originally Posted by m2man View Post

Some of the Beats models have a pretty decent FR curve. It's helpful that the FR on the PM-1 is flat but it tells us nothing useful at the same time. Speed, decay, sound stage, prat, distortion, frequency comparison's with other phones is what everyone is looking for. I'm sure I forgot another handful of attributes as well. Treble amount being comparable doesnt mean the treble sounds even close between models. No poetry needed.

Ok, I'll try and be patient now :-)

 +1

post #257 of 2918
I'm not exactly what my friend was doing at the end. We did two passes with bits at a time identifying narrow imbalances, the second pass was louder, and once all of those imbalances were evened out, he did a few more quick passes with progressively broader ranges to determine the overall. At the very end, he was making huge sweeps across big swaths of the range.

I've asked him about Fletcher Munson in the past. He explained the principle of upper mids sounding louder, but he didn't go into detail about how he applies it when he's tuning response with tones. I can ask him next time I speak with him if you'd like. He's the real expert on balancing response with tone sweeps. I'm trying to learn all I can from him about it to apply to my home systems.

I generally equalize the long way, using good recordings of acoustic music and lots of back and forth parallel parking of balances. It took me months to balance my 5:1 speaker system. When I was happy with my settings, I had him do a quick sweep on it and he said that I had gotten it as close as it would go with my five band parametric EQ. There were some narrow spikes that could be tamed with more channels, but I don't have the long green for an outboard digital 5:1 equalizer right now. I make do with broad strokes and my AV receiver.
post #258 of 2918
Quote:
Originally Posted by mlxx View Post
 

 

Well he doesn't have to do that does he? Since he is using his own ears.

If they sound flat to your ears then they are flat, that's the whole idea isn't it?

Have to use the compensation stuff when using microphones to measure FR.

 

 

 

 

No, if speakers sound flat to your ears when listening to frequency sweeps, it follows only that they sound flat.  It doesn't follow that they are in fact flat.  According to the equal contour curves, when doing frequency sweeps by ear a speaker must be NONFLAT to sound flat to your ears.

 

It is another issue altogether to listen to a speaker reproducing music (not reproducing frequency sweeps) and to conclude that the speaker is flat because the music sounds just like real, live music.  The speaker must be reasonably flat to reproduce music and give the impression of live music to the experienced ear.

post #259 of 2918
Quote:
Originally Posted by Focker View Post

I don't know that there is no enhancement or attenuation of various frequencies when you hear a live performance, but I do know that my appreciation for live music - just as with speakers and headphones - goes way beyond what just the FR represents. 

I'm with you on that. The creativity of the musical performance and the balance of the mix are first and foremost. But those aspects are on the recording end of the chain. At home on the playback side, the focus is on accuracy and fidelity to the choices made by the folks creating the recording. Professional studios mix using calibrated speakers. If you want an accurate representation of what they created, a calibrated set of headphones or home speakers is the best way to achieve that.
post #260 of 2918

Headphones are not speakers. It's was proven long time ago that headphone's frequency response should't be flat. Actually if it's flat, listeners don't perceive it that way. There are many reseaches on that topic.  Headphone engineers at Sennheiser or Akg are not that stupid. They don't make headphones with flat FR not because they can't not achieve it but because it doesn't make sense.

 

Quote:
Originally Posted by Headphoner View Post
 


Since you determined by ear that the Oppo phones were flat, how did you handle the Fletcher-Munson phenomenon (equal loudness contours)?

 

http://en.wikipedia.org/wiki/Fletcher%E2%80%93Munson_curves

 

The problem is that human ears are not flat (as the equal loudness contours show).  To sound flat to the human ear when doing a frequency sweep, a speaker's response curve needs to be V-shaped.  The human ear is at its flattest with loud response sweeps, but the ear is still not flat--and the speaker must be nonflat to sound flat to the ear. 

 

Hence, to conclude by ear from response sweeps that a speaker is flat would actually be evidence that the speaker is not flat, or so it seems to me.

 

So again, how did you deal with the Fletcher-Munson phenomenon?


It's a good point. What sounds flat at 70 dB  doesnt at 80.  In addition to it we should not forget that every person's hearing is always a little different. And sometimes it's very different, for example many people, especially who are not young, don't hear well high frequencies.  What seems flat for Bigshot it's not that way for other people.


Edited by qazxsw80 - 4/6/14 at 1:19am
post #261 of 2918
Quote:
Originally Posted by Headphoner View Post

1. How open and airy is the sound?
2. Do the phones provide any sound isolation from environmental noise?

Hmmm... I'm not sure what you mean by open and airy. The sound isn't compressed dynamically or muffled if that is what you mean. My ears don't sweat or feel like they're sealed in jars like other headphones I've tried. They're very comfortable for long listening sessions. I could easily forget I'm wearing them.

The isolation from environmental noise is not complete. If the sound is off and someone speaks to you, you can hear them. But obviously with music playing, music is all you can hear. If you are listening to music and someone is standing next to you, they can tell what song is playing. So I guess the sound isolation is partial, not complete.

I apologize if I don't understand the words. I've long been baffled by audiophile terminology. I'm a practical soul. More of a hifi nut than an audiophile.

Does this answer your question?
post #262 of 2918
Quote:
Originally Posted by bigshot View Post


I'm with you on that. The creativity of the musical performance and the balance of the mix are first and foremost. But those aspects are on the recording end of the chain. At home on the playback side, the focus is on accuracy and fidelity to the choices made by the folks creating the recording. Professional studios mix using calibrated speakers. If you want an accurate representation of what they created, a calibrated set of headphones or home speakers is the best way to achieve that.

 

Gotcha, that makes sense. 

post #263 of 2918
Quote:
Originally Posted by bigshot View Post
 

I've asked him about Fletcher Munson in the past. He explained the principle of upper mids sounding louder, but he didn't go into detail about how he applies it when he's tuning response with tones. I can ask him next time I speak with him if you'd like. He's the real expert on balancing response with tone sweeps. I'm trying to learn all I can from him about it to apply to my home systems.
 

Yes, please ask your friend.  I would be interested in his reply.

 

Thanks.

post #264 of 2918
Quote:
Originally Posted by qazxsw80 View Post
 

It's a good point. What sounds flat at 70 dB  doesnt at 80.  In addition to it we should not forget that every person's hearing is always a little different. And sometimes it's very different, for example many people, especially who are not young, don't hear well high frequencies.  What seems flat for Bigshot it's not that way for other people.

 

And that is why you do a lot of subjective testing with the Beta Testers while doing objective testing like measurements to ensure that the final sound signature is great. You have more than one Beta Tester who finds the final headphones to be great, Bigshot is just the one who is doing the most talking.

post #265 of 2918
Quote:
Originally Posted by Headphoner View Post
 

 

No, if speakers sound flat to your ears when listening to frequency sweeps, it follows only that they sound flat.  It doesn't follow that they are in fact flat.  According to the equal contour curves, when doing frequency sweeps by ear a speaker must be NONFLAT to sound flat to your ears.

 

It is another issue altogether to listen to a speaker reproducing music (not reproducing frequency sweeps) and to conclude that the speaker is flat because the music sounds just like real, live music.  The speaker must be reasonably flat to reproduce music and give the impression of live music to the experienced ear.

 

I don't think anyone is talking about if they are "flat", that would be pointless. They are saying they sound flat by ear.

 

So the whole thing is irrelevant.

post #266 of 2918
Quote:
Originally Posted by bigshot View Post


Hmmm... I'm not sure what you mean by open and airy. The sound isn't compressed dynamically or muffled if that is what you mean. My ears don't sweat or feel like they're sealed in jars like other headphones I've tried. They're very comfortable for long listening sessions. I could easily forget I'm wearing them.

The isolation from environmental noise is not complete. If the sound is off and someone speaks to you, you can hear them. But obviously with music playing, music is all you can hear. If you are listening to music and someone is standing next to you, they can tell what song is playing. So I guess the sound isolation is partial, not complete.

I apologize if I don't understand the words. I've long been baffled by audiophile terminology. I'm a practical soul. More of a hifi nut than an audiophile.

Does this answer your question?

Airy means that there is enough "air" produced by each voice and instrument. In essence, a sound/voice is suspended [for lack of a better word] in the air for a short time, enhancing the realism of sound presentation, more akin to a live performance where vocals/instruments echo through the room.

A good way to test this is to cover both cups with your hands. If the resulting sound is then noticeably different/muffled/constrained in contrast with when the cups are unrestricted, it usually means that the air quantity is high, but not always.

Usually the more the headphone leaks the more open it sounds as well.

 

I have a feeling this won't be the most open sounding headphone though... from my experience, speakers don't carry as much openness as some headphones do. YMMV.


Edited by conquerator2 - 4/6/14 at 1:42am
post #267 of 2918
Hold on, the only clean way to do this by ear is not absolute sense but relative. In this case, I was under the assumption you identified deviations from neutral by direct comparisons to your speaker rig at the listening position where it's supposed to be flat.

As others have said, if you go by perceived loudness, it makes no sense whatsoever unless you're using rather close thin bands for evaluation. Loudness curves don't vary drastically with frequency, except if your ears are shot - might then get sharp drops at 4kHz and more or less wide / deep depending on how deaf you are.
I really can't imagine you can do this test practically using pure tones though, it must be hell of a work!
post #268 of 2918
Quote:
Originally Posted by bigshot View Post


Hmmm... I'm not sure what you mean by open and airy. The sound isn't compressed dynamically or muffled if that is what you mean. My ears don't sweat or feel like they're sealed in jars like other headphones I've tried. They're very comfortable for long listening sessions. I could easily forget I'm wearing them.

The isolation from environmental noise is not complete. If the sound is off and someone speaks to you, you can hear them. But obviously with music playing, music is all you can hear. If you are listening to music and someone is standing next to you, they can tell what song is playing. So I guess the sound isolation is partial, not complete.

I apologize if I don't understand the words. I've long been baffled by audiophile terminology. I'm a practical soul. More of a hifi nut than an audiophile.

Does this answer your question?


Airy sound is a sense of space (air) surrounding an instrument playing alone and a sense of space (air) between the instruments when more than one instrument is playing.  Perhaps the opposite of airy is congested.  The term airy is used for both phones and room speakers.

 

The Oppo site says that the phones have open backs.  Open back phones usually provide little or no isolation from environmental noise.  But something someone said earlier in the thread, perhaps you, gave me the impression that the phones provide some isolation.  So I wanted to ask about the degree of isolation from noise in the environment.

post #269 of 2918
Quote:
Originally Posted by qazxsw80 View Post

Headphones are not speakers. It's was proven long time ago that headphone's frequency response should't be flat. Actually if it's flat, listeners don't perceive it that way. There are many reseaches on that topic.  Headphone engineers at Sennheiser or Akg are not that stupid. They don't make headphones with flat FR not because they can't not achieve it but because it doesn't make sense.

It's a good point. What sounds flat at 70 dB  doesnt at 80.  In addition to it we should not forget that every person's hearing is always a little different. And sometimes it's very different, for example many people, especially who are not young, don't hear well high frequencies.  What seems flat for Bigshot it's not that way for other people.

I heard these same arguments when I started calibrating my speaker system. A lot of it just isn't true.

First of all, frrequencies are sound, and flat response is natural sound. An acoustic violin playing on a recording has the same response as an acoustic violin playing live in the room. Balance the volume levels and dynamics, eliminate distortion and push the noise floor below the noise floor of the room and they sound *exactly* the same. Audibly flat response is audibly flat response. If an acoustic violin in person sounds exactly like an acoustic violin recorded, the response is by definition flat. You don't have to apply any corrections. Flat response is critical in acoustic music like chamber music, acoustic jazz and orchestral music. Those of us who listen to live music know instinctively what those instruments are supposed to sound like. (It doesn't matter so much in music where all the musicians plug in, because there is no baseline of "realistic sound" in purely electronic music. But it's still best to be accurate to what the sound engineers intended the mix to sound like.)

Secondly, many of the problems with sound reproduction trace back directly to response imbalances. Frequency masking can mess up clarity and transparency. Masking can also hide the aural cues that indicate depth in a recording. Noise levels in historical recordings are exaggerated by headphones with boosts in the upper mids to give "in your face" sound. Frequency extension is a lot less important than frequency balance to sound quality. If you want deep bass, start with balanced bass.

Thirdly, our sensitivity to frequency imbalances increases as the volume increases. Big spikes in the response in the wrong range can massacre your ears. That's why you EQ in passes, from lower volume to high. If you have time and want to do a really precise job, you start at a low volume and work your way up an octave or two at a time in mmultiple passes until you get to the maximum volume level your ears can stand. But that is going to be a louder sound level than unbalanced, because you don't have a nasty spike sticking up 20dB to shred your ears any more.

Lastly, no matter what your hearing is, flat is flat. If I can't hear about 17kHz, don't ask me to EQ the stuff at the edge of audibility for you. But in the core frequencies, humans are pretty doggone consistent. Even if we weren't, it wouldn't matter because flat response with whatever our ears does to it is exactly the same as natural sound with whatever our ears do to it. Natural sound is natural sound, no matter how we perceive it.

Achieving a balanced frequency response isn't easy. Throwing money at the problem won't fix it. Expensive transducers have the same problems midrange ones do. It takes research and hard work. Figuring out how a parametric equalizer works can be very non-intuitive and difficult. But a balanced response is natural and present sound. It is achievable. And balanced for me is exactly the same as balanced for you.
post #270 of 2918
Quote:
Originally Posted by conquerator2 View Post

Airy means that there is enough "air" produced by each voice and instrument. In essence, a sound/voice is suspended [for lack of a better word] in the air for a short time, enhancing the realism of sound presentation, more akin to a live performance where vocals/instruments echo through the room.

That sounds to me like a clarity issue, which would be a function of either distortion (which these headphones are remarkably free of) or frequency masking (which is eliminated by a balanced response). The attack and decay are exactly as they are recorded. Transient dynamics are super tight.

When I put my hands over the backs of the earcups, I don't hear any difference in sound if that helps.
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