What determines "believability of the reproduction illusion"

[fas42]

I totally agree and have always agreed with the importance of electronics, or else I wouldn't have bothered to build my own.... but the one thing that isn't correct is that rooms can be "acoustically invisible", let alone ordinary rooms. I think the issue is there are room effects that make a big difference and others that do not, you seem to group them all into one category which is not correct.

To this point I haven't had an experience where the room had any significant impact, but bear in mind I never pursue deep bass in my efforts - if a system was specifically organised to produce the very low frequencies at correct levels then everything could change, I haven't been in a situation to investigate this.

Acoustic invisibility of the room is my goal, always - this builds in quality as the playback chain improves, and is a measure of where the system tune is at. One of my "measuring sticks" is the original release of Led Zeppelin I on CD, which creates cavernous soundspaces extending way beyond the boundaries of the house; this would be one of the first test recordings I would use to evaluate an unknown system claiming high performance ...

 

[Al M.]

Al , my speakers are 38% the length of my room (8m) into the room , definitely gives a lot of depth the soundstage, on an aural and visual basis .They are in free space so to speak

Wow, 10 feet into the room, that's amazing!

 

[Al M.]

Al, I just had a look at that thread and it's very interesting what your experience was - I'll comment on it from my angle.

You say that without room treatments the soundstage was flat, but then with the addition of the adjusting of the room aspects the depth factors, etc, were greatly improved - my take on this is that there were enough artifacts in the direct sound which after interaction with the room prevented the listener's mind from understanding the acoustic cues sufficiently to "see" the 3D information. Moderating the room allowed the mind to deal far more specifically on the direct sound, and spatial information in the recording now made sense; when that equilibrium was disturbed by removing the tube traps the additional "chaos" in the sound was now too much, and believability was strongly impacted.

This follows on from what I have said many times: room treatments are one way of allowing the mind to focus on the information in the recording, but IMO the better alternative is to improve the quality of actual sound at the point when it's produced by the surface of the speaker drivers; "improving" here means reducing the level of audible artifacts which are added by the playback chain.

What happens for me is that the soundstage is never flat, once the electronics are sufficiently sorted - the world of the recorded event extends from the speakers back to as far as the acoustics of the recording say it should go; in some instances this stretches for 100's of metres, figuratively speaking.

O.k., so far I have kept a certain level of patience, but now I have to ask:

Are you serious, Frank, or are you just trolling?

Moderating the room allowed the mind to deal far more specifically on the direct sound, and spatial information in the recording now made sense;

This is the one part in your post that makes sense and seems acoustically correct: when you remove unwanted room reflections that interfere with the spatial information from the recording itself, then that information is allowed to shine through.

 

[fas42]

O.k., so far I have kept a certain level of patience, but now I have to ask:

Are you serious, Frank, or are you just trolling?

What particular point are you referring to, Al - perhaps that the sound stage is not flat with sorted electronics?

 

[PeterA]

fas42, how important do you think speaker and listener seat positioning is? Can you have a 3D soundstage if the electronics are sorted out but the speakers are haphazardly located in the room or the listener is seated in a corner? I think I remember you writing that once you have corrected the electronics in your projects that one can get a realistic sense of staging and imaging from anywhere in the room, or am I mistaken?

 

[fas42]

Peter, that's correct. With sorted electronics the acoustics of the recording dominate, and staging and imaging all fall into place irrespective of the location of speakers and listener. This happened to me completely unintentionally the first time, and ever since issues with locations and room have not figured in my experiments, because they have never seemed important - I knew what quality level was required to be fed to the speakers as the first priority, and this automatically gave me the satisfying listener experience, every time.

John, jkeny, was the one who steered me into looking very closely at the field of ASA, which gave me the answers as to why this behaviour when hearing could manifest; I had always been curious about what was happening when listening which caused the illusion to be so convincing, and the ideas and findings in ASA beautifully answer this ...

 

[PeterA]

Peter, that's correct. With sorted electronics the acoustics of the recording dominate, and staging and imaging all fall into place irrespective of the location of speakers and listener. This happened to me completely unintentionally the first time, and ever since issues with locations and room have not figured in my experiments, because they have never seemed important - I knew what quality level was required to be fed to the speakers as the first priority, and this automatically gave me the satisfying listener experience, every time.

John, jkeny, was the one who steered me into looking very closely at the field of ASA, which gave me the answers as to why this behaviour when hearing could manifest; I had always been curious about what was happening when listening which caused the illusion to be so convincing, and the ideas and findings in ASA beautifully answer this ...

That's interesting. Have you ever heard better electronics like Spectral, Pass, Lamm, Solution, Dartzeel, etc. with which you were sufficiently impressed that you did not to have to modify them? That is, have you heard electronics that met your standard of "being sorted out" enough not to need modifications, and if so, did they also dominate the quality of a system so as to make unimportant the speaker and listener locations in a room?

If these more expensive lines of electronics don't meet your standards, or even if they do at their considerable prices, have you considered selling lower cost electronics that you have modified to start a business? It seems to me that you very much enjoy modifying electronics and the challenge of getting them to meet your standards.

 

[Steve williams]

Rightly or wrongly I find the concept of ASA interesting Frank and it is certainly food for thought how ever to say the following....

staging and imaging all fall into place irrespective of the location of speakers and listener.

and to use ASA as a rationale for causality, I don't know enough to say yea or nay to your argument but I just cannot admit to rationale in your statement above. Help me understand how things fall into place regardless of location of speakers and listener

 

[fas42]

That's interesting. Have you ever heard better electronics like Spectral, Pass, Lamm, Solution, Dartzeel, etc. with which you were sufficiently impressed that you did not to have to modify them? That is, have you heard electronics that met your standard of "being sorted out" enough not to need modifications, and if so, did they also dominate the quality of a system so as to make unimportant the speaker and listener locations in a room?

If these more expensive lines of electronics don't meet your standards, or even if they do at their considerable prices, have you considered selling lower cost electronics that you have modified to start a business? It seems to me that you very much enjoy modifying electronics and the challenge of getting them to meet your standards.

Yes, on several occasions. Interestingly, a couple of those were pro audio situations, sound reinforcement of stage, visual productions - so no idea on what was being used, but the person behind the setup of those systems obviously had good understanding and could assembly the parts into a coherent whole. The last one was a combination of Bryston and Dynaudio at an audio show - it certainly can be had if the right combination, probably fortuitously, is assembled.

I have considered attempting a business along these lines, but there are a few obstacles. Many times, in fact mostly, it is about ensuring that the system as a whole is sufficiently competent, and the lower the cost of the units the more an effort has to be made at engineering the system overall; this is something like a speaker designer coming into your home and adjusting his, costly product for optimum performance, fiddling for hours or days to get everything just so. Then there is the fact that I have spent a long time trying to get a handle on all the factors that matter, and this has meant that I couldn't be sure in a given situation whether I could optimise what mattered in a reasonable time frame - I know that given unlimited access to the system over an indefinite period that it can be "groomed" to give a result, but is the other person that patient? Lastly, I'm not a natural businessman, I'm an ideas person by nature, so have a reticence to trying to make this work as a money spinner.

 

[fas42]

Rightly or wrongly I find the concept of ASA interesting Frank and it is certainly food for thought how ever to say the following....



and to use ASA as a rationale for causality, I don't know enough to say yea or nay to your argument but I just cannot admit to rationale in your statement above. Help me understand how things fall into place regardless of location of speakers and listener

Steve, one of the key ideas of ASA is that when listening to something, anything, that there are two processes at work in us, in terms of how the hearing system operates. First is the actual sound waves hitting the ear, the pure, raw acoustics information being registered by the eardrum, etc, and turned into electrical signals - this is termed bottom up processing, and is what the audio community normally worries about in nearly everything written about getting good sound. Then, the other side of what's happening is that the brain anticipates what it is about to hear, based on what has already been heard - this is called top down processing, and is the heart of how the mind can experience an illusion, believe something is there that is not in fact the case. This is very well known, understood in the visual field, and has been for some time - the key movement forward was that ASA proposed that exactly the same occurs for auditory processing; and experiment after experiment has since verified that in fact this is the case ... we can "hear" something which by every measurable means is not there!

So, the ear registers sound around us, and the brain expects to hear "something", based on what has happened up to that point - how this then works is that a dynamic balance, and the word "balance" is a key part of the concept, occurs between the two processes; there is a constant correlating between the two activities, split second by split second. Listening to a live piano being played is a good example: you're in the room listening close to the instrument, and then leave the room, move elsewhere in the house - all the time you hear that piano being played, there is no sudden loss of the sense that this is happening. But if one was to measure what the sound waves were in the piano room, and also at the other end of the house this would seem ludicrous - the dramatic loss of acoustic information well away from the piano would make this seemingly impossible to maintain. But what's actually happening is that the brain is picking up clues from what the ear is registering that confirm what the mind expects: I believe a piano is being played down there, and nothing I hear conflicts with that.

Getting back to audio, that mental processing balance needs to be satisfied, for an illusion of a real musical event to form. If the information the bottom up processing receives from the ear is too much in conflict with the brain expects, top down, then the illusion fails; the balance is no longer there. So if one is standing well to the side of an audio system and the direct sound is no longer as strong as room echoes, and there are too many artifacts in the sound itself, then the confirmation that the brain expects is not there - the imaging and staging no longer jell, and the illusion fails. It's all about keeping this mental balancing in equilibrium; if the auditory information always confirms what the brain anticipates then the illusion is maintained.

 

[Rodney Gold]

If you dont have the need for bass.. then things become simpler.. however the statement that you can get top quality imaging anywhere in the room regardless of speaker and listening position is beyond my comprehension

 

[NorthStar]

? http://www.enjoythemusic.com/magazine/viewpoint/1101/abcstereomagic.htm

Excerpt:

"Audiophiles, on the other hand, have developed their own detailed terminology to deal with the spatial perception of two-channel audio. Soundstaging, imaging, focus, depth perspective, stage width, and image palpability are descriptive of spatial impressions. These terms originate from our everyday experience in localizing sounds, yet they go beyond the concert hall experience. My personal conclusion is that the home hi-fi experience is distinct from that of live music. First of all, you can't beat the illusion of being there when you are actually there. The combination of aural and visual cues, the sensation of being enveloped by sound, these are all unique to concert hall sound. Its quite a trick, even for a high-end system, to transport the listener to a different space or, alternatively, to import a concert hall acoustic into your own living room. Bottom line: it's all an illusion. Close your eyes, dim the lights, have a glass of wine, smoke your favorite herb - do whatever it takes to heighten the illusion. But in truth, there are no musicians arrayed between the speakers. Second, high-end audio has succumbed to a quest for heightened reality, with more detail, and greater focus than that of the real thing. I've yet to hear holographic imaging or pinpoint focus in a concert hall. The effect is partly an artifact of multi-mic, multi-track recording techniques, which generate extreme near-field recordings with artificially etched detail and jumbled perspectives. The quest for detail and focus at all costs has driven a wedge between audiophiles and music lovers. If you still value timbre and dynamic integrity above all else, count yourself as a music lover. If, on the other hand, you delight at the discovery of subtle noises such as lip smacking or foot tapping, previously buried in the mix, then take my word for it: you're an incurable audiophile.

In either case, something we all appreciate is a 3-D soundstage. Unfortunately, getting there is often a non-trivial task, made all the more difficult by the necessity of having to integrate a sound system into the confines of a domestic living room. It is critical at the outset to understand the limitations of two-channel or conventional stereo. Its major fault is that all of the sound, direct and reverb, is presented from a plane between the speakers. Natural reverb, by its very nature, envelops the listener from all directions. The immediate impact of funneling reverb entirely through the right and left speakers is to place the listener's perspective outside that of the venue, looking in through a window. Ironically, it is room reflections, whose role is often misunderstood by the average audiophile, that distribute ambient information more naturally in the listening room. The misguided motto of "the only good reflection is an absorbed one," has driven too many of us toward heavy absorptive treatment of the wall surfaces immediately adjacent to and behind the speakers. The ultimate expression of this approach is the dead-end/live-end listening room. Although this makes some sense in a recording studio monitoring environment, it rarely works in a domestic environment. Try listening to a stereo recording in an anechoic chamber - an entirely echo-free acoustic. You'll be surprised by the sterility of the presentation. In the case of two-channel audio, the room is not the enemy, but rather it must be used intelligently to achieve the most believable illusion of space. Incidentally, over half of the sound intensity at the listening seat in a typical domestic listening environment derives from room reflections."

 

[fas42]

If you dont have the need for bass.. then things become simpler.. however the statement that you can get top quality imaging anywhere in the room regardless of speaker and listening position is beyond my comprehension

It's quite bizarre when you first hear this happening, you shake your head with disbelief, and move around the room, trying all sorts of things to "shake it" - but if it's really well established it remains rock solid no matter where you move. A proviso does come from this ASA research now occurring, they're using the results to date to establish why people with various types of hearing disorders may have problems, and some of it has to do with the fact that the hearing of some people doesn't work in the way I just described - their brains can't or don't correlate the ear data with an internal interpretation of what's happening.

So, some people will never experience this type of illusion, no matter what - something to keep in mind ...

 

[Rodney Gold]

Hmmm..so my hearing or brain is suspect ?

 

[fas42]

Hmmm..so my hearing or brain is suspect ?

Nope ... just that there are no guarantees that the difference will be heard, ! It is hard to get a conventional system to the point of this believability, the audio friend who lives locally has taken a large number of cues from me about what to do, but still hasn't quite got over the hurdle - his quality of sound is very impressive at times, it's oh so close - but, no cigar!! It's his system, he obviously wants to fiddle with it in a way that pleases him - I just offer advice on what he might consider looking at, which sometimes he quietly ignores, indefinitely ... .

 

[PeterA]

That's interesting. Have you ever heard better electronics like Spectral, Pass, Lamm, Solution, Dartzeel, etc. with which you were sufficiently impressed that you did not to have to modify them? That is, have you heard electronics that met your standard of "being sorted out" enough not to need modifications, and if so, did they also dominate the quality of a system so as to make unimportant the speaker and listener locations in a room?

If these more expensive lines of electronics don't meet your standards, or even if they do at their considerable prices, have you considered selling lower cost electronics that you have modified to start a business? It seems to me that you very much enjoy modifying electronics and the challenge of getting them to meet your standards.

Frank, could you address the question in bold? I am curious, because every system which I have heard that includes some of these more expensive, well designed electronics still benefitted from judicious placement of speakers and listening seat in the room to sound believable or convincing. The quality of the electronics was not enough to provide a realistic illusion. During demonstrations it is obvious because of the many seats in the room. There is almost always one seat which is better than the others for sound quality.

Have you ever tried to modify some of the gear that I mention? If so, how did it improve?

 

[Rodney Gold]

It does not happen that imaging etc is constant all over the room..

 

[FrantzM]

If you dont have the need for bass.. then things become simpler.. however the statement that you can get top quality imaging anywhere in the room regardless of speaker and listening position is beyond my comprehension

you're not alone.. What I find amusing is how many legs are being pulled....

 

[microstrip]

It does not happen that imaging etc is constant all over the room..

No it does not happen. However some aspects fundamental to believably keep stable in a large part of the room and most of all the variation is continuous - if moving you do not feel uncomfortable.

I have found that once a system is playing with believability you find that you are much less exigent with the classical pint point type imaging. The proper size of objects is created by their dynamics and richness, not only by the localization cues.

 

[jkeny]

I don't fully subscribe to Franks's view of things but I will say that normal rooms which are intelligible to talk in are fine to me as far as playing music in Intelligibility of rooms is all about the ratio of direct to reflected sound & if this is fine why would I need to change this ratio? (like Frank, I'm not a bass freak).

What I want from my music listening is a window into the performance (when there is a performance actually recorded) - i.e. an appreciation of the recording as an event with the interplay between musicians evident - often this becomes more evident & better portrayed when the noise floor (modulation?) drops below a critical level where the nuances of the performances become more evident & where the timing seems to snap into place. I find that 3D soundstage & solidity of the soundstage naturally result from this & maybe this is what Frank is talking about? I don't just want detail, I want low-level detail that brings believability to the performance & has some relevance. Of course not all recordings are recordings of live performances but even those that aren't are enhanced by this. It's really the difference between what people often report as "lifeless" reproduction Vs reproduction that grabs & retains your interest - the same notes are being portrayed but there is something else that is also being portrayed in the reproduction that has emotion.

To me this change from lifeless to emotion filled reproduction doesn't happen because of a change of speaker or room treatments - it happens at a much more fundamental level which involves the electronics. Can it be enhanced by room treatments? Possibly but getting to this level first is difficult & usually satisfying enough without looking for room enhancements.

That's what I meant by the thread title but it's interesting to hear others views too.