How much power is enough?
Oct 3, 2018 at 4:59 PM Post #91 of 130
I tend to doubt that. Channel separation is the main thing for reproducing soundstage in headphones, and that's generally not a problem. Flappy diaphragms would fall under the category of distortion. Speakers have way more distortion than headphones, yet they reproduce soundstage a million times better than cans. With speakers, it's the room that dictates how good the soundstage is.

The problem with soundstage is that the term is so often misused in audiophile circles that the meaning has gotten lost. Soundstage is the placement of sound precisely in space. That is only possible with speakers, because headphones put sound between your ears, not ahead of you in physical space. "Headstage" is what we talk about with headphones. That is a straight line through the middle of the ears from right to left. The only way to mess that up is to mix the channels, which never happens.



I can't tell if anything you have said contradicts my observation that some headphones obscure soundstage cues. I don't understand the point of what you are trying to get across, unless you want all head-fiers to say "the impression of soundstage" instead of "soundstage," because headphone soundstages are different from speaker soundstages and therefore not real soundstages. Which is really rather pedantic.

Furthermore, "Soundstage is the placement of sound precisely in space. That is only possible with speakers" is entirely your opinion and contradicts the experiences of many if not most headphones users, so I take issue with your stating it as fact. People are going to keep using the word "soundstage" in headphones whether or not you believe it's the correct usage because there are large, generally agreed-upon differences in spatial presentation of different headphones.
 
Last edited:
Oct 3, 2018 at 5:27 PM Post #92 of 130
I'll try and clarify it in more detail... Secondary distance cues are baked into the mix. They get reproduced by mediocre headphones as well as fancy ones. They even get reproduced in mono recordings. A transistor radio can reproduce secondary cues. That isn't soundstage.

Soundstage is the perception of real space... the distance between the listener and the speaker and the left speaker and the right speaker. Those distances create a phantom center that becomes an aural plane 8 feet or more in front of the listener, much like the sound of the band one hears at a concert. Headphones just can't do that. Headphones create a straight line right through the middle of the head and the sound is spread across that line.

There are three types of sound imaging... one dimensional imaging, or headstage is what headphones create- a straight line through the head. Stereo speakers create a more dimensional soundstage- a flat plane of sound a distance in front of the listener. Multichannel speakers create an immersive two dimensional sound field- the listener is in the middle of the plane of sound. Atmos installations create a full three dimensional soundfield- left/right, front/back, up/down.

It's a progression from less dimensional to more dimansional

Headstage: Headphones
Soundstage: Stereo Speakers
Sound Field: Multichannel Speakers

It really isn't just a semantic thing, because it involves actual physical distances... from right on your ears, to a distance in front of you, to all around you. Soundstage and Sound Fields have nothing to do with distortion levels or response curves or any of the things that headphones are dependent on. They're created by the placement of the sound sources in the room itself.

I think the reason that headphone users misuse the term soundstage is because they just aren't familiar with what soundstage is. They use it as a figurative analogy instead of a literal description... a lot like the way they say that sound has "velvety blacks" or "veils". Speaker listeners know what soundstage is, and they know that if they don't have the correct speaker placement and room acoustics, it will totally disappear into smeared around generalized sound, not focused pinpoint accurate soundstage.
 
Last edited:
Oct 3, 2018 at 5:38 PM Post #93 of 130
There are three types of sound imaging... one dimensional imaging, or headstage is what headphones create- a straight line through the head. Stereo speakers create a more dimensional soundstage- a flat plane of sound a distance in front of the listener. Multichannel speakers create an immersive two dimensional sound field- the listener is in the middle of the plane of sound. Atmos installations create a full three dimensional soundfield

What is the point of all this as it relates to the discussion that we were having about soundstage in headphones? Is it that you campaigning to have the word soundstage not used for headphones? Is that the main thrust of your posts? Or are you saying that people who perceive depth in headphones are being tricked? Either way, how is it relevant to what we were talking about?
 
Oct 3, 2018 at 5:46 PM Post #94 of 130
The perception of depth in headphones is a trick. But the trick is performed in the mixing and miking, not in the playback equipment. Secondary distance cues like reflected sound from the recording venue can create a psycho acoustic feeling of depth, but its intensity is probably more dependent on how much attention you are paying to the music, how you feel at the time or what you had for dinner than it is the type of headphones you are using. You can even listen to it in mono and the distance cues are still there.

Here is an experiment... Remove all of the distance cues that don't have anything to do with the headphones- no secondary cues baked into the mix... just play a test tone through your cans. Does it still sound like it's in front of you?
 
Last edited:
Oct 3, 2018 at 6:09 PM Post #95 of 130
The perception of depth in headphones is a trick. But the trick is performed in the mixing and miking, not in the playback equipment. Secondary distance cues like reflected sound from the recording venue can create a psycho acoustic feeling of depth, but its intensity is probably more dependent on how much attention you are paying to the music, how you feel at the time or what you had for dinner than it is the type of headphones you are using.

Why then is it that so many headphones have reputations for a large, small, medium, deep, shallow, three dimensional, distant, or close soundstage size? Are people fooling themselves because they had an expansive feeling dinner into thinking the HD800 has a larger soundstage than their bose in-ears?
 
Oct 3, 2018 at 6:10 PM Post #96 of 130
Could this affect the headphone impedance curve?
curiosity killed the cat but not my hd650. so here it is with some random magnet(from inside a broken hard drive) I really have zero information on its magnetic properties, and I was too lazy to pull the driver completely out, so the magnet was stuck on the backside with a small width of plastic separating it from the driver itself(still enough to hold in place on it's own).
the legends are self explanatory in full size, but just in case: up are the 2 frequency responses with and without the magnet stuck on the back of the driver. and bottom is impedance response with and without magnets.

magnet on hd650.jpg

protective grill removed on the hd650 for access, and pads removed so that no other variations would be involved. the headphone was held in place with some rubber band. I did a measure without magnet before and after to make sure I didn't move the headphone much while placing and removing the magnet and they aligned just fine, so it is fair to assume that the magnet caused those variations on the graph(with the magnetic field and perhaps by changing the open area on the back? IDK).
 
Last edited:
Oct 3, 2018 at 6:12 PM Post #97 of 130
Yes. A magnet could change the value of force factor Bℓ which changes the impedance curve because mechanical impedance Zm of the diaphragm is seen on the electrical side as electrical impedance Ze:

Ze = (Bℓ)²/Zm.​

This means that if Bℓ (magnetic field B) increases/decreases just 10 %, Ze will decrease/increase 21 %. Increasing Bℓ 10 % increases damping ratio (heaphone alone) 21 %.

Would this effect cause the whole impedance curve to raise/lower uniformly maintaining its shape or could it impact different frequencies differently?

My listening experiments suggest that stacked magnets seem to have greater effect on the bass and treble of my headphone, although I'm not entirely sure yet... the impedance curve of my 300ohms GMP is relatively similar to the HD6x0. There's a very obvious influence on the sound, it affects the whole sound and presentation slightly.
 
Last edited:
Oct 3, 2018 at 6:18 PM Post #98 of 130
Why then is it that so many headphones have reputations for a large, small, medium, deep, shallow, three dimensional, distant, or close soundstage size? Are people fooling themselves because they had an expansive feeling dinner into thinking the HD800 has a larger soundstage than their bose in-ears?

Yes. They're applying better performance in other aspects like response and distortion and dynamics to a term that is irrelevant. It's not that they are hearing things. It's that they don't know how to describe the improvement they're hearing. Not uncommon among audiophiles. The primary problem impedance mismatches can create is a lower signal. People tend to read this as poorer sound quality. But it can also affect response and dynamics. It's pretty clear what an underpowered set of cans would sound like. Soundstage is usually used as a very general term describing a subjective impression of how good music sounds, not a specific one. But speaker placement, room acoustics and channel separation are the factors that actually impact soundstage.
 
Last edited:
Oct 3, 2018 at 6:20 PM Post #99 of 130
curiosity killed the cat but not my hd650. so here it is with some random magnet(from inside a broken hard drive) I really have zero information on it's magnetic properties, and I was too lazy to pull the driver completely out, so the magnet was stuck on the backside with a small width of plastic separating it from the driver itself(still enough to hold in place on it's own).
the legends are self explanatory in full size, but just in case: up are the 2 frequency responses with and without the magnet stuck on the back of the driver. and bottom is impedance response with and without magnets.



protective grill removed on the hd650 for access, and pads removed so that no other variations would be involved. the headphone was held in place with some rubber band. I did a measure without magnet before and after to make sure I didn't move the headphone much while placing and removing the magnet and they aligned just fine, so it is fair to assume that the magnet caused those variations on the graph(with the magnetic field and perhaps by changing the open area on the back? IDK).

Ah! Finally someone measures it. Thanks a lot. This correlates relatively well with what I hear on my GMP with stacked magnets. I perceive a slightly lower mid-bass quantity (but seemingly faster/tighter) and this coupled with the other changes on the sound creates a slight change in presentation.

There's actually a thread where the effects of magnets have been discussed recently here.

I'd LOVE to see how this affects THD and impulse response.

EDIT: I'm guessing that the magnet you used is not particularly powerful (err, actually the small distance to the driver is likely causing the very subtle effect, it would be more drastic if it were touching) because the effect I hear is even more dramatic on the FR (effects vary with magnet strength). I'm using N45 12mm neodymium cubes, scarily powerful things.. and kinda dangerous near a driver. Polar orientation matters, though. The wrong orientation (++ or -- instead of opposites) will have detrimental effects on the driver, causing what I perceive to be a severely underpowered (or underdamped) performance, especially at the frequency extremes.
 
Last edited:
Oct 3, 2018 at 6:33 PM Post #100 of 130
Yes. They're applying better performance in other aspects like response and distortion and dynamics to a term that is irrelevant. It's not that they are hearing things. It's that they don't know how to describe the improvement they're hearing. Not uncommon among audiophiles. The primary problem impedance mismatches can create is a lower signal. People tend to read this as poorer sound quality. But it can also affect response and dynamics. It's pretty clear what an underpowered set of cans would sound like. Soundstage is usually used as a very general term describing a subjective impression of how good music sounds, not a specific one. But speaker placement, room acoustics and channel separation are the factors that actually impact soundstage.

Ok, so what exactly do we as a community gain by separating soundstage and headstage as terms? If they are not technically correct (and please do give a citation for the proper definition of soundstage that you have put forward) what do we as a community lose by using soundstage instead of headstage?
 
Oct 3, 2018 at 7:12 PM Post #101 of 130
Ok, so what exactly do we as a community gain by separating soundstage and headstage as terms? If they are not technically correct (and please do give a citation for the proper definition of soundstage that you have put forward) what do we as a community lose by using soundstage instead of headstage?

The difference between headstage and soundstage lies in how you fix problems with them.

If you have a problem with headstage, your problem relates to the secondary depth cues embedded in the music. You could add an outboard reverb/crossfeed to create synthetic depth cues, or just listen to music with more secondary depth cues recorded and mixed into it.

If you have a problem with soundstage, you would want to consider the things that help headstage, and in addition check your room acoustics to see if room reflections are muddling up the directionality of the sound. You could also move the position of your furniture and speakers around to tighten up the phantom center.

To sharpen up a sound field, you would want to consider all of the things you considered for headstage and sounstage, and also consider DSPs that create sophisticated timing shifts to create a rich room ambience.

The pioneer of sound stage (aka sonic stage) was John Culshaw, a record producer for Decca. He produced Wagner's Ring cycle in the late 50s through the mid 60s with a revolutionary technique- he placed the singers on a stage with a grid painted on it and had them move around the grid to follow the blocking while stereo microphones captured them in precise alignment in the stereo spread. When played on a speaker system with good soundstage, you can close your eyes and precisely localize the individual singers by sound alone. The effect is like being in the opera house with the stage in front of you... hence the term "sound stage". More info on Culshaw here... https://en.wikipedia.org/wiki/John_Culshaw
 
Last edited:
Oct 3, 2018 at 7:36 PM Post #102 of 130
Ah! Finally someone measures it. Thanks a lot. This correlates relatively well with what I hear on my GMP with stacked magnets. I perceive a slightly lower mid-bass quantity (but seemingly faster/tighter) and this coupled with the other changes on the sound creates a slight change in presentation.

There's actually a thread where the effects of magnets have been discussed recently here.

I'd LOVE to see how this affects THD and impulse response.

EDIT: I'm guessing that the magnet you used is not particularly powerful (err, actually the small distance to the driver is likely causing the very subtle effect, it would be more drastic if it were touching) because the effect I hear is even more dramatic on the FR (effects vary with magnet strength). I'm using N45 12mm neodymium cubes, scarily powerful things.. and kinda dangerous near a driver. Polar orientation matters, though. The wrong orientation (++ or -- instead of opposites) will have detrimental effects on the driver, causing what I perceive to be a severely underpowered (or underdamped) performance, especially at the frequency extremes.
even under the bests of conditions, my cheap rig isn't clean enough to measure THD. and this was far from ideal, I didn't bother calibrating the loudness and I used my usual computer with fans partly responsible for all the sharknados and the noise that comes with them. it's unusable.

I guess there is no harm showing impulses, although you can readily see how I wasn't paying any attention, as I managed to perform magic and measured a signal a good deal before it was sent. I'm that good^_^. (I'm guessing it's a bug from forgetting the time alignment thingy).
IR-hd650-magnet.jpg
no idea how or what to interpret there.
 
Oct 3, 2018 at 7:53 PM Post #103 of 130
The difference between headstage and soundstage lies in how you fix problems with them.

If you have a problem with headstage, your problem relates to the secondary depth cues embedded in the music. You could add an outboard reverb/crossfeed to create synthetic depth cues, or just listen to music with more secondary depth cues recorded and mixed into it.

If you have a problem with soundstage, you would want to consider the things that help headstage, and in addition check your room acoustics to see if room reflections are muddling up the directionality of the sound. You could also move the position of your furniture and speakers around to tighten up the phantom center.

To sharpen up a sound field, you would want to consider all of the things you considered for headstage and sounstage, and also consider DSPs that create sophisticated timing shifts to create a rich room ambience.

The pioneer of sound stage (aka sonic stage) was John Culshaw, a record producer for Decca. He produced Wagner's Ring cycle in the late 50s through the mid 60s with a revolutionary technique- he placed the singers on a stage with a grid painted on it and had them move around the grid to follow the blocking while stereo microphones captured them in precise alignment in the stereo spread. When played on a speaker system with good soundstage, you can close your eyes and precisely localize the individual singers by sound alone. The effect is like being in the opera house with the stage in front of you... hence the term "sound stage". More info on Culshaw here... https://en.wikipedia.org/wiki/John_Culshaw

"If you have a problem with headstage, your problem relates to the secondary depth cues embedded in the music." You've just said in a previous post that headphone characteristics such as distortion and dynamics affect what other people term soundstage. You say this is because they are using the word wrong. Still, this means that other things affect the secondary depth cues besides how the music is recorded. If you are interested in using language clearly, why do you seem to be contradicting yourself here?

The word headstage doesn't make sense to me. My head doesn't feel like it's changing shape. It doesn't sound like the music is in my head. Why should headphone users adopt this term when it's obvious that we aren't using speakers or speaker soundstage techniques? What problem does the use of the word headstage solve?
 
Last edited:
Oct 3, 2018 at 8:12 PM Post #104 of 130
Try to understand what I'm saying here. This isn't a contest. I'm just trying to share information with you.

All of the distance you're perceiving in music played through headphones is due to secondary depth cues embedded in the recording itself. These distance cues are created by the way the mikes are placed and the way the music is mixed. Your brain is interpreting the cues in the music and creating an impression of space. But that space only exists in the recording. It isn't real. If you play a test tone without those cues through the exact same headphones, your brain won't bet fooled by the secondary depth cues in the recording. And the sound will be revealed to be smack dab in the middle of your head where it's been all along. It's all in your head- hence the term headstage.

The sensation of depth isn't because of the headphones you are using. There is no space when you stick sound directly in your ears. The differences between headphones primarily involve frequency response, distortion levels and dynamics. When people hear good response/distortion/dynamics, they say that they are hearing better soundstage. But they aren't. They are just hearing better sound. Audiophiles use the term soundstage incorrectly because they don't really understand what soundstage is and how itt's created.

If you hear a recording like Culshaw's Ring on a good speaker system, you can close your eyes and locate objects in space in front of you. The physical distance between you and the speakers and the effect of the room around the sound create tangible space. When you listen to it, the sound is exactly like sitting in the opera house in the fifteenth row with the singers moving around on the stage in front of you. That is soundstage. If you listen to Culshaw's Ring on headphones, you don't get the same effect at all, because the stereo spread was designed to match the scale of a typical stereo system with speakers 8 feet apart and the listener 8 to 12 feet away from them. Those distances are a vital part of recreating the soundstage of a concert hall.

Is that clearer?
 
Last edited:
Oct 3, 2018 at 8:23 PM Post #105 of 130
even under the bests of conditions, my cheap rig isn't clean enough to measure THD. and this was far from ideal, I didn't bother calibrating the loudness and I used my usual computer with fans partly responsible for all the sharknados and the noise that comes with them. it's unusable.

I guess there is no harm showing impulses, although you can readily see how I wasn't paying any attention, as I managed to perform magic and measured a signal a good deal before it was sent. I'm that good^_^. (I'm guessing it's a bug from forgetting the time alignment thingy).

no idea how or what to interpret there.

Very cool! I'm not competent enough to interpret it either, but I guess it makes sense to see that the residual ringing after the 'overshoots' appears to want to settle down slightly faster with the magnet. Otherwise, I'd expect this ringing to shift to a higher frequency (assuming correct pole orientation), but I'm just speculating...

Nice effort, though! At least, now we have a tentative measurement.
 
Last edited:

Users who are viewing this thread

Back
Top