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Why does mono listened to from a stereo pair have a sense of height and depth?

srrxr71

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So this may apply to also a single mono speaker but I have not tried it.

When I switch the signal from stereo to mono on any song I get a solid center image of the mono presentation.

This mono image still has good separation of instruments. In fact it provides height and depth information to my ears and brain. This seems like part of the separation thing where since they don’t all sound coincidently where maybe my brain is imputing that one instrument is behind another due to level differences.

Also some instruments seem to be above or below others.

Is this information in the recording?
 

Doodski

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So this may apply to also a single mono speaker but I have not tried it.

When I switch the signal from stereo to mono on any song I get a solid center image of the mono presentation.

This mono image still has good separation of instruments. In fact it provides height and depth information to my ears and brain. This seems like part of the separation thing where since they don’t all sound coincidently where maybe my brain is imputing that one instrument is behind another due to level differences.

Also some instruments seem to be above or below others.

Is this information in the recording?
Partially in the recording and partially the room's response too.
 

Chrispy

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I'd try the mono speaker thing first.
 

tomelex

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One instrument louder than another gives you depth, separation of tweeter and bass speakers within the speaker give you height according also to their beam patterns and reflections from your room and the height of your ears from the floor.

Turn the speakers upside down (on their head) and notice the height sensation changes.

Mono does one thing, it gets rid of the weird "stereo" affects that your brain has gotten used to interpreting and that takes work/energy.

Keep running mono for a few days or so then when you listen to your first stereo recording it will sound very contrived to you, but the brain soon adapts back to that sound, probably after only 4 or 5 songs since you have almost 100% grown up on stereo.
 
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srrxr71

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Partially in the recording and partially the room's response too.
Yes this makes sense as each speaker will have some phase shift induced by its own local environment and the path to your ear.

I’ve got the room treated decently but I’ll try again after the ceiling gets some treatment.

I suspect it will get tighter in terms of image.

Also it’s clear to me this effect also affects the perception of the center image of a stereo recording.
 

Tangband

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So this may apply to also a single mono speaker but I have not tried it.

When I switch the signal from stereo to mono on any song I get a solid center image of the mono presentation.

This mono image still has good separation of instruments. In fact it provides height and depth information to my ears and brain. This seems like part of the separation thing where since they don’t all sound coincidently where maybe my brain is imputing that one instrument is behind another due to level differences.

Also some instruments seem to be above or below others.

Is this information in the recording?
You should experimenting more with that mono signal - put only one of your speakers in the middle of the loudspeaker sweet spot and fine out If there is any difference compared with two mono speakers with some space apart.
You might be surprised. With two loudspeakers and a mono signal , you get some attenuation at 1,8 kHz , depending on the space between your ears.

The stereo illusion effect in your brain at playback, depends on the space between your ears, and the reflections from walls in the listening room. With only one ear, theres no stereo. Draw conclusion from this - and maybe make your own recordings to find out more.

The perceived soundstage with two channel recording and playback with two stereo speakers ( or two mono ) in a room is only an illusion of the real recorded event . Its nowhere near the sound from the concert hall.
 
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srrxr71

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One instrument louder than another gives you depth, separation of tweeter and bass speakers within the speaker give you height according also to their beam patterns and reflections from your room and the height of your ears from the floor.

Turn the speakers upside down (on their head) and notice the height sensation changes.

Mono does one thing, it gets rid of the weird "stereo" affects that your brain has gotten used to interpreting and that takes work/energy.

Keep running mono for a few days or so then when you listen to your first stereo recording it will sound very contrived to you, but the brain soon adapts back to that sound, probably after only 4 or 5 songs since you have almost 100% grown up on stereo.
That’s an interesting point about the work/energy involved in listening to stereo. It’s true it is a sense of work.

However I feel like that as I upgraded my system some systems allow for less work and the center image is solid without much if any thought.


I wonder if treat the reflection points on the ceiling and the floor would the sensation of height disappear assuming i’m using a point source radiator?
 
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srrxr71

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You should experimenting more with that mono signal - put only one of your speakers in the middle of the loudspeaker sweet spot and fine out If there is any difference compared with two mono speakers with some space apart.
You might be surprised. With two loudspeakers and a mono signal , you get some attenuation at 1,8 kHz , depending on the space between your ears.

The stereo illusion effect in your brain at playback, depends on the space between your ears, and the reflections from walls in the listening room. With only one ear, theres no stereo. Draw conclusion from this - and maybe make your own recordings to find out more.

The perceived soundstage with two channel recording and playback with two stereo speakers ( or two mono ) in a room is only an illusion of the real recorded event . Its nowhere near the sound from the concert hall.
I tried a few experiments. It seems like the phantom mono image is wider. I suppose I could toe in the speakers to tighten it up.

Otherwise it’s slightly louder and mostly the same.

This experiment did help me toe in one speaker a bit more.


Edit: Also I discovered that one of my favorite music video songs on YouTube is actually a mono recording. Sounds the same whether the switch is on mono or stereo.
 
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BJL

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I have many recordings with original mono mixes. I listen to them through a single speaker, the center speaker. I find that the sound blooms outward. I've tried playing back mono through the stereo (L/R) pair, and I don't like it. To me, the music collapses to the center, instead of blooming outward into the room and it sounds too loud. Also, I suspect that there are some odd out of phase effects from the two speakers interacting because the music doesn't always have that pure mono sound. I haven't listened to any stereo recordings folded down to mono. This would seem to me to be contrary to the artist's intent.

If you have the option, I'd suggest playing back mono audio through your center channel speaker (if you have one).
 

tomelex

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That’s an interesting point about the work/energy involved in listening to stereo. It’s true it is a sense of work.

However I feel like that as I upgraded my system some systems allow for less work and the center image is solid without much if any thought.


I wonder if treat the reflection points on the ceiling and the floor would the sensation of height disappear assuming i’m using a point source radiator?

Although through the tricks of stereo you can deliberately encode height information, in mono as I mentioned it is the speakers and the room, and if you treat the room reflections correctly the very little sense of height you may now hear can certainly be suppressed.

The center image is solid with stereo without much effort, but when you listen closely you can hear for example a guitar that is mostly in the right channel but also put in the left channel very slightly and possibly delayed to create an echo effect, and then your brain has to start working harder, which you may or may not notice.
 
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srrxr71

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Although through the tricks of stereo you can deliberately encode height information, in mono as I mentioned it is the speakers and the room, and if you treat the room reflections correctly the very little sense of height you may now hear can certainly be suppressed.

The center image is solid with stereo without much effort, but when you listen closely you can hear for example a guitar that is mostly in the right channel but also put in the left channel very slightly and possibly delayed to create an echo effect, and then your brain has to start working harder, which you may or may not notice.

Sure that sensation of height has to be caused by local phase shifts. I will dial out a lot of it when ceiling panels are installed.

As for the recording and echo could we argue it’s the same at a performance or there is something different about how stereo fakes it?

I suppose all listening to some degree involves using subconscious brain power.

We can evolved with our ears to detect threats and so we don’t use that system all the time at least these day. I suppose people of the past may have had large periods of having to use their ears.

Today we have the luxury of willingly going to performances of music to use our auditory systems for hours. Alternatively playing music on our systems to do something similar.

For me in general upgrading my system has cut down the “listen closer” impulse a lot.

When I started this hobby it was crazy. I’d spend money get the product home and listen intently. It was stupid in hindsight. More of a hunt to find justification for the expenditure.

There was so much mental noise. Maybe I could call it the meta nonsense. The story of how I heard and then acquired the speaker/amp/cable/turntable. The psych up of the designer’s qualifications, their marketing junk and the mental masturbation of reading the reviews.

So much mental energy spent into listening “hard”.

Now I don’t bother. Either it’s there and apparent or I don’t bother. Some songs still with a highly resolving system do invite you to listen harder. But it’s easier to follow the different tracks in the mix. Sometimes you have to expend some energy.

Overall though the upgrade was worth it primarily for the reason you brought up. The amount of energy I use while listening is far less than before. Maybe not as low as going to a live performance but roughly about there. Very rarely do I care to listen with concentration anymore. There’s just so much to catch without expending that kind of energy.

I’ve come to learn that’s the highest goal of improving your system. So you can listen and enjoy with the least amount of energy expenditure.


Edit: One other thing I noticed is that the audiophile will go into reading about the equipment. The musician type will start reading about the musicians and their backstory. This tells me something is wrong.

If the waves hitting your ears aren’t moving you enough to not have to read then something is wrong. If you read more than you listen then something is wrong. Just a simple litmus test of whether your system is working for you or you are working for it.

That’s a difficult trap for all of us to avoid. All of is discussing equipment and science here is great. What proportion of my time is spent here vs actually listening?
 
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Cbdb2

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If you line up a few sound sources (instruments, voices), one behind the other, all right in front of you do hear depth? You do but it obviously has nothing to do with LR dfferences. Depth is in the reverb/reflections. The ratio of direct to reflected sound. Its in the FR. Sources further away have less high freqs. Closer sources are more dynamic, again to do with the reverb. Closer sources have more "detail". You can hear the keys hit on a saxophone or the lip smacks on a vocal. One thing thats hard to change once recorded.

I recorded ADR for movies for years. Which is replacing or adding lines, often in the middle of a scene. So the object is to make it sound identical to the dialogue around it, not as easy as it sounds. (and not easy for the actors, they have to be in sync with the picture as well as acting, unless your Ann Margaret doing her lines while crying, I was blown away.) The mixer can adjust a lot of the sound to match but the hardest thing to change is someone recorded to close to the mic.
 

kemmler3D

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A good question, for your answer you can look up "how to fake height and depth while mixing"... many tutorials out there for producers / engineers to create this effect. In fact there are some plugins specifically made for this. :)

Basically height can be simulated in mono using certain EQ and amplitude tricks, depth is simulated by EQ, volume, short delays relative to other channels in the mix, and how much reverb you mix in. Depending on the quality of the reverb and how well you mix, it is more or less convincing. It can be done by hand in any DAW pretty easily as long as you know what you're doing beyond sheer beginner status.

Stereo helps with reverb being convincing, but is not necessary.

These signals are also preserved in real mono recordings. Basically stereo mostly (almost only) helps you with left/right positioning, you can still do up/down front/back without it, although it may be less convincing.
 
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