A Broad Discussion of Speakers with Major Audio Luminaries

[MaxwellsEq]

Hi @Artsfols what you are not grasping is that a single pressure change in your eardrum is what you hear. Don't get sidetracked into headphones, binaural, multi-speaker environment. Focus exclusively on, say, your left ear.

A trombone and violin are playing different tunes near your left ear. It's a complicated swirl of notes and volume changes. Your ear can't detect that complexity. Instead pressure waves impinge on your eardrum. These pressure changes are the SUM of the two tunes. You do NOT experience the pressure changes from the two instruments separately - there is simply a single, complex, fast changing SINGULAR pressure wave. Add 30 instruments, still only one, combined pressure wave (not 32). Add a cannon, still only one complex pressure wave, but for a few milliseconds, the pressure wave from the cannon dominates.

 

[Heinrich]

Hi @Artsfols what you are not grasping is that a single pressure change in your eardrum is what you hear. Don't get sidetracked into headphones, binaural, multi-speaker environment. Focus exclusively on, say, your left ear.

A trombone and violin are playing different tunes near your left ear. It's a complicated swirl of notes and volume changes. Your ear can't detect that complexity. Instead pressure waves impinge on your eardrum. These pressure changes are the SUM of the two tunes. You do NOT experience the pressure changes from the two instruments separately - there is simply a single, complex, fast changing SINGULAR pressure wave. Add 30 instruments, still only one, combined pressure wave (not 32). Add a cannon, still only one complex pressure wave, but for a few milliseconds, the pressure wave from the cannon dominates.

@MaxwellsEq. "tl;dr" (to long; didn't read). When I was told what that meme means I was LoL.

Your explanation isn't to long, but it needs a vast amount of background knowledge to be acceptable for a first-time reader. People are going to ask what something like "human hearing is capable of discriminating tunes down to 0.5% of a frequency" is based on. In order to save the conversation you would need to explain the perception of sound by the ear in more detail. But originally it was a question about the properties of the speaker, its "fast-ness". So we would keep on spiralling on and on, posts getting longer and complicated.

What I see in modern society, no offense, really, is a disconnect of tech minded, knowledgable specialists versus consumers. No offense, I'm a complete layman when it comes to pharmaceutics to pick just one field.

Every day culture would under normal circumstances reconnect the two. It would invent behavioral patterns, based on trust, that would allow to use stuff without a deeper understanding. But in audio this evolving process is deliberately disrupted by fraudulent advertizing, fulls stop.

 

[pablolie]

..
A trombone and violin are playing different tunes near your left ear. It's a complicated swirl of notes and volume changes. Your ear can't detect that complexity. ...

My ears know exactly which notes the different instruments play. At no point in time in "Waltz for Debbie" as an example) am I ever in doubt about the difference between piano, bass and drums. And in a good classical recording, it's easy to identify the positioning of the entire orchestra (who plays what) and -if there- the soloist. I disagree things get compressed and convoluted -as you seem to try to say- because the frequencies are multiplexed. Both in tech and in the human ear they can be "de-multiplexed" when/if it matters, easily.

 

[NTK]

Who is the manufacturer that sells a system / signal processor with “cross-talk cancelled loudspeaker version”?
You got me curious. What should I buy to experience this? I have Revel Performa f206, if it is relevant..

The overwhelming favorite here is BACCH. Here are two of the threads on BACCH and the main distributor of the BACCH technology Theoretica Applied Physics' website.

BACCH4MAC Short Review / first impressions

So I finally broke the bank and purchased the Intro version of BACCH-DSP 4 MAC (V12.2). Introduction My experience is, that the interaction between room and speakers has by far the greatest impact on how I enjoy music listening. Most of my upgrades of the last 10 years went into room acoustics...

www.audiosciencereview.com

Dr. Edgar Choueiri explains BACCH

How does BACCH enhance the spatial realism in the reproduction of acoustical recordings made in real acoustical environments? Crosstalk cancellation (XTC) techniques, such as BACCH, suppress the sound recorded on the left (right) channel of a stereo recording at the right (left) ear of the...

www.audiosciencereview.com

Theoretica Applied Physics

Bringing 3D audio from the laboratory to the real world.

www.theoretica.us

Dutch & Dutch offers a BACCH plugin for their 8c.

Dutch&Dutch add ‘uBacch’ to their 8C active loudspeaker

The next thrilling instalment of Purité Audio’s unmissable new BLOG! https://www.puriteaudio.co.uk/blog-purite-audio-retailer-london Keith

www.audiosciencereview.com

BACCH plugin

Bring the groundbreaking BACCH 3D spatial audio technology to your 8c's, through the first third party software plugin for a loudspeaker ever. Note: Requires firmware r2.4 or later. Works only with direct streaming. More information on BACCH here.

dutchdutch.com

There are other much "less sophisticated" implementations such as Polk's SDA.

Stereo, Supersized: Inside Polk SDA Technology | Polklore

Try this little experiment: Close our eyes and listen to the sounds around you. Notice how you can easily tell where sounds are coming from, even when you can’t see them?

www.polkaudio.com

 

[Jim Taylor]

What I see in modern society, no offense, really, is a disconnect of tech minded, knowledgable specialists versus consumers.

I see consumers as being desirous of the benefits of modern technology. I don't blame them; I'm in the same boat. But our society has become so complicated in the last 50-60 years that the vast majority of people on the street can barely keep up. The days of graduating University and resting on your laurels for the remainder of your career are long gone. And what with the societal changes and rapid changes in people's personal lives, the technological changes, by default, get short shrift.

IMO, that is the cause of the disconnect you've mentioned. Yes, it's real, and yes, we wish fervently that it were not so. THE BEST WE CAN DO IS TO BRING OUR RESOURCES TO BEAR ON EVERY INDIVIDUAL WE MEET.

That's the compassionate way, but it's also the way that most obviously benefits us. Otherwise, we'll eventually end up like Dr. Frankenstein ... the target of the angry mob. There are indications around us every day that the mood of the populace is gradually going that way; more and more people are showing a mistrust of science and logic.

The higher we've climbed the ladder, the more it's in danger of being kicked out from under us. That's not a good situation.

 

[MaxwellsEq]

@MaxwellsEq. "tl;dr" (to long; didn't read). When I was told what that meme means I was LoL.

Your explanation isn't to long, but it needs a vast amount of background knowledge to be acceptable for a first-time reader. People are going to ask what something like "human hearing is capable of discriminating tunes down to 0.5% of a frequency" is based on. In order to save the conversation you would need to explain the perception of sound by the ear in more detail. But originally it was a question about the properties of the speaker, its "fast-ness". So we would keep on spiralling on and on, posts getting longer and complicated.

What I see in modern society, no offense, really, is a disconnect of tech minded, knowledgable specialists versus consumers. No offense, I'm a complete layman when it comes to pharmaceutics to pick just one field.

Every day culture would under normal circumstances reconnect the two. It would invent behavioral patterns, based on trust, that would allow to use stuff without a deeper understanding. But in audio this evolving process is deliberately disrupted by fraudulent advertizing, fulls stop.

Thank you.

 

[MaxwellsEq]

My ears know exactly which notes the different instruments play

Your ear experiences pressure. Your brain interprets it as music.

 

[Artsfols]

That's not correct way to look at it. If you are playing a cord on the Piano, all the notes combine into a composite waveform that the microphone picks up to record. Neither the microphone, nor the recorder know anything about its frequency make up. As long as they both have ample bandwidth, they record the totality of what is in that cord. Same happens at playback. The whole system is just varying voltages.

Now, when you hear it, or when we want to analyze the sound, we decompose the time domain, voltage varying signal into frequency components. But neither microphone, nor speaker are operating that way. If the signal is a mix of low and high frequencies, the high frequencies show up as small variations on the low frequency waveform (assuming the high frequencies are lower amplitude).

As an example, look at this 32-tone signal in frequency domain:

This is what it looks like to a microphone or speaker:

Speaker and microphone simply move their cones proportional to this latter waveform, oblivious to the fact that it is made up of 32 distinct tones.

First of all, super cool diagrams to see that visualized.
But, I already understand some of what you're saying, although I lack some of the terminology.
I mean, I understand that we are dealing with a waveform that can be represented in 2D in time domain
and that contains all the information to be able to reproduce any potential combination of frequencies.
I have some questions.
In time domain, I believe I see a complex wave that is not repeating, so it takes 200 ms to emit all the information to produce those 20 tones.
1) Is that correct?
2) Is that effectively instantaneous to the ear?
3) Is the amount of time, say it is 200 ms, some kind of a constant, or is it derived from the complexity of the frequency spectrum?
4) If you sustained the 32 tone signal for say 1 minute, would you see the time domain signal repeat ever so many ms?
And my most basic question has always been, is there a combination of tone signals, or source sounds, that begin to present
a problem for the speaker.
I realize it's just responding to a linear stream of voltage signals, but it IS a physical cone that must have physical limitations.

 

[pablolie]

Your ear experiences pressure. Your brain interprets it as music.

oversimplification. following that reasoning we are just oversized amoebas :-D

 

[MaxwellsEq]

oversimplification. following that reasoning we are just oversized amoebas :-D

Your brain is the part of your body that interprets the pressure wave captured by your eardrum. It makes sense of it all, including deciding something is a trombone and something else is a violin, based on the training it receives as you grow up.

Music and the brain: the neuroscience of music and musical appreciation - PMC

Through music we can learn much about our human origins and the human brain. Music is a potential method of therapy and a means of accessing and stimulating specific cerebral circuits. There is also an association between musical creativity and ...

pmc.ncbi.nlm.nih.gov

Thus, lesions following cerebral damage lead to impairments of appreciation of pitch, timbre and rhythm

 

[Artsfols]

I’m curious about what, if anything at all, frequency response leaves out in telling us how loudspeaker will sound.

As I understand you’ve written that most things that matter will show up in the frequency response - including driver or cabinet colorations due to resonances (please correct me if I’m wrong).

I know there’s of course off axis measurements, and similarly neutral speakers can have different dispersion patterns which can cause them to sound different depending on the room and set up. But that’s still essentially about frequency response.

So my question is, what of importance does frequency response leave out, if anything?

So two scenarios:

1. If you were comparing (blind) loudspeaker A and B, and loudspeaker A seems to be revealing slightly more Sonic detail, for instance very subtle recorded room acoustics or very subtle artificial reverb is revealed on speaker A, would the explanation of that difference likely be spotted in the frequency response of each speaker? Or is it possible for two speakers to measure essentially neutral, but one has a slightly livelier cabinet, or the other design has gone to heroic measures to make a completely inert cabinet. Is it possible that Sonic advantages from a more inert cabinet might reveal the type of subtle details I’m talking about, and this factor would not show up in or be obvious from evaluating just the frequency response of the two speakers? Or will any such audible difference at all in the designs be captured in the frequency response?

I guess another way of putting it: as long as you have a flat frequency response, will that assure the speaker is producing all the recorded detail un-obscured, and no other parameter of the design would affect this?

2. There’s been occasional discussions about the perceptual effects of larger speakers and larger drivers versus smaller speakers and smaller drivers. The idea of being that there is something about a truly big speaker that can give a sense of larger scale versus a smaller speaker, even if they both have the same frequency response specifications.

So as a thought experiment: let’s say we had A super Duper Speaker comparator system for blind testing they could accommodate any size speaker. And let’s say we have some “ pick your neutral” stand mounted monitor (say a good Genelec monitor) combined with a subwoofer or two, and we’ve got those measuring with flat frequency response from 20 Hz to 20 K.

On the other hand, we have a huge PA system, of the type you might find in a very large club, and this system has also been made flat from 20 Hz to 20 K.

So in terms of strict frequency response, they are essentially the same. And we play them back at the same sound levels.

And yet, at least intuitively, I think we’d expect that even playing at something like an 85 DB level, the systems would sound different, the scale of the PA system sounding significantly more grand. And probably more convincing in various ways for instance recreating an orchestra, etc.

Is there anything wrong with these intuitions?

And if not, what would count for the Sonic differences between these two systems that have the same frequency response played at the same volume levels? Is it something to do with the sheer amount of air being moved by the larger system? Or is that not even a factor if we’re talking about the same levels and the same frequency response?

(Thanks to anybody else who wants to chime in on this).

From what we've been hearing if you had two speaker systems, one tiny and one very large, that both had a flat and full spectrum frequency response, and placed them in an anechoic chamber, they would sound identical. You could not tell them apart.
I hope you get an expert answer though; I'd be interesting in reading it.
And then, in reality, speakers always act in real world conditions so that much more comes into play than just obtaining a flat frequency response. I have a relatively small listening room, so I don't want big speakers, for example.

 

[pablolie]

Your brain is the part of your body that interprets the pressure wave captured by your eardrum. It makes sense of it all, including deciding something is a trombone and something else is a violin, based on the training it receives as you grow up.

are u writing a tutorial for 4 year olds? :-D

hoping a moderator brings this back on topic.

 

[MaxwellsEq]

are u writing a tutorial for 4 year olds? :-D

Apparently.

 

[pablolie]

Apparently.

obviously. your knowledge on the matter doesn't extend beyond.

 

[Artsfols]

The deviations in response of speaker either manifest themselves in linear changes in frequency response, or non-linear changes due to distortion. Neither is characterized by slow or fastness of anything. You can have a lousy 15 inch woofer that produces far more distortion playing 50 Hz than a small one that is more linear. Speed/velocity are not terminology we use here to describe the artifacts. In my tests, I show both frequency response and distortion so what you worry about, is covered in the measurements.

I have dropped the idea of 'velocity' entirely. I did not know this was an audiophile thing either, because I don't read or watch qualitative reviews. I'm not really interested in them.
Any concept I had of velocity never had anything to do with the speed of the cone, as it was taken, but I was thinking purely of the responsiveness of a cone, or lack thereof, to an input signal. But that would just be distortion in terms of your measurements.
Perhaps I should be reading a primer on audio measurements, if there is such a thing. If not, you could make one from all your posts here.
Anyway, the underlying question then becomes one of the relationship of distortion to source material, versus distortion due purely to cone failings or cabinet resonances, et cetera.

 

[MaxwellsEq]

obviously. your knowledge on the matter doesn't extend beyond.

Music and the brain: the neuroscience of music and musical appreciation - PMC

Through music we can learn much about our human origins and the human brain. Music is a potential method of therapy and a means of accessing and stimulating specific cerebral circuits. There is also an association between musical creativity and ...

pmc.ncbi.nlm.nih.gov

Thus, lesions following cerebral damage lead to impairments of appreciation of pitch, timbre and rhythm

 

[Artsfols]

Hi @Artsfols what you are not grasping is that a single pressure change in your eardrum is what you hear. Don't get sidetracked into headphones, binaural, multi-speaker environment. Focus exclusively on, say, your left ear.

A trombone and violin are playing different tunes near your left ear. It's a complicated swirl of notes and volume changes. Your ear can't detect that complexity. Instead pressure waves impinge on your eardrum. These pressure changes are the SUM of the two tunes. You do NOT experience the pressure changes from the two instruments separately - there is simply a single, complex, fast changing SINGULAR pressure wave. Add 30 instruments, still only one, combined pressure wave (not 32). Add a cannon, still only one complex pressure wave, but for a few milliseconds, the pressure wave from the cannon dominates.

I understand that. But do you understand that the cochlea then decodes that single wave into frequency components and passes that to the brain?

Physiology, Cochlear Function - PubMed

The cochlea is a fluid-filled, spiral-shaped cavity found in the inner ear that plays a vital role in the sense of hearing and participates in the process of auditory transduction. Sound waves are transduced into electrical impulses that the brain can interpret as individual sound frequencies...

pubmed.ncbi.nlm.nih.gov

 

[MaxwellsEq]

I understand that. But do you understand that the cochlea then decodes that single wave into frequency components and passes that to the brain?

Physiology, Cochlear Function - PubMed

The cochlea is a fluid-filled, spiral-shaped cavity found in the inner ear that plays a vital role in the sense of hearing and participates in the process of auditory transduction. Sound waves are transduced into electrical impulses that the brain can interpret as individual sound frequencies...

pubmed.ncbi.nlm.nih.gov

That's correct.

 

[Artsfols]

I see consumers as being desirous of the benefits of modern technology. I don't blame them; I'm in the same boat. But our society has become so complicated in the last 50-60 years that the vast majority of people on the street can barely keep up. The days of graduating University and resting on your laurels for the remainder of your career are long gone. And what with the societal changes and rapid changes in people's personal lives, the technological changes, by default, get short shrift.

IMO, that is the cause of the disconnect you've mentioned. Yes, it's real, and yes, we wish fervently that it were not so. THE BEST WE CAN DO IS TO BRING OUR RESOURCES TO BEAR ON EVERY INDIVIDUAL WE MEET.

That's the compassionate way, but it's also the way that most obviously benefits us. Otherwise, we'll eventually end up like Dr. Frankenstein ... the target of the angry mob. There are indications around us every day that the mood of the populace is gradually going that way; more and more people are showing a mistrust of science and logic.

The higher we've climbed the ladder, the more it's in danger of being kicked out from under us. That's not a good situation.

No one can be expert in all areas. I'm an expert in computer software and especially ERP software, not just implementation, but I have been designing ERP software for 50+ years; and at one time I also programmed them.
Anyway, we rely on people to mediate these decisions for us. It's interesting for me to be in the position of the person asking the "dumb questions" when often I am the person dealing with them, in my field. It's really important, in part, because me making money depends on it, to make people, my customers and their employees, feel comfortable talking to us when they have an issue. A big part of it is to down shift from the terminology we as developers use daily to get our jobs done, to communicate with customers when they have an issue, say, or are making a request. Many programmers just can't do it.
I do have a sense that "trust" is going out the window these days. Various reasons for that. People develop positions and opinions without having the backup to take a fixed position. This is what most annoys me, not in my profession, but in general. No one wants to say that they don't know something. Perhaps it is all the buttering up and emphasis on self-worth in recent decades that has caused this.
And I'm sure this is true in the audio area as well. Strong opinions without backup. I hope it is clear that I am venturing provisional views more as a journey toward understanding. No one is obligated to respond, so I'm pleased with the responses I have received which cleared up some areas for me.

 

[Floyd Toole]

The overwhelming favorite here is BACCH. Here are two of the threads on BACCH and the main distributor of the BACCH technology Theoretica Applied Physics' website.

BACCH4MAC Short Review / first impressions

So I finally broke the bank and purchased the Intro version of BACCH-DSP 4 MAC (V12.2). Introduction My experience is, that the interaction between room and speakers has by far the greatest impact on how I enjoy music listening. Most of my upgrades of the last 10 years went into room acoustics...

www.audiosciencereview.com

Dr. Edgar Choueiri explains BACCH

How does BACCH enhance the spatial realism in the reproduction of acoustical recordings made in real acoustical environments? Crosstalk cancellation (XTC) techniques, such as BACCH, suppress the sound recorded on the left (right) channel of a stereo recording at the right (left) ear of the...

www.audiosciencereview.com

Theoretica Applied Physics

Bringing 3D audio from the laboratory to the real world.

www.theoretica.us

Dutch & Dutch offers a BACCH plugin for their 8c.

Dutch&Dutch add ‘uBacch’ to their 8C active loudspeaker

The next thrilling instalment of Purité Audio’s unmissable new BLOG! https://www.puriteaudio.co.uk/blog-purite-audio-retailer-london Keith

www.audiosciencereview.com

BACCH plugin

Bring the groundbreaking BACCH 3D spatial audio technology to your 8c's, through the first third party software plugin for a loudspeaker ever. Note: Requires firmware r2.4 or later. Works only with direct streaming. More information on BACCH here.

dutchdutch.com

There are other much "less sophisticated" implementations such as Polk's SDA.

Stereo, Supersized: Inside Polk SDA Technology | Polklore

Try this little experiment: Close our eyes and listen to the sounds around you. Notice how you can easily tell where sounds are coming from, even when you can’t see them?

www.polkaudio.com

When I was at Harman International in the mid 1990s, I supervised the creation of an algorithm called VMAx - Virtual Multi-Axis. It was based on Cooper-Bauck Transaural crosstalk cancellation. It was very good when fully implemented, but back then the DSP power to do a full implementation was simply too bulky and expensive to be a commercial success. Cancelling the crosstalk was just the first step, and that is what most people do. It is, in my opinion, not what we want because the soundstage, which should be +/- 30 Deg becomes as much as +/- 90 deg, which is dramatic but totally unrealistic. The next step is important - to use HRTFs to synthesize phantom loudspeakers at the right locations. We used real speakers at +/- 10 deg and synthesized stereo or a full 5 channel surround system. It was very persuasive, and we sold simplified versions to Compaq Computers and to be incorporated into Harman Kardon receivers. Sadly, the seriously impressive version was too expensive at the time.