Soundstage, Imaging, etc

[zenki]

If say a listener, C, has some distance, d, to an audio source, I1-I13; then is:
1) d = perceived distance from C to I1/I2/I3 => soundstage
2) the perceived location of I1-I3 = imaging eg. top-left, bottom-right etc

Any experts can elaborate?

 

[Absolute]

Not sure it's easy to understand what exactly you're asking about, are you looking for definitions for soundstage and imaging?

 

[Jimbob54]

I've always understood Soundstage to be the width of the perceived stage the instruments are on. So headphones which make you think there are just 2 speakers strapped to your ears, nothing outside that, have v narrow Soundstage. Imaging is how well the instruments lock to a point in that stage

 

[Jimbob54]

I've always understood Soundstage to be the width of the perceived stage the instruments are on. So headphones which make you think there are just 2 speakers strapped to your ears, nothing outside that, have v narrow Soundstage. Imaging is how well the instruments lock to a point in that stage

Sometimes there is a depth to the Soundstage too, feeling you are either up close and "in" it, or further back. Also sometimes a depth of field so instrument 1 is closer than 2.

 

[Vini darko]

Answer is it depends. The stereo illusion is dependent on speakers their placment in the space , the space itself and listening position reletive to the speakers and space.

 

[Vini darko]

This video may help with getting your speaker placment reletive to listening position optimised.

As for the room itself they need to be tackled on a case by case basis. There's many threads here about room treatment.

 

[Absolute]

For me, soundstage is the perception of 3D-space all around you (easier if you close your eyes) and imaging is how distinct and stable certain things appear on this soundstage, in terms of placement, size, distance and clarity.

These things are just an illusion, a work of fiction made possible due to how our brain work. The quality of these things is highly related to timing and phase behavior and will therefore depend on speaker dispersion pattern, frequency response at all angles, distance to boundaries such as walls on all sides and the spectral content of all these reflections.

By changing the distance to either a boundary or a sound source you will change how this illusion transpires in your head because you're changing the relationship between direct and reflected sound as well as the timing (and phase interaction) between the two.
Aside from room effects, many different effects can be created through creative frequency response, delays and phase manipulation from the sound engineer while mastering.

The biggest discovery I've made through personal experience is that low frequency content affects the perception of soundstage hugely. Don't underestimate the importance of the lowest octave for sheer realism.

 

[andreasmaaan]

If say a listener, C, has some distance, d, to an audio source, I1-I13; then is:
1) d = perceived distance from C to I1/I2/I3 => soundstage
2) the perceived location of I1-I3 = imaging eg. top-left, bottom-right etc

Any experts can elaborate?

I'm not sure what L1-L13 stands for. Is this a point source? Or a speaker with multiple drivers? Or the whole audio reproduction system? Or perceived "objects" within a recording?

And by "=>" do you mean "greater than or equal to"?

The size and depth of a soundstage will always be not only loudspeaker and room dependent, but also program and listener dependent.

But yes, imaging is about the perceived location of "objects" within a soundstage.

 

[Jimbob54]

I'm not sure what L1-L13 stands for. Is this a point source? Or a speaker with multiple drivers? Or the whole audio reproduction system? Or perceived "objects" within a recording?

And by "=>" do you mean "greater than or equal to"?

The size and depth of a soundstage will always be not only loudspeaker and room dependent, but also program and listener dependent.

But yes, imaging is about the perceived location of "objects" within a soundstage.

I took I to be Instrument 1 etc

 

[andreasmaaan]

I took I to be Instrument 1 etc

Ah! I read it as a small "L", not a capital "I".

Ok, then in answer to the OP, IME "d" is not exactly soundstage, but related to it.

Soundstage refers to the perceived extent (height, width and depth) of the stereo image. Imaging refers to the location and stability of "I1-I13" (usually referred to as "objects") therein.

 

[Jimbob54]

Ah! I read it as a small "L", not a capital "I".

Ok, then in answer to the OP, IME "d" is not exactly soundstage, but related to it.

Soundstage refers to the perceived extent (height, width and depth) of the stereo image. Imaging refers to the location and stability of "I1-I13" (usually referred to as "objects") therein.

A far better answer than my stab at it!

 

[tuga]

Stereophile's glossary may help with the terminology:

image See "phantom image."

phantom image The re-creation by a stereo system of an apparent sound source at a location other than that of either loudspeaker.

imaging The measure of a system's ability to float stable and specific phantom images, reproducing the original sizes and locations of the instruments across the soundstage. See "stereo imaging."

stereo imaging The production of stable, specific phantom images of correct localization and width. See "soundstaging."

soundstaging, soundstage presentation The accuracy with which a reproducing system conveys audible information about the size, shape, and acoustical characteristics of the original recording space and the placement of the performers within it.

 

[Blake Klondike]

The thing that strikes me about sound stage and imaging is what a tremendous difference it makes if you get it right. I have had many "what's the big deal here?" reactions to a pair of speakers and then moved three inches to the "sweet spot" and had the sound just come alive. Problem for me, and possibly many others, is that I don't have a dedicated listening room, so it is an eternal battle to try and maximize this aspect.

I find myself listening to HD800 a lot because headphones are so straight-forward, but I find I miss the speaker experience, as well.

 

[pozz]

If say a listener, C, has some distance, d, to an audio source, I1-I13; then is:
1) d = perceived distance from C to I1/I2/I3 => soundstage
2) the perceived location of I1-I3 = imaging eg. top-left, bottom-right etc

Any experts can elaborate?

When you're doing ray tracing simulations of rooms, it's not just one d but thousands of ds.

This is obviously for a concert hall. I couldn't find one for a home living room.

The chart with the green spikes you see in the lefthand corner is the expected energy time curve (ETC) according to the model (amplitude on y axis, time on x axis). You can see there's an initial spike (tallest, first to the left), early and late reflections (lower, coming in clumps back to the listening position), depending how far the sound source is from walls, ceiling and so on. It's representation of how a short, sharp sound will decay over time in your room.

In concert hall acoustics one of the psychoacoustic properties they try to nail down is apparent source width (ASW), which refers to a listener's perception of the size of the sound coming from the stage. It's exactly the same problem on a different scale in living room with a stereo setup.

Stereo cannot convey height information, just left and right. You might get height differences at certain frequencies because of reflections from your furniture. Same goes for left and right images, which is why symmetry is so important (most of the time it doesn't matter because the mess of sound reflections is so thick that small differences disappear; although they might reappear again if you decide to treat your room with absorbers).

The strength of sound coming directly from your speakers to your listening position, and the relative strength of sound coming from all other sides, including behind you, will affect the perceived size of soundstage and images in it. Remember that speakers fire in all directions, but not with equal power in all directions.

The discussions on ASR about speaker dispersion concern not just tonal differences, but also differences in imaging, since the speaker's radiation pattern across the audible range is a key part to how it will energize your room and in turn affect your experience.

 

[tuga]

This is obviously for a concert hall. I couldn't find one for a home living room.

Have you tried this:

https://amcoustics.com/tools/amray

 

[pozz]

Have you tried this:

https://amcoustics.com/tools/amray

I've looked at it and other freeware sim software before. They give you an idea of what's going on but don't replace in-room measurements. Too many factors affect the outcome, even for bass, which is supposed to be easier to model. Take distance from listening position to walls: there are apparent boundaries (drywall, which bass will pass through) and actual boundaries (concrete or brick external wall, which will pass far less), some distance away.

 

[zenki]

Sorry didn't make it really clear. I1-I3 is supposed to be acoustic instruments eg. piano, violin etc.
=> is arrow.
I mainly use IEMs so some factors may not apply but from the responses, more or less, got the gist of it.

Thanks all.
Anyone else who wants to chip in, feel free.

 

[tuga]

Left is mic/recording, right is speakers/reproduction:

 

[tuga]

 

[Snarfie]

A sort of audio dictionary compiled by Steve Guttenberg


He describe at minute 16:40 staging quite well IMO. For me it's a vail that is dropped. Suddenly you notice the difference immediately the band is playing like a band intimate. This staging information must be in the recording not something a speaker makes up.