In Search Of Accurate Sound Reproduction: The Final Word!

[semente]

I've found this interesting opinion piece on the question of Live vs. Reproduced and one's ability to assess accuracy through listening.

 

In Search Of Accurate Sound Reproduction: The Final Word!

 

Do all audio enthusiasts have the same ability to judge high quality sound reproduction equally?

An even better question might be: “how important is the term “accurate” when describing and evaluating audio components today? 

What, if anything, does accurate sound reproduction mean for the average audio enthusiast, or better yet, should it?

 

The enjoyment and goal of accurate music reproduction is inextricably linked with the audiophile components that we use and evaluate to achieve great sound in our homes.

Of course, each individual has or acquires different needs and subjective abilities while trying to achieve this ultimate sound quality.

In the case of high definition audio reproduction, we should remember that the strive for “neutrality” in high end audio has a chain of command that THEORETICALLY ends with the individual listener; assuming of course that this is his ultimate target!

Without getting to deeply philosophical, one could argue that judging high definition sound reproduction is quite subjective in theory; while on the other hand, true “accuracy”could well be a different story altogether!

 

Looking back to the advent of high definition sound reproduction which had a huge surge in popularity in the late 1960’s, it really came to fruition in the 70’s with the help of a few particular audiophile magazines; namely Harry Pearson’s “The Absolute Sound” and particularly, J. Gordon Holt’s “Stereophile”.

These journals were revelatory in the fact that its founders, were music lovers who were trying to describe the sound of hi-fi components as closely relevant to what they perceived and heard in many live musical events both had attended throughout their lives.

While I personally did not agree with all of these authors opinions, they both had the intuitiveness of realizing that the “proclaimed” accuracy or neutrality of audio components and high quality sound reproduction should be recognized more for their intrinsic and individual tonal qualities as compared to live, unamplified sound per say, versus how the components measure up in a laboratory.

This, we all know by now is a far cry from throwing out all objective technical measurements by any means!

Technical measurements are quite useful in what they fundamentally tell us about the basic design principles of a component and the probability of them reproducing audio in a faithful and hopefully, accurate way in our home environment.

The best designers will let their ears be that final judge.

 

More importantly, both of these individuals were firm believers that high quality audio components, particularly loudspeakers, should try to bring us (if the source material permits) as close to what we remember hearing (live instruments) in a particular venue in a natural acoustic where the performance may have originated as well as trying and keep the loudspeaker neutral so it is agnostic to the type of music being reproduced.

Some reviewers today still understand this whereas others seem to have pushed it under the bus.

Still others are not even sure if it means anything to them personally at all.

However, a truthful soul will readily admit that much pop, rock and electronically manipulated program material has no relevance to live instruments in a real space and venue.

A good recording of live, acoustical instruments and voice made in a studio or setting with relatively few microphones (preferably a cross paired figure eight; (see Blumlein https://en.wikipedia.org/wiki/Blumlein_Pair ) and high quality recording equipment will reveal more about a components sound stage, stereo imaging and indeed, its sound quality than music that is intentionally and commercially manipulated for a specific effect.

The sound of the “real thing” means different things to different people but is not the aforementioned music the only true standard for judging the ultimate performance of an audio syst are quite eager to proclaim which reviewer or journals opinions he or she considers the “gospel”.

However, generally speaking, a high definition audio system that can convey this type of source material convincingly will never fail to please the prospective listener. http://www.stereophile.com/content/acoustical-standard-follow-letters

 

I will be the first one to admit that all of us high-fi enthusiasts and music lovers, rightfully, have priorities and “tastes” in music which are critical when choosing hi-fi components.

Having said that, this is quite different than proclaiming that an individual’s “tastes” in recorded music reproduction are all that really matter when auditioning the sound quality of high end audio equipment.

Quite the contrary.

While engineers, some of whom may be musicians, try to perfectly recreate a particular musical event, in fact, an individual’s ideas as to how a recording may ultimately have been fabricated in a studio may well be far removed from what he actually heard at a particular “live” event.

Let’s be blunt: an electronically manipulated and amplified source is NOT RECREATING A REPLICA OF LIVE SOUND REPRODUCTION! (Hate to say that folks…) Our hearing is interpreted by our brain.

If you’re a musician, your brain rewires itself differently.

I think that has quite a bit to do with how we perceive and process sound, independent of the audio components used to evaluate the finished product.

So then, if your tastes run awry from acoustical instruments, recordings and recording venues, it may certainly be even more challenging for you, the music lover, to evaluate a particular components true qualities and/or faults that you may come to acknowledge in your home listening environment; no?

 

(...)

 

read more at http://www.vintageandsound.com/in-search-of-sound-accuracy/

[semente]

17 minutes ago, STC said:

 

But research suggests that side and rear wall reflection is essential for realistic sound reproduction. 

 

You probably mean "research suggests that side and rear wall reflection is essential for a more credible illusion of spatial reproduction"...

 

Of course I enjoy, to a point, the fact that sounds seem to be coming from different points in space but I don't rate the spatial illusion nowhere near as highly as many audiophiles do.

To be honest I think it's accessory to music and to it's enjoyment. I attend live recitals and concerts of classical music regularly and even when I sit upfront I don't listen to as much instrument detachment or operating noises as I do from many recordings and systems.

I think it's become quite an obsession and from where I'm standing it looks as though many manufacturers, critics and audiophiles find it more significant than accurate timbre reproduction.

[semente]

31 minutes ago, STC said:

 

If you hear or able to pint the sound coming from different points than you got a problem with the setup. I mean localization of the reflected sound coming different points. 

 

No I don't have a problem with the system, perhaps I just didn't express myself clearly (enough).

Stereo (2 channel), as I understand it and hear it, creates an illusion of a soundscape located between the speakers where "images" of instruments will be positioned in a more or less similar point/place to that of the original music event (depending on the mic technique used).

If I'm not mistaken, side-wall and ceiling reflections will create ghost images (reflections) of the reproduced sound, such as those you used to get in the TV days of antenna in the roof, and also help the speakers disappear, which is why some people defend their beneficial contribution; such ghosts may give an impression of 3D-ness (a bit like stereoscopic images)

 

 

but will also mask the recorded cues of the original acoustic space, making them less appealing to those who enjoy a more natural/realistic reproduction of the original event, and will also affect both frequency response and focus in a negative way.

 

Siegfried Linkwitz has an interesting presentation on the subject:

 

http://www.linkwitzlab.com/Recording/phantom images.pdf

[semente]

A loudspeaker is not an instrument, it's goal is not to create sound (music) but to reproduce recorded sound (music).

 

And because loudspeakers produce sound in rooms, the acoustics of the listening room will interact with the spatial cues of the natural acoustic venue where the original musical event took place (excluding studio recordings, which don't have those natural cues).

The less your listening room interferes with the reproduction, the more of the original event you'll be able to listen to.

 

Furthermore, if you want your system to reproduce an instrument as if it were playing in there with you this instrument would have to be recorded in free-space (anechoic).

 

In most studio recordings the various instrument are recorded in semi-anechoic conditions, sometimes in different studios, often in mono; EQ, panning, reverb and adjustements in level are made during mixing and this will create an artificial ambience which may benefit from some room contribution and even the extra low even order harmonic boost...

[semente]

33 minutes ago, fas42 said:

if the playback is lifted to a very high standard then the ambience expressed by the recording will completely dominate; your listening room "disappears", to be replaced by those spaces encoded in the recording.

 

I don't agree with this sentence, unless you are including the room in the "playback lifted to a very high standard".

The room cannot disappear unless you treat it, it's got nothing to do with the quality of the playback, even if controlled narrow dispersion in the upper mids and highs deals better with the room "conflict".

But a lot of people enjoy that "interference" to the point of positioning their speakers close to the side wall with little or no toe-in.

It also looks from what I read in forums and webzines like many audiophiles and "pro" critics perceive flat response as "dull" or "lifeless", although most of them do not listen to unamplified acoustic music.

 

R 

[semente]

21 minutes ago, STC said:

 

What is low level of room interaction? Nearfield listening?

 

That or some degree of side-wall and ceiling absorption.

[semente]

3 hours ago, AJ Soundfield said:

You are mistaken. 

Precedence effect holds (no "echo") when there is a spectral similarity between the direct and reflected sounds. It will only break down when there are gross dissimilarities...aka terrible speakers with poor off axis (entirely possible for audiophiles).

An excellent layman article is written here by Dr Toole http://www.audioholics.com/room-acoustics/room-reflections-human-adaptation/what-do-listeners-prefer with references to the many studies showing so.

 

cheers,

 

AJ

 

The keyword in that article is "preference".

[semente]

1 hour ago, STC said:

 

I am sorry, I do not agree with you. My two speakers completely disappear even without the aid of rear half reflection. The ghosting image is more relevant when we reproduce the original single source with two speakers.

This is what happens with stereo trying to reproduce a single source - distortion.

 

This is how the waves in a reflection free room travel before reaching us.

 

 

 

 

 

Now when you reproduce the sound with stereo speakers, the waves are distorted compared to the real sound.

 

 

 

 

The animation charts were taken from ISVR website.

 

What you say/show is correct, bit I wasn't discussing live source VS. reproduction but sound of speakers in a room VS. sound of speakers in free space (anechoic). 

[semente]

41 minutes ago, Ralf11 said:

re:  side-wall and ceiling reflections will create ghost images (reflections) of the reproduced sound

 

do you mean the use of a 'ghost' source beyond the reflective barrier to better model room acoustics?

 

or that a ghost source will be perceived by a listener at certain levels of time lag?

 

The wall acts as a mirror and the resulting reflections, which are not part of the recorded signal, give the image a bit of "relief".

It may sound pleasant to the large majority but it is still a form of distortion.

I think that the image I posted previously is not a bad illustration of what I am trying to express.

 

R

[semente]

5 minutes ago, firedog said:

Or that, or a large room with enough space to minimize room reactions between the speakers and listener, or a room treated with acoustic panels.

 

Interestingly I have a hunch that most audiophiles would not like either... 

[semente]

3 minutes ago, AJ Soundfield said:

Correct and "blind". It falsifies the image you posted.

Turns out, ears only, most folks, including believers/studiophiles/etc.  prefer reflections with good polar pattern speakers. Exceptions are terrible speakers and of course sighted belief preferences for the latest iso-ward fashions.

Reflections are critical for stereophonic phantom center spatial rendering. For ears i.e.

 

So you are saying that stereo imaging doesn't work outdoors.

That is not my experience.

[semente]

Just now, AJ Soundfield said:

Of what? There is no reference acoustic transduction. So "distortion" of what?

Once again 2ch sampling of any soundfield is itself a "distortion". See link above.

 

Of the signal.

[semente]

29 minutes ago, AJ Soundfield said:

Nope, I'm quoting you saying that 

 

Lateral reflections spatially average/smoothen the stereo phantom central imaging combing. Lack of reflections worsens the audible combing.

The (ears) research is clear.

 

Do they smoothen combing or just mask it?

Reflected sound is delayed.

[semente]

11 hours ago, AJ Soundfield said:

Both 

 

Correct, but that isn't always bad and often very good, especially with stereo.

Again, as long as no precedence breakdown.

 

 

I don't know if you've listened to the Sonus Faber Stradivari.

These speakers have a very wide baffle and, as a consequence, the lateral dispersion starts to narrow above the presence region in a gradual but even manner, and listening to them in a large room (16m front wall) was a very enlightening experience in regards to stereo imaging:

 

Sonus Faber Stradivari, lateral response family at 50", normalized to response on tweeter axis, from back to front: differences in response 90 degrees–5 degrees off-axis, reference response, differences in response 5 degrees–90 degrees off-axis (source)

 

 

This is, of course, a very unToole-like approach, who defends that there shouldn't be any roll-off off-axis before we're into overtones territory:

 

Revel Ultima Salon2, lateral response family at 50", normalized to response on tweeter axis, from back to front: differences in response 90–5° off axis, reference response, differences in response 5–90° off axis (source)

 

 

Then we have the BBC Research Department approach.

The group research was public funded and did extensive work in speaker development both in technical and psychoacoustics terms, and they made use of experienced sound engineers and orchestras from the Broadcasting company to perform live vs. reproduced comparisons (something that would be impossible today even for the wealthiest manufacturers).

They also showed a preference for wide-baffle speakers and defended that the off-axis response should relax in the presence region as can be seen in this BBC-inspired model:

 

Harbeth Super HL5+, lateral response family at 50", normalized to response on upper-tweeter axis, from back to front: differences in response 90–5° off axis, reference response, differences in response 5–90° off axis (source)

 

 

Earl Gueddes goes further and proposes that power response and axial response "should fall gradually" as you enter the mid ranges "while maintaining a flat directivity index" (source).

 

 

An then you have horn speakers, such as the Avantgarde Uno which sports constant midrange and treble and directivity:

 

Avantgarde Uno Nano, lateral response family at 50", normalized to response on optimal axis, from back to front: differences in response 90–5° off axis, reference response, differences in response 5–90° off axis (source)

 

 

According to Toole's research the large majority will not like the horns, and from what I read in forums he is right.

What I don't agree is that using side wall reinforcement is more accurate.

 

 

But you are a speaker designer so perhaps you already know all these things.

 

R

[semente]

11 hours ago, AJ Soundfield said:

Both 

 

Correct, but that isn't always bad and often very good, especially with stereo.

Again, as long as no precedence breakdown.

 

Bad is a matter of preference, unrelated to accuracy.

[semente]

12 minutes ago, STC said:

 

Last couple of years I make recordings of my progress for reference to know exactly what I do is correct and not just placebo. Trust me the rear half wall enforcement ( provided correct and even across the frequencies) can provide you the best listening experience even with low entry system. I have sample to prove for AB.

 

Here is the video of my playback captured with a binaural recordings from my listening chair. When you listen to the sound with the headphones you should feel the ambiance enveloping you. Although, the cheap $75 dollar mic didn't capture all the low level ambiance, still you should hear the difference. Of course, the quality is limited due to cheap ambiance speakers but this sound is more realistic and better representative of actual sound.

 

At 58 seconds, only the sound of my rear half (wall enforcement is heard). As you can hear they are quiet high and yet it integrate with the main sound perfectly. Of course, Wall enforcement helps large ensemble and may not be suitable for studio recordings. 

 

https://youtu.be/PYNXNZr9a7A

 

 

 

 

Your system is not 2 channel stereo and you seem to be using dipole speakers so that information is not very relevant to this discussion.

 

What do you mean by "rear half wall enforcement"?

Which frequencies are you reinforcing?

How does that affect tonal balance?

I don't much care about spatial realism (soundstage, immersive or not), a reasonably credible imaging effect is just fine.

 

And I find those 2Lno recordings nonsensical...the mics/listener surrounded by instruments?

 

 

[semente]

11 minutes ago, STC said:

 

It is. I will add 4.) or 5.1 later.

 

Wall enforcement is basically enhancement of a frequencies with the help of the wall or convoluted speakers that act like wall. Naturally, It is impossible to to get good sound with more than 0.6second reverberation in a typical room. And here you are listening reverberation upto 2.2 seconds.

 

Is this discussion only meant for 2 speakers only or two channel stereo?

 

No, of course not, we can discuss other setups, just not mix them for sake of clarity.

 

Most speakers go omni below ~300Hz so there is bound to be reinforcement and floor-bounce and Allison cancellation effects at those frequencies; but as far as I know there is very little spatial information in this range.

What is your opinion regarding horns?

[semente]

6 minutes ago, STC said:

 I am still here. How to reproduce accurate sound? Are two speakers enough? If they are, then I am soryy to miss the point. I ,generally, do not like horns. 

 

I was hoping you'd be a bit more specific in your comment regarding (what you dislike about) horns.

 

As for your question, I would say that you need a single speaker, no more and no less, to accurately reproduce one channel; two channels, two speakers, etc.

[semente]

4 minutes ago, AJ Soundfield said:

Yes and I've heard all the designs you've listed, Several local audiophile club members have/had Strads. There are three Trio and one Uno owners in the club, one is a AG dealer. Ditto for Salon2 and Harbeth (also have dealer in club). None of them, including my own, are "accurate", because that exists only in the minds of audiophiles/studiophiles.

 

To what?

 

This is how I see it: if you play a signal through a speaker in an anechoic chamber this will define the speaker's accuracy.

When you move the speaker into a room, the degree in which the room affects the transduced signal depends on the way sound (through directivity) interacts with the room before it reaches the listener.

 

You may have heard about an experiment that Gradient Labs performed many years ago in which they compared the accuracy of several speakers by inserting a speaker into one channel.

The speaker would reproduce the signal/music in an anechoic chamber and this sound was then fed live into the corresponding speaker of the 2 channel setup placed in a listening room.

[semente]

1 hour ago, mansr said:

What was the outcome?

 

I don't know which speakers were tested but as far as I remember the only one that was not identified as being in the chain was the BnW 801F.

[semente]

1 hour ago, AJ Soundfield said:

So an "accurate" listening room is an anechoic chamber.

While my microphones would agree, my ears do not.

Yes, I'm an AES member and acutely aware of Salmis work, including his Absolute Listening Test.

It does not conflict with the current research, unless misunderstood. I'm linking articles too.

Reflections per se are not perceptually "bad", unless spectrally disambiguated from their onsets ("direct" response).

Once again, the research is clear. Unfortunately, a lot of folklore persists, but 'tis the way of this world.

 

 

I am not contesting that they are not ' perceptually "bad" '; in fact research shows that is what most people seem to prefer. I prefer a "dryer" sounding room, or less room contribution if you prefer but that is just a matter of taste.

 

I have browsed your website when you started contributing to CA, it would be interesting to have a look at the measurements of your larger speakers.

 

R 

[semente]

1 hour ago, AJ Soundfield said:

...and belief. Many of those tested in the papers Toole referenced were (sighted) treatment believers. The results said otherwise.

The McGill follow ups were specifically of studiophiles, who hold even stronger beliefs about "treatments" etc. Those results were even funnier...

 

This is not a criticism to their work but the Toole school is not as dominant here in Europe as it in North America and you don't have to be an expert to realise that several aspects of speaker design are not consensual amongst loudspeaker designers.

It's a very flawed element of the playback chain and designers seem to pick whichever compromise they find works best for them.

 

 

I had never thought of that - the placebo effect of room treatments (more specifically side wall treatments) - but it does makes sense.

But I don't think that room treating is a widespread practice amongst audiophiles.

 

I don't have a dedicated listening room and because almost all forms of commercial treatments look awful I am using bookcases to partially cover side walls and drapes over the large window behind my back.

The living room in my current home is quite small but fortunately it allows for a long wall setup which greatly reduces side wall interference.

 

R

[semente]

1 hour ago, Ralf11 said:

I know what a placebophile is, but what is a studiophile?  Tho I can guess...

 

That is a good question...

[semente]

11 hours ago, fas42 said:

what I learned over the years is that a competent system can be plunked down into any location, as shambolic as you like, and it will always "sound right".

 

10 hours ago, STC said:

 

Not in my case. I am unable to see how a competent system can be any different from real instruments when dealing with room acoustics. 

 

I agree.

There's a best spot for your speakers and a best spot for the listening chair in every room.

Setting up a pair of speakers correctly is hard work, add two more speakers and this will increase the problems exponentially.

[semente]

10 hours ago, STC said:

 

No, you should not reject. It is not polite.   But to argue that a string quartet is going to sound as good as it sound in Carnegie hall in your living room then..................

 

The concert hall here has a movable ceiling which would be lowered or lifted higher depending on the size of the ensemble. One size doesn't ft all. Just like a rock band would sound different in a concert hall, it is impossible for one fixed acoustics environment can replay different genre accurately. There will be a compromise somewhere.

 

 

 

The best venues will even have a smaller room for small groups and solo recitals.

The only reason why you get to listen to them in a large hall is profit $€£!!!