Properties of speakers that creates a large and precise soundstage

[STC]

Not sure how you got convinced you needed 26 speakers to listen to stereo recordings. I know you are far from the only one, particularly at ASR, many seem convince they can do better with more speakers.

You can read here.

AMBIOPHONICSThe Synthesis of Concert-Hall Sound Fields in the Home

by Ralph Glasgal The stereophonic method of reproducing two-channel recordings has had a run of some 65 years. Now, it even has a new lease on life in the form of surround sound, where the left, ri…

ambiophonics.wordpress.com

https://ambiophonics.wordpress.com/2023/08/05/envelophonics/

If you were a member of AES you could have visited to such demo which was included in the technical tour. Too bad the institute is closed now.

It is audiophiles myth that only two speakers are needed because human got 2 ears.

 

[Tim Link]

How much does a wave guide has an impact on the soundstage?

I've been experimenting with a few different waveguides. My general impression is that narrower dispersion gives a more distant effect. Works good with orchestral recordings. But I tend to prefer a wider dispersion from the waveguide. I think some dispersion control is better than going full wide with no waveguide, although it can depend on the room.

This is the narrowest horn I've tried: https://www.parts-express.com/pedocs/specs/264-315--hl14-25-spec-sheet.pdf

Overall I like this one better: https://www.parts-express.com/SSP Applications/PartsExpress@SuiteCentric/SCA 2019.1/img/270-318_HR_0.default.jpg?resizeid=104&resizeh=600&resizew=600

The wider dispersion adds some vibrance and envelopment to the listening space, makes a lot of recordings sound prettier and I'm still getting a nice, wide soundstage.

They can both sound very good and natural so long as you cross them over to the lower frequency drivers in a way that produces a smooth off-axis response.

 

[test1223]

I posted it earlier but try “Two Weeks” by FKA twigs. The song isn’t great but there is a staccato effect that begins around 51 secs that sounds well above the rest of the soundstage on my speakers. It’s the only stereo recording that I’ve heard any sort of “height” in.

I recently learned that there are some songs with slightly higher shifted sound events. But I don't know any recording with a big (bigger) vertical sound event.

 

[Tim Link]

I recently learned that there are some songs with slightly higher shifted sound events. But I don't know any recording with a big (bigger) vertical sound event.

I have a binaural recording that features airplanes flying overhead. Those seem to go right over me, and it works on just about every stereo system I've tried it with.

Various - Audio - Stakkato Spezial

View credits, reviews, tracks and shop for the 1989 CD release of "Audio - Stakkato Spezial" on Discogs.

www.discogs.com

 

[STC]

I can never get over my visual bias.

Exactly. Our hearing evolved for survival not fill in our imagination. Music supposed to do that.

I have to listen in total darkness or eyes closed for that to happen. When I turn the lights on it can be surprising to see a ceiling or wall closer than where there was a sense of sound. With the lights on I can never get over my visual bias.


For me, sensation of sound in my ears or inside my head (some call it headphone effect I guess) only happened in a space with a great excess of absorption. Others have reported the sensation with very narrow dispersion speakers.

Regarding sound beyond walls see my comment above.

That is incorrect because pinna’s role is to externalize sound. Unless you do not have pinna ( outer ear) you will hear the sound outside you head because pinna functions as a direction finding mechanism.

Is there even such a thing as "conventional stereo"? I have no idea what that would mean. Based on one of your earlier posts you may have in mind a generic stereo mic with no spacing to capture the inter aural delay/phase relationship... But I wouldn't call such a simplistic approach "conventional", I'd call it ineffective.

Space is captured or conveyed with the amount of reverberations in the recordings. Unless the stereo mics is spaced around 17 cm, the ITD information is wrong. XY configuration mics do not have ITD at all.

There are so many different microphone types and recording configurations that capture phase/delay information that can recreate a spacious sound during 2-channel playback, oftentimes including more than just two microphones. However, just because it takes expertise and creativity to capture a compelling stereo soundfield doesn't mean it's a trick or somehow not stereo. Artists and engineers finding ways to maximize the capabilites of the playback system (including various electronic processing) is part of the creative process and it increases the pleasure of listening. Just because it takes creativity doesn't somehow make the result less enjoyable.

Nothing wrong with that. The topic is soundstage of stereo and whether speakers can improve that. What I am reading so far there is confusion with sound stage, imaging and spaciousness.

There's a stereophile test CD that captures the same scene with different microphone setups. In a highly overdamped room, I would get a sense of depth, sounds behind me, and the sensation of the sound nearly brushing my left ear when they walked back-to-front past the microphone, but it was never wider than the speakers. In a reflective room, there was depth, and the sound was wider than the speakers, but I didn't get the illusion of sound behind me or brushing past my ear. So it seems to me to be very much dependent on the room; unless we listen outside, in anechoic chambers, or highly overdmped spaces, the room is possibly the greatest factor in creating or destroying certain illusions, at least once some minimum level of competently designed speakers are in use.

I have a SACD of piano recordings made by different mics. And When one started to talk about the correct sound of piano and what not I ask them to explain the difference in the piano sound and which one supposed to sound like real piano.

There are absolutely aspects of truth to this for me. For example, see my earlier comments about 'finding my seat in the audience'.

When I heard sound behind me using the stereophile CD I suspect there was enough ambiguity in the soundfield (due to the excess absorption hiding room cues) that knowing the sound was coming from the back was enough information to let me interpret the sound as coming from the back as well; but once it happened, the sensation was real. Just like some optical illusions can let you see two entirely different pictures depending on what you focus on, having a mental predisposition can help the perception of the soundfield as a real space as well.

Lastly, no matter what I try, I can never get the same sensation of sound behind me on the stereophile CD in the livelier room; the room cues are just too strong telling me the sound is coming from the front to let the perception of sound behind me materialize. It's not just the speakers, the room and setup matters, too.

There are many recording can create sound behind you using effects. This sound is typically for short duration or just fleeting as the illusion can only lasts for few seconds before the brain localize the actual air action of the sound coming. Even with XTC, I cannot claim that I could make the bee flying binaural recordings going behind my head although it can happen for fleeting seconds and not too far behind the head.

 

[STC]

This is a very good question. In stereo recordings we get ITD and ILD information and that is how we perceive panning of the stereo imaging.

To perceive elevation of sound source we use pinnae, that is, we process how our outer ear modifies the spectrum of the sound and this is how we get yet another, spectral shape cue. I have no idea how this works, or how to pinpoint the exact speaker design, setup, or room characteristic that makes this happen. On my system there are plenty of recordings which sound way higher than the loudspeakers are. I'm just guessing it has something to do with room acoustics. But what you hear may be very different from what I hear.

Stereo got no height information. It is normal for height illusion to be created such as LEDR test using frequency manipulation. And as tweeter are typical placed higher than the woofer some may perceive birds chirping to be coming from above. Interestingly, I have a recordings made from the balcony where the birds were chirping on the floor yet when played through the speakers some still localize the birds as coming from the top. I guess they expect birds to flying and imagination started to fill in to make sense to the sound they hear.

 

[STC]

have a binaural recording that features airplanes flying overhead. Those seem to go right over me, and it works on just about every stereo system I've tried it with.

that because you already knew that airplanes will fly above your head. The brain’s job is to decode the sound and make it useful information and often create the scene based on prior knowledge or experiment.

 

[NIN]

I hear in so many tracks capable of doing that. And there are special effects ( DSP) to do just that. I can do it even with recordings without any effects by adding the effects during playback.

Well, you said "If conventional stereo could do all these things you are saying than I am yet to see such system.".
And clearly one can get a soundstage, with stereo speakers, that are outside of the speakers.

 

[STC]

Well, you said "If conventional stereo could do all these things you are saying than I am yet to see such system.".
And clearly one can get a soundstage, with stereo speakers, that are outside of the speakers.

Unless you made the recordings, you don’t know whether they were processed with width expansion effects. A microphone functions the same whether in your hands or a professional. A professional can produce better quality recordings because the know where and how to place them. But that will not change the ILD or ITD ( if any) .

Toole’s book is useful.

 

[NIN]

A further question if I may (not sure if this one has been asked already), is soundstage something baked into the recording, which speakers can reproduce more or less accurately? Obviously a soundstage that give the audible impression of a 7ft tall girl and guitar may be impressive, but it hardly like to be accurate (unless it is a Dutch girl, perhaps). How do we know whether a soundstage is, more or less, accurate or is it purely a question of taste?

I would say that a system (speakers and room) that give the biggest difference in soundstage between different music is probably more accurate than a system that sound alike.

 

[NIN]

Unless you made the recordings, you don’t know whether they were processed with width expansion effects. A microphone functions the same whether in your hands or a professional. A professional can produce better quality recordings because the know where and how to place them. But that will not change the ILD or ITD ( if any) .

Toole’s book is useful.

Off course it is done with effects.

 

[NIN]

I posted it earlier but try “Two Weeks” by FKA twigs. The song isn’t great but there is a staccato effect that begins around 51 secs that sounds well above the rest of the soundstage on my speakers. It’s the only stereo recording that I’ve heard any sort of “height” in.

Start around 0:35

 

[Bugal1998]

That is incorrect because pinna’s role is to externalize sound. Unless you do not have pinna ( outer ear) you will hear the sound outside you head because pinna functions as a direction finding mechanism.

You are mistaken on this point. The effect I experienced has also been documented by respected researchers.

I also have headphones that strongly engage the pinna, and I suspect that is why they have such a spacious experience that can extend well outside the head. But the centered sounds still exist squarely inside the head, which by your theory of the pinna shouldn't be possible.

Unless the stereo mics is spaced around 17 cm, the ITD information is wrong. XY configuration mics do not have ITD at all.

Agreed. And there are additional options beyond simple spacing of the L/R mics. We could probably debate whether the sense of space, width, etc. is correct when played back (I personally doubt it's correct) but correctness isn't the criteria here, merely the existence of width, space, etc.

There many recording can crate sound behind you using effect.

I'm confused, using what effect?

This sound is typically short duration or just flashes as the illusion can only lasts for few seconds before the brain localize the actual air action of the sound coming.

I'll have to disagree on this point. In the example I referenced it persisted long enough for the person to walk from the back of the church to the front, and I could (and did!) play it over-and-over back-to-back to repeatedly experience the effect, and it never once faded until I changed the room acoustics.

Even now there are songs that have persistent reverb that appears behind my head for the entire song.

Even with XTC, I cannot claim that I could make the bee flying binaural recordings going behind my head although it can happen for a fleeting seconds and not too far behind the head.

Agreed that with very few exceptions the sound is not very far behind the head. Make no mistake, there are very significant limits on what 2-channel can produce by way of sensations behind the head. But that's entirely different than saying it can't be done, except with special digital processing, which is how I interpreted you prior posts.

The topic is soundstage of stereo and whether speakers can improve that. What I am reading so far there is confusion with sound stage, imaging and spaciousness.

Agreed. I don’t believe speakers can improve soundstage, though certain poorly engineered speakers can erode the effect. Speaker dispersion, room acoustics, system setup all factor into the final experience.

And agreed on the confusion; I know I've been referencing all three.

Anyway, you have strongly held beliefs on the matter that contradict my personal experiences, and your beliefs will no more convince me that I haven't experienced these acoustic sensations than my personal anecdotes will cause you to question your beliefs. And that's OK, so I'm just as happy to leave these discussions where they are.

Best!

 

[Tim Link]

that because you already knew that airplanes will fly above your head. The brain’s job is to decode the sound and make it useful information and often create the scene based on prior knowledge or experiment.

Maybe. I think it might be because the dummy head microphone they used matches my HRTF close enough to simulate overhead sounds in a convincing way.

 

[Axo1989]

I posted it earlier but try “Two Weeks” by FKA twigs. The song isn’t great but there is a staccato effect that begins around 51 secs that sounds well above the rest of the soundstage on my speakers. It’s the only stereo recording that I’ve heard any sort of “height” in.

No no no. The song is great. After that, how can I believe anything you say?

Edit: tangential to the thread, but I was super-interested a while back to see a live version where (almost, there's a backing track I assume) all the sounds are played/triggered by drumsticks on various percussion pads. Sounds a bit different to the LP1 album version so who knows how that was done, but on the latter yes, I also get the above-the-general-mix impression at that point/effect in the track. A few of her tracks do interesting soundstage-y things I reckon, Figure 8 is one of my standard test tracks.

Spoiler: Two Weeks on KEFP

 

[Axo1989]

Exactly. Our hearing evolved for survival not fill in our imagination. Music supposed to do that.

That is incorrect because pinna’s role is to externalize sound. Unless you do not have pinna ( outer ear) you will hear the sound outside you head because pinna functions as a direction finding mechanism.

Space is capture or conveyed with the amount of reverberations. Unless the stereo mics is spaced around 17 cm, the ITD information is wrong. XY configuration mics do not have ITD at all.

Nothing wrong with that. The topic is soundstage of stereo and whether speakers can improve that. What I am reading so far there is confusion with sound stage, imaging and spaciousness.

I have a SACD of piano recordings made by different mics. And one started to talk about the correct sound of piano and what not I use them for them to explain the difference.

There many recording can crate sound behind you using effect. This sound is typically short duration or just flashes as the illusion can only lasts for few seconds before the brain localize the actual air action of the sound coming. Even with XTC, I cannot claim that I could make the bee flying binaural recordings going behind my head although it can happen for a fleeting seconds and not too far behind the head.

I think there's a semantic issue where you may be specifying 'stereo' to mean certain microphone techniques/recordings but classifying 'effects' as something extra, or not-stereo. I can make more sense of your posts taking that into account, but it seems to me to be an idiosyncratic and limited definition of stereo.

 

[STC]

Maybe. I think it might be because the dummy head microphone they used matches my HRTF close enough to simulate overhead sounds in a convincing way.

So your stereo could produce height? But scholars think otherwise.

 

[STC]

I think there's a semantic issue where you may be specifying 'stereo' to mean certain microphone techniques/recordings but classifying 'effects' as something extra, or not-stereo. I can make more sense of your posts taking that into account, but it seems to me to be an idiosyncratic and limited definition of stereo.

Special effects have been used to create something extra where ordinary stereo recordings cannot reproduce. Almost all best seller records always had something different from their typical stereo recordings. We get attracted to sound that are unique and defy expectation.

 

[BenB]

To be fair the link, while interesting is not a definition. A definition is something short enough to fit in a dictionary and describes what soundstage is (and perhaps, is not). Let me make a rough attempt at a definition:

Soundstage is the effect of hearing (perceiving?) a different 3D space to your own, presented in your room through loudspeakers. The effect is mainly referring to playback through stereo systems, and can also be appreciated over multi-channel surround systems, but is absent in mono (you need at least two speakers to create a 'soundstage'). Soundstage is present in a recording through phase and timing relationships of audio signals as they appear at microphones, when instruments are recorded, or can be created/synthesized by manipulation when dealing with purely electronic sources.

This is my (very rough) attempt at a definition. A definition should be able to fit in a dictionary and make sense of what a soundstage is (and perhaps, is not).

The reason I ask for a definition is because if the thing exists, it should be defined (and easily definable), so that people don't end up talking at cross purposes about different things that they believe are 'soundstage', but perhaps aren't. If it is a thing, it should be able to be explained a relatively comprehensive, yet concise definition.

Anywaaaay, back to the topic in hand. I have to say I haven't heard 'soundstage' anywhere near as much as some others have (things inside their heads, behind the front wall and so on), this may be because I listen to mainly electronic music and old classical music, where the quality of the recordings are rather lacking to even consider soundstage much or that my setup is not as optimised as some.

The most lifelike (in that sounds seemed most similar to unreproduced/real sounds) audio reproduction I've heard through a stereo system has been from a recording using an Ambisonic Soundfield microphone. Seeing as those are set up to provide phase coherence, that seems to somewhat translate even through a stereo system, I can only surmise that phase is very important to perceiving a sound as real, rather than reproduced.

I have not had as convincing a 'soundstage' experience with pan-potted, multi-mic stereo recordings. It seems to me that whatever the Soundfield microphone is doing, it represents something far closer to an audio event (as it occurs at one particular point in space), than anything pan-potted stereo does....

is this a digression...I don't know, but it does strike me as interesting.

Regarding the panpot, see this thread for a bit of analysis in its application to stereo speakers: https://www.audiosciencereview.com/forum/index.php?threads/in-defense-of-the-panpot.48634/

 

[Axo1989]

Special effects have been used to create something extra where ordinary stereo recordings cannot reproduce. Almost all best seller records always had something different from their typical stereo recordings. We get attracted to sound that are unique and defy expectation.

Your "something extra" vs "ordinary stereo" is a distinction without a difference wrt modern stereo production. What you posit as "ordinary" is now the exception. In other words, your semantics probably had some weight decades ago, but we can dismiss those observations and conclusions viz. what stereo "can or can't do" in this discussion as anachronistic.