What is "imaging" in headphones?

Audio Science
1

This is another topic, along with a number of other audiophile-friendly terms, which came up in the 5-31-25 Noise Floor livestream. So thought I’d put the question out for others to comment on.

I think of this as just “stereo imaging”. How clear of a picture is formed in my head by the soundscape? Do sounds seem to be coming from the right directions? Are they well separated?

The main characteristic I look for, for this effect, is good symmetry. Are the drivers well matched in volume and in timbre (frequency response)? I’ve owned at least a couple headphones where the drivers were not that well-matched for various reasons. And without good matching/symmetry, vocalists and dialogue often seem off center. The direction of sounds is less precise. The stereo soundscape isn’t as clear.

I think things like distortion, frequency response, dynamic range (high SNR), and the openness of a headphone can also effect the imaging. And how clear and nuanced the stereo image or soundscape is. They also effect how broad, spacious, or narrow the soundscape is, though I suspect this is what many audiophiles refer to as “soundstage”.

1 Like
2

A couple takes from some other folks.

3

Yeah this is one of those that really should have a well-understood meaning, but when people talk to me about it I regularly don’t know what they’re referring to. One person’s imaging could be another person’s detail, could be another person’s sound stage… It all feels like it’s being led by various reviewer language, mine included, and then churning out mostly semantic confusion. It’s why I prefer to evaluate just on FR characteristics, but people always seem to want me to translate that into my private language for some reason.

2 Likes
4

In simple terms, I hear imaging quality as following from precise control and low noise in the high frequencies. A louder high range increases perceived detail, but it may not be precise enough to hold locations. Consider the KEF LS 50 and Utopia.

Sound stage is the mushy term, and often unintelligible from others.

1 Like
5

Soundstage is actually a very precise term, although it can be confusing (@generic) as it is measured in several ways. Like temperatures, which reference the freezing point of water. However there are several systems of measurement.

The Imperial Soundstage is defined as:
Sennheiser HD-600 - generic IEM = 1 ISU :phone:

The American Soundstage is defined as:
Sennheiser HD-6xx - generic IEM = 1 ASU :phone: :phone:

The Metric Soundstage is defined as L
Sennheiser (HD-800 - HD-600) = 1 MSU :phone: :phone: :phone:

In recent months, due to the closure of the American Standards Department and subsequent removal of the headphones by a member of the DOGE team working on waste, fraud and abuse, it has been proposed to redefine the ASU using American made wireless components, if they can be found. This has caused controversy in the press.

:phone: Imperial Soundstage Unit . Note that in some parts of the world (the EU) the ISU is referred to as the ESU or English Soundstage Unit

:phone: :phone: The American Soundstage Unit

:phone: :phone: :phone: The Metric Soundstage Unit. Note that in the EU, this is often called the ISU or International Soundstage Unit.

5 Likes
6

OMG. Thanks for the clarification! :rofl:

7

It is hard for me to separate imaging and soundstage as well. In part because I don’t really use the latter term much. There are alot of different ways you can think about this stuff though. And I don’t say that mine is necessarily more correct than some others.

When it comes to the quality of the stereo imaging though, I think everything can potentially get into the act (to use an apt Floyd-ism). So yes, the clarity of the image is important. The precision of the image is important. The spaciousness, width, depth, height (in some cases), dimensions, and general immersiveness are all important. And imo, these can all potentially encompass more than just your basic FR.

But even if it is mostly related to FR, I think it does a bit of a disservice to think of it just in those somewhat narrow terms, because the quality of the stereo image can potentially be affected or impacted by so many different things in a headphone’s and transducer’s design and usage.

The openness of a headphone, for example, isn’t really related to FR. I think most would agree though that open headphones tend to image better than closed headphones.

Symmetry is certainly related to FR. But you can’t look at a single FR curve for a headphone, and really get much of an idea of its symmetry or imaging just from that. To really get an idea of a headphone’s symmetry, you have to look at both the left and the right channels, and compare the differences in their FR and relative amplitude, which is not a trivial thing.

The symmetry you hear in a headphone can also be affected by other components in your audio setup. Especially the amp, which may tend to drift a bit to the left or right at different volumes. So if you want good symmetry (and imaging), then you also have to pay some attention to what’s going on in your other components, particularly in terms of their left-right stereo balance. But also in terms of noise, distortion and impedance, for the best results.

If your headphones don’t image well to begin with though, then they probably aren’t very good headphones! And the most you can probably do to try to fix it is maybe add some EQ, which has potential upsides and downsides of its own. That is how important good imaging is though, imho.

It really is sort of the whole ball of wax, when it comes to sound quality in headphones. And it’s what separates an average or mediocre headphone from a really good one, imho.

8

I know what I mean by imaging, but it’s based on about half a century of listening to audio gear of all sorts of quality levels, and much of it during times when it was next to impossible to discuss it, like on here,'cos the internet didn’t exist let alone forums.

So, it’s just what I took it to mean, and I’m too old a dog to even try to adjust my perspective on such terms now.

To me, imaging pretty much means … if I close my eyes, can I kinda picture where, in front of me, are the various things I can hear? Can I pick out one instrument’s location from another, and any vocals from instruments? The more I can do that, the better the imaging.

It’s not the same (to me) as soundstage, but they’re related.

It’s sort-of like, as a metaphor, if I’m looking through a glass windscreen, is the glass clean and clear,or is it diffused by raindrops. Or have I just been sprayed by muddy water from a passing lorry.

And yes, private language problem. I get your point. But it’s what it means to me, with the benefit I don’t need a ‘translation’ engine between myself and someone(s) else, because I’m not trying to relate what I hear to others. I’m not, thank goodness, reviewing headphones. I do not envy you that task. :smiley:

2 Likes
9

If you’re only listening to higher quality headphones, then it may be harder to find and discuss the perhaps more subtle distinctions between them on imaging. Because they may all deliver at least passable quality in this regard.

It isn’t hard to find headphones that image more poorly though. I have listened to many of them. And just about any two-bit DJ/studio headphone with polyester drivers would likely do the job, and help to ground some of your perceptions a bit more on this.

On-ears might also be good, since they interact with less of the pinna.

If you have an AKG K361 around (which is technically “over-ear”, but with smaller cups), you might give that a listen, and compare its level of clarity, precision, and sense of dimension/spaciousness to some of your better headphones. Some of the lower-end, closed-back, AudioTechnicas might be good for that as well. I think I auditioned most of the M series. And as you go down, each one seemed a little worse at imaging, though maybe in slightly different ways. (The ATs are also usually described as “over-ear”, but also have very small cups, which sit half on and half off of my large ears.)

The difference between the M50X (which has passable imaging for a closed back) and M40X was somewhat subtle. The M40X has alot of high frequency detail for example. But it also has higher distortion, which tends to shrink the stereo image to my ears and make it less distinct.

Some of the Beats on-ears that I tried back in the day, also had pretty small/narrow images, even though they had pretty smooth FR and decent extension (though were definitely on the warm side, FR-wise). I haven’t tried any of the newer Beats though, so they may have improved some.

I haven’t listened to a Sony MDR-7506 in awhile. But that may also be another possibility. The 7506 has decent bass FR, and is a bit strident in the upper frequencies in spots. It also has small cups for an over-ear though. So it was more like on-ear for me. And it doesn’t have alot of air in the very high frequencies. And I suspect it was not that great for imaging as well.

Maybe some of the lower end Sennheiser headphones would also be good for finding some perspective. There are many others that are out there that would probably be just as good or better though for something like this.

I am directing these comments to both Saracen and Resolve btw.

1 Like
10

Your “imaging” rationale is solid and sound. However, an inversion this snippet expresses a retrospect that aligns with mine.

One person’s imaging could be another person’s detail, could be another person’s sound stage… It all feels like it’s being led by various reviewer language, mine included, and then churning out subjective perfection. It’s why I prefer to not evaluate just on FR characteristics…

1 Like
11

I find your point of bass heavy or warm headphones relevant to valuing an imprecise inconclusive definition. When listening to warm Sony headphones, (or other characteristic headphone) I find that I am seeking and enjoying a different type of imaging. Therefore, I postulate that imaging and preference of imaging is not static and therefore may benefit from not falling under a universal comprehensive collective definition.

1 Like
12

Amps can greatly affect imaging. My Lyr 3 ranges from near “mono” to medium imaging and soundstage per the tube, with the same drivers. Channel separation and noise are important.

1 Like
13

I couldn’t agree with you more on an amplifiers effect on imaging. When it comes down to recreating spacial cues that will fool my brain into a preferred illusion of image and stage, I have to find which amplifier or tube will work the most magic for each headphone. I obsess over this and have spent countless hours of my life plugging and unplugging gear to listen for each headphone. This is one of the reasons (besides being a gear hoarder) that I collect amplifiers and why I own multiple tube amplifiers of the same make.
.
However, I have not been observant enough to discern effects of channel separation and noise though. If either less or more will benefit imaging and stage, then I am good either way. I know that you on the other hand are observant of much more than I. One example of many is when you pointed out a while back something along the lines that longer tubes tend to have a warmer or bass heavier characteristic to their shorter brethren. I realized that in my thousands of tube comparison sessions I had never observed this generalization until you stated it. I have learnt so much from others in headphone forums that I would have missed on my own.

1 Like
14

  • More metal mass in a straight-walled tube generally sounds warmer and richer than less mass or a smaller internal build. GE tubes = lean and bright.

  • A Coke bottle tube with a stepped shoulder tends to have more perceived air and “space” than a straight-walled tube. I was quite underwhelmed by the sound quality of my Bottlehead Crack using the factory straight tube, but even a basic $10 or $20 Coke bottle power tube makes a big difference.

1 Like
15

IME imaging (clarity and separation of panning cues) is entirely down to errors of the headphone’s response above 1 kHz relative to the listener’s HRTF—provided there aren’t any massive masking factors below 1 kHz like a massive bass shelf or sucked out midrange.

I go into this in my article about Soundstage (scroll down to “Image Separation”) but I do wish people paid more attention to this section at the end of this (admittedly, unmercifully long) article, because imaging is 100% solved for me by accounting for and fixing the aforementioned error and I think others would probably enjoy fixing it for themselves too.

1 Like
16

I find I listen to the Lyr 3 most of the time with the LSSST, not at tube at all. Perhaps that’s why. Some tubes get gooey and yes sound less stereo. The PSVANE is pretty darn good, and while I think it SHOULD be better than the LSSST FET device, I still find myself listening to it less.

In the end, I think it’s that choice that is definitive.

17

Chesky Records has several demo discs available that illustrate all the different audiophile phrases quite well, supported with musical examples.

This album, for example, but there are several more.

4 Likes
18

I get the Chesky demos, but have them on CD or FLAC. Do they really work over YouTube? Standard YouTube, not paid hi-fi?

19

I have no reason to doubt that others might enjoy fixing that (and yes, I read it), but speaking personally, my interest in headphones is simply about enjoying listening to music. It’s solely about that experience. It doesn’t much matter to me why my perception of imaging (or other subjective descriptions) sound as they do, merely that (to me) they do.

If I had to bet, I’d bet that among the membership of this forum, there will be a higher proportion of people interested in the what and why of “imaging” (etc), and exactly what it means, but I’d also bet that among the general mass of headphone-buying consumers, most would be much closer to my position of not much being interested in why, merely in the experience of listening to their music.

Given that on top of all the other issues in trying to communicate what a headphone sounds like, including with FR, it seems to me that not having a commonly accepted and understood definition of things like imaging, is a major problem.

Which brings me to the really big question … who are reviews of headphones (and other stuff) intended to be consumed by? For the cogniscenti that would follow that description (in the article), that approach is valuable and interesting, but among general headphone consumers and buyers, certainly among those I know, their eyes would glaze over at such a technical description of ‘imaging’.

I’d say there’s a heck of a language gap involved here, and probably much bigger than even I thought it was, if we can’t even understand what everyone else means by such subjective terms. And it appears we can’t. Sadly, I have no idea what can be done about that, either.

1 Like
20

I tried it with Tidal, YouTube was used for illustrative purposes only.