State-of-the-Art Digital

[acousticsguru]

45 years ago, Cabasse showed everyone how to build phase-correct loudspeakers. OK, nowadays it is more important that they look good and have a perfect housing and the rest is secondary. Some manufacturers should ask France how it is done.View attachment 147162

Needless to say, what they did back in the era was to shift the acoustic centers of drivers (in theory: where electrical energy is converted into acoustic, i.e. sound waves) based on the assumption that moving the respective voice coil air gaps into a plane would do the trick. That’s a part truth, the exact same that Wilson’s claim to time alignment is based on. It says little about the more important part of the equation: whether or not the drivers play in phase, whether their acoustic output sums, and over a sufficiently wide range, and what the speaker’s off-axis behavior looks like (and hence its in-room response, which is the sum of direct and indirect sound at the listening position, and preferably also elsewhere in the room). Not to mention we’re looking at a rectangular box with sharp corners causing diffraction, although at least not all of it equal distance (summing up).

Greetings from Switzerland, David.

 

[DasguteOhr]

Needless to say, what they did back in the era was to shift the acoustic centers of drivers (in theory: where electrical energy is converted into acoustic, i.e. sound waves) based on the assumption that moving the respective voice coil air gaps into a plane would do the trick. That’s a part truth, the exact same that Wilson’s claim to time alignment is based on. It says little about the more important part of the equation: whether or not the drivers play in phase, whether their acoustic output sums, and over a sufficiently wide range, and what the speaker’s off-axis behavior looks like (and hence its in-room response, which is the sum of direct and indirect sound at the listening position, and preferably also elsewhere in the room). Not to mention we’re looking at a rectangular box with sharp corners causing diffraction, although at least not all of it equal distance (summing up).

Greetings from Switzerland, David.

Just listen and judge for yourself. Whether active Albatros V (photo above used in good condition 7-8k€) or passive brigantin speaker~95db/ 1watt, for me they are the benchmark (4-way speaker) from that time and still are today.

Today it would probably cost as much as the big Wilson 1982 (35,000 DM), the effort was enormous back then. For me it's still in the top 3 of everything I've ever heard.

 

[microstrip]

Ignorance? I mean, seriously, none of this is new. None of this is a design choice, or a matter of voicing. These are flaws. Equal distance quadratic baffles so the same type of diffraction multiplies is a known flaw. Getting the respective acoustic centers of drivers onto a plane is a great idea, but doing so with drivers that measurably do not play in phase is nonsense, and hence a flaw. Any speaker Designer worth their salt knows this, and if anything they’ll explain away compromises such as putting all drivers into one flat baffle referring to cost, which is a justifiable argument. But doing the contrary in a cost-no-object product defies logic. Except, of course, it’s a clever marketing gimmick that apparently sells speakers, so philosophically speaking, one might say all of this makes sense? But the question was, why does the brand sell and still have an iffy reputation: well, because they keep doing things that been proven to be a design flaws (electrically is one thing, but more importantly, physically, and sound is physics!) decades ago already.

Greetings from Switzerland, David.

Wilson speakers are not in phase and their acoustic centers of drivers are not in a plane. What they call "time alignment" is simply being in phase at the crossover frequencies. This has been addressed several times, even by David Wilson long ago.

All speakers have compromises. IMO what you are calling flaws are Wilson design options. In fact , I am used to such perspective. In his excellent book on sound reproduction FLoyd Toole also addresses the characteristics of speakers that do not follow his preferred scientific model as "flaws". This did not prevent me to appreciate and have used with great enjoyment designs he considers "flawed" and discard speakers designed according to his model, as they did not please my preferences.

Edit - Just to clarify things "time alignment" is not the same thing as "phase coherent" or "point like speaker". It affects sound - some people like Wilson "time alignment" , others not so much.

My favorite quote in the high-end: (please guess or search who wrote it)

"If you are concerned that your xxx (or anything else for that matter) is as objectively and technically accurate as possible,
that is a perfectly legitimate criterion. You will certainly find many
products in the marketplace that excel at conventional objective
performance, and most of them are much cheaper.

Our real customers care most about the experience they get when
they sit down to listen to their music. We create xxx that we
like to listen to, on the assumption that we share similar taste. "

"In the end, the subjective experience is what our customer is looking for. Our taste in sound may not appeal to everyone, but it's what we have to work with, and we only need a small segment of the market to be successful. "

 

[No Regrets]

I can honestly say that a lot of the technical discussions and measurements oftentimes go way above my head... maybe, I just need to sit up straighter, lol.

At the end of the day, what sounds right to me and gives me the musical enjoyment that I can appreciate... that is what's most important to me. I leave the tech and specs to the designers.

With that being said, the speakers that i have owned since the 90's have given me much sonic pleasure and I have had no plans to replace them, because they sound right to "me". I own the Dunlavy SCIV's Signatures. John Dunlavy, the designer was a very smart and intelligent man, having several patents. Measurements meant a lot to him and helped him with his designs. I remember reading in a Stereophile review talking about John Dunlavy's measurements; this is taken from the review which can be found here https://www.stereophile.com/floorloudspeakers/99dun4/index.html

"Ah, but there's measurement, and then there's measurement. Designer John Dunlavy specifies a "full" set of "credible" measurements. He measures everything about a speaker's behavior, paying particular attention to the impulse response, measured anechoically at the typical listening distance of 10'. He points out that accurate impulse response implies flat frequency (amplitude) response, but not vice versa (footnote 2). Thus, a speaker with flat frequency response (on-axis or integrated over various angles) may be quite inaccurate when it comes to reproducing an impulse signal; ie, the outputs of the different drivers may be arriving at different times.

Dunlavy argues that pulse coherence is essential for the speaker to be considered accurate. He draws an analogy between a cheap lens, with marked spherical/chromatic aberration that blurs the image, and a speaker with a lack of pulse coherence, resulting in blurring of the sonic image."

Then from John A. measurements...

"Turning to the time domain, fig.3 shows the SC-IV's impulse response on the tweeter axis. (The speaker-stand reflection reveals itself as the small dimple in the plot just before the 12ms mark.) Though it's hard to tell anything from a raw impulse response, the simple up/down shape with minimal overshoot implies excellent time coherence. (The only speaker on which I've measured a similar impulse response is the Quad ESL-63.)

Fig.3 Dunlavy SC-IV, impulse response on HF axis at 3m (5ms time window, 35kHz bandwidth).

Look at the SC-IV's step response in fig.4. Pretty ideal—the outputs of all the drive-units arrive at the microphone at pretty much the same time. This, by definition, is time coherence. As a result, the SC-IV is one of the only two loudspeakers I've encountered that can produce a good squarewave shape. (The other was, again, the Quad ESL-63.) And this was over a wide bandwidth, from 200Hz to 5kHz. Although the subjective effects of a loudspeaker featuring time-coherent behavior are not fully understood, my subjective impressions have been that such designs always feature superb imaging and soundstaging. The SC-IV is no exception."

Again, I have no idea if it's because of John Dunlavy paying attention to various critical measurements that I love the speaker's sound so much, or if the measurements simply confirm that John Dunlavy's design ideas had merit.

All I know is that enjoy the music coming from these speakers and that at the end of day, it is what matters most to me. It's my hope that everyone can have enjoyment from their music systems, no matter what equipment they may employ.

Best wishes to all,
Don

 

[morricab]

I can honestly say that a lot of the technical discussions and measurements oftentimes go way above my head... maybe, I just need to sit up straighter, lol.

At the end of the day, what sounds right to me and gives me the musical enjoyment that I can appreciate... that is what's most important to me. I leave the tech and specs to the designers.

With that being said, the speakers that i have owned since the 90's have given me much sonic pleasure and I have had no plans to replace them, because they sound right to "me". I own the Dunlavy SCIV's Signatures. John Dunlavy, the designer was a very smart and intelligent man, having several patents. Measurements meant a lot to him and helped him with his designs. I remember reading in a Stereophile review talking about John Dunlavy's measurements; this is taken from the review which can be found here https://www.stereophile.com/floorloudspeakers/99dun4/index.html

"Ah, but there's measurement, and then there's measurement. Designer John Dunlavy specifies a "full" set of "credible" measurements. He measures everything about a speaker's behavior, paying particular attention to the impulse response, measured anechoically at the typical listening distance of 10'. He points out that accurate impulse response implies flat frequency (amplitude) response, but not vice versa (footnote 2). Thus, a speaker with flat frequency response (on-axis or integrated over various angles) may be quite inaccurate when it comes to reproducing an impulse signal; ie, the outputs of the different drivers may be arriving at different times.

Dunlavy argues that pulse coherence is essential for the speaker to be considered accurate. He draws an analogy between a cheap lens, with marked spherical/chromatic aberration that blurs the image, and a speaker with a lack of pulse coherence, resulting in blurring of the sonic image."

Then from John A. measurements...

"Turning to the time domain, fig.3 shows the SC-IV's impulse response on the tweeter axis. (The speaker-stand reflection reveals itself as the small dimple in the plot just before the 12ms mark.) Though it's hard to tell anything from a raw impulse response, the simple up/down shape with minimal overshoot implies excellent time coherence. (The only speaker on which I've measured a similar impulse response is the Quad ESL-63.)

Fig.3 Dunlavy SC-IV, impulse response on HF axis at 3m (5ms time window, 35kHz bandwidth).

Look at the SC-IV's step response in fig.4. Pretty ideal—the outputs of all the drive-units arrive at the microphone at pretty much the same time. This, by definition, is time coherence. As a result, the SC-IV is one of the only two loudspeakers I've encountered that can produce a good squarewave shape. (The other was, again, the Quad ESL-63.) And this was over a wide bandwidth, from 200Hz to 5kHz. Although the subjective effects of a loudspeaker featuring time-coherent behavior are not fully understood, my subjective impressions have been that such designs always feature superb imaging and soundstaging. The SC-IV is no exception."

Again, I have no idea if it's because of John Dunlavy paying attention to various critical measurements that I love the speaker's sound so much, or if the measurements simply confirm that John Dunlavy's design ideas had merit.

All I know is that enjoy the music coming from these speakers and that at the end of day, it is what matters most to me. It's my hope that everyone can have enjoyment from their music systems, no matter what equipment they may employ.

Best wishes to all,
Don

Heard both the SC V and SC III if in the sweet spot they sounded pretty right. I think they could have been even better with more attention to parts.

 

[acousticsguru]

Heard both the SC V and SC III if in the sweet spot they sounded pretty right. I think they could have been even better with more attention to parts.

"Parts" referring to crossover parts? Because if referring to drivers, it's likely they were chosen specifically for their "correctability" in a design like this, and as I like to call it, benign behavior.

Greetings from Switzerland, David.

 

[acousticsguru]

Just listen and judge for yourself. Whether active Albatros V (photo above used in good condition 7-8k€) or passive brigantin speaker~95db/ 1watt, for me they are the benchmark (4-way speaker) from that time and still are today.

Today it would probably cost as much as the big Wilson 1982 (35,000 DM), the effort was enormous back then. For me it's still in the top 3 of everything I've ever heard.

I remember these speakers, and yes, they sound good! Huge difference whether passive or active, because for the latter, once the acoustic centre of each individual driver is shifted into place for an assumed minimum distance (that can be calculated from the farthest center-to-center distance of drivers in a baffle), the limit for the overall in-phase behavior of the speaker are the drivers themselves. What happens with passive designs is the in-phase behavior of the drivers, even if the acoustic centre are properly time-aligned, is often sacrificed in order to make the crossover slopes sum unless the drivers are purpose-designed for the application. Very few speaker manufacturers do this, including for cost-no-object designs.

As @microstrip explains above, this is precisely what happens in a Wilson design: instead of aligning the acoustic centers of drivers that play in phase over a sufficiently wide range, users shift drivers to avoid crossover cancellations as best they can for their listening position, because these drivers don't play in phase. It defies logic, because there's no time alignment without in-phase behavior. As a matter of fact, one needs all three simultaneously: in-time, in-phase and flat frequency response for overall coherency. Can't isolate or "optimize" one at the cost of the other.

Greetings from Switzerland, David.

 

[Lee]

What makes you think so many audiophiles change gear with great regularity? I know plenty who don't. Maybe those who frequent forums such as this? I personally don't. It's a mere matter of finding something one really likes (and can afford). Of course there are people who are constantly on the lookout, eternally dissatisfied, but it's always seemed to me this has nothing to do with being a music lover, those people tend to be the exact same in other aspects of life. What I do consider an essential part of happiness is curiosity and the ability to learn. I do love to spend time with audiophile buddies, go to shows, hear new stuff. Having said that, at the end of the day, the basis of my buying decisions is not an itch, but relevance. Something would have to make me listen to music (and I mean attentively, I try to avoid background noise altogether) even more than the 20-25 hours per week I manage to get in, or with even less listening fatigue (that would be tough, even when I listen for 7 hours straight, those tend to be the days or nights into the wee hours when I'm tempted to put on yet another album). Are all differences we hear improvements? Relevant improvements? Much of what I'm hearing seem like side steps to me. To me, what you're touching on IS what I consider relevant and an improvement: what one enjoys on a daily basis, holds on to, and would not want to change is the very definition of "better".

Greetings from Switzerland, David.

Given that optimal setup leads to musical engagement, the lack of proper setup must contribute to frequent component changes.

 

[morricab]

"Parts" referring to crossover parts? Because if referring to drivers, it's likely they were chosen specifically for their "correctability" in a design like this, and as I like to call it, benign behavior.

Greetings from Switzerland, David.

Yes, and cabinetry was good but not SOTA.

 

[acousticsguru]

Given that optimal setup leads to musical engagement, the lack of proper setup must contribute to frequent component changes.

Excellent point! I’ve shared this story before, but I know at least one audiophile who uses a rectangular room twice as long as wide, bare concrete wall on one side, bottom to ceiling windows front and other side, bare concrete ceiling, ceramic tiles floor, and who can’t seem to find e.g. a DAC he doesn’t find bright, except, miraculously, they all sound good on his headphone setup.

Greetings from Switzerland, David.

 

[microstrip]

(...) As @microstrip explains above, this is precisely what happens in a Wilson design: instead of aligning the acoustic centers of drivers that play in phase over a sufficiently wide range, users shift drivers to avoid crossover cancellations as best they can for their listening position, because these drivers don't play in phase. It defies logic, because there's no time alignment without in-phase behavior. As a matter of fact, one needs all three simultaneously: in-time, in-phase and flat frequency response for overall coherency. Can't isolate or "optimize" one at the cost of the other.

Greetings from Switzerland, David.

Perhaps it defies logic, but the specific "time alignment" that Wilson Audio uses creates an extremely precise and powerful soundstage with good focus that is one thing what many listeners enjoy in sound reproduction. I have witnessed several times the effect of bringing the units to the proper setting as advised by Wilson tables and can assure it is really effective.

Please note that "time alignment" is a generic term that does not imply coherency or anything precise. And David Wilson never designed for flat measured frequency response.

Although I changed of speakers many times, along forty years I have always kept the ESL63 as my reference - I currently own two pairs. No speaker I have listened to has the same spatial information and accuracy. But with careful positioning and setup I have found that the Wilson Audio XLF's in my old room could be close for the music I listen mostly.

 

[microstrip]

(...) What I do consider an essential part of happiness is curiosity and the ability to learn. I do love to spend time with audiophile buddies, go to shows, hear new stuff. (...)

Greetings from Switzerland, David.

I share your words, although I go to shows mainly for the social part and information, I do not expect to hear great sound or listen properly in such environment. I can count with my fingers the few occasions when I listened to something I consider worth notice.

But how can we please curiosity and learn without trying and changing? I only bought new a few pieces of equipment - curiously the more expensive, ordered without trying them in my system.

 

[microstrip]

Not at all, it’s a fair comment, especially on this forum, as I have little doubt a disproportionate number of eternally dissatisfied audiophiles are gathered here, along of course with us others who are curious and keep informed on what’s new.

Greetings from Switzerland, David.

Although I can count a few people I know as eternally dissatisfied audiophiles, I count a lot more of eternally satisfied changing audiophiles among my audiophile friends and acquaintances. Some times we seem to forget this is an hobby, not a chore or job - except for manufacturers or dealers.

 

[DasguteOhr]

I remember these speakers, and yes, they sound good! Huge difference whether passive or active, because for the latter, once the acoustic centre of each individual driver is shifted into place for an assumed minimum distance (that can be calculated from the farthest center-to-center distance of drivers in a baffle), the limit for the overall in-phase behavior of the speaker are the drivers themselves. What happens with passive designs is the in-phase behavior of the drivers, even if the acoustic centre are properly time-aligned, is often sacrificed in order to make the crossover slopes sum unless the drivers are purpose-designed for the application. Very few speaker manufacturers do this, including for cost-no-object designs.

As @microstrip explains above, this is precisely what happens in a Wilson design: instead of aligning the acoustic centers of drivers that play in phase over a sufficiently wide range, users shift drivers to avoid crossover cancellations as best they can for their listening position, because these drivers don't play in phase. It defies logic, because there's no time alignment without in-phase behavior. As a matter of fact, one needs all three simultaneously: in-time, in-phase and flat frequency response for overall coherency. Can't isolate or "optimize" one at the cost of the other.

Greetings from Switzerland, David.

The only thing that ist diffrent the albatros have a active bass equalization it plays 10hz-12hz lower.
a check and refresh of the drivers, filters and amps is worth it costs ~3k€ (2014) in Brest at Cabasse. one must not forget that a lot has been done in e.g. capacitor technology. it will probably sound much better than it already did.

 

[acousticsguru]

I share your words, although I go to shows mainly for the social part and information, I do not expect to hear great sound or listen properly in such environment. I can count with my fingers the few occasions when I listened to something I consider worth notice.

But how can we please curiosity and learn without trying and changing? I only bought new a few pieces of equipment - curiously the more expensive, ordered without trying them in my system.

Visiting fellow audiophiles? I’m a firm believer in happiness to be something one needs to cherish and cultivate, so if as an audiophile one happens to enjoy oneself and be happy with what one’s got, that’s all one could possibly ask for: just put on another record!

In the meantime, I love spending weekends at audiophile buddies homes, listen to all new goodies they’ve accumulated, it’s cool, nothing wrong with it. It’s just that I spend so much time listening to music, I don’t want to take away from it remodeling my systems on a regular basis. Rolling tubes now and then is plenty enough change if I am in the mood for change.

The main thing is: there’s so much music I haven’t yet heard. Not just out there, but that I own. It’s as with fine wine, one keeps buying, yet has no plans of becoming an alcoholic, and we’ve all got only so much (or little) time.

Greetings from Switzerland, David.

 

[Holmz]

How?
Are the bits not coming off with zero bit errors?
What does the transport do good and bad to influence all that?

Hey @caesar any further clarification to post #1154?

 

[microstrip]

It's even worse: Not all who compare system sounds to live events can agree on what sounds real or not.

Known since long. Sound reproduction does not aim to a physical facsimile of real sound. When I go to a concert I completely forget about stereo systems.

In that context, I have also learned that some who are regularly exposed to live sound don't seem to have a reliable memory of it.

Surely. As soon as they do not agree with us we should immediately label them as non reliable listeners.

 

[Al M.]

Surely. As soon as they do not agree with us we should immediately label them as non reliable listeners.

It's a bit more complicated than that...

 

[Ducar]

Sony PCM F1 Digital Audio Converter

In 1978, when I reviewed Sony's first audiophile-type PCM-1 converter, I earned the undying scorn of a large segment of audiophilia by reporting that, on the basis of a rather short testing period (which did however include some live recording), I was unable to hear anything the matter with its...

www.stereophile.com

 

[Gregm]

Just listen and judge for yourself. Whether active Albatros V (photo above used in good condition 7-8k€) or passive brigantin speaker~95db/ 1watt, for me they are the benchmark (4-way speaker) from that time and still are today.

Today it would probably cost as much as the big Wilson 1982 (35,000 DM), the effort was enormous back then. For me it's still in the top 3 of everything I've ever heard.

I have a very fond memory of the Ambatros, stareting with the very first (I think) active model with tube amplification down to the V. I remember being astounded by the incredibly large sound, the naturalness, and the huge realistic soundstage of the older model. I had never heard anything like it before