John Atkinson's of Stereophile Talks About Measurements

[Snarfie]

I bought some months ago some Vandersteen Model 1 speakers. After some moving around an using room correction i was impressed with the sound staging/imaging of the Vandies. My old speakers quite good sounding JK Optima 3 speakers could not compete regarding sound staging/imaging. It is staging/imaging that i find important because at live recordings you could better hear the interaction between the band members and the surrounding acoustics of the venue they perform in if recorded correctly. Now for mine an possible others understanding Atkinson explains the correlation for good sound coming out of speakers minute 3:45 First order cross overs played an important roll to get a flat response an all difficult issues to get them right. He mentions that for instance Richard Vandersteen is one of the view who handled the known issues regarding first order cross overs correctly. Further more Atkinson stated that todays speakers designs don't pay attention/ignoring first order cross overs probably because it is to difficult i guess. So the question is there any correlation between sound staging/imaging an correct used first order cross overs?

 

[SIY]

Not that I have ever observed.

 

[Snarfie]

Not that I have ever observed.

At minute 15:10 Atkinsons explains what he observes (an we all do probably) if you hear a speakers system reproducing sound staging/imaging. It is as a open window. This is exactly as I experience with the Vandies if i compare them with other speakers like the JK Optima 3. He also recommends to do a pink noise test that can reveal if a speaker system is capable to reproduce any Sound staging/imaging correctly. Think this is quite helpfull if you desire speakers with staging/imaging capabilities.

 

[SIY]

At minute 15:10 Atkinsons explains what he observes (an we all do probably) if you hear a speakers system reproducing sound staging/imaging. It is as a open window. This is exactly as I experience with the Vandies if i compare them with other speakers like the JK Optima 3. He also recommends to do pink noise test that can reveal if a speaker system is capable to reproduce any Sound staging/imaging correctly.

But assigning cause to first order crossovers (which are rarely first order) does not follow.

 

[Snarfie]

But assigning cause to first order crossovers (which are rarely first order) does not follow.

Thats correct he does not make the correlation with first order cross overs would be interesting to know if there any.

 

[xr100]

First order cross overs played an important roll to get a flat response an all difficult issues to get them right. He mentions that for instance Richard Vandersteen is one of the view who handled the known issues regarding first order cross overs correctly.

Are they actually "first-order" crossovers acoustically?

 

[Snarfie]

Are they actually "first-order" crossovers acoustically?

i'm unfortunly (or fortunly) not an tecnical expert.

 

[xr100]

i'm unfortunly not an tecnical expert.

The electrical response of the crossover may well be first-order but what happens is that it combines with the loudspeaker's response.

For example, if we take a "random" 1" dome tweeter (Seas), then the published frequency response plot shows that it rolls off below 1kHz or so:

So, considering the (more straightforward) case of an analogue active crossover, a first-order high pass filter will roll-off at 6dB/octave below the chosen frequency, say 2kHz. This electrical signal is fed to the amplifier, and in turn, to the tweeter.

Ultimately, without any crossover, the tweeter will roll-off. It is certainly not going to be flat to 20Hz (!), so at some point the tweeter's response and the active crossover's response combine, at 1kHz or so in this case.

The tweeter itself MUST have a phase response as implied by its frequency response; and, as with the frequency response, this will in turn combine with the active crossover's ("electrical") phase response. The combined frequency and phase responses can be measured acoustically.

Hope that makes sense?

 

[DonH56]

Lacking by comparison?

Haven't used REW enough to say. Different. But REW is free, and even if you add in $1k~$2k for mic and PC doesn't hit the cost of one of our RF/mW spectrum analyzers (something like $250k last I checked).

 

[xr100]

PC doesn't hit the cost of one of our RF/mW spectrum analyzers (something like $250k last I checked).

 

[SIY]

Thats correct he does not make the correlation with first order cross overs would be interesting to know if there any.

There isn't. Actual 1st order is almost non-existent, has terrible lobing issues, generally poor distortion through the crossover region, and is only "phase coherent" at one location. To get anything even vaguely worthwhile requires 4 or more drivers.

The two best imaging speakers I've ever had (and I've had a LOT of speakers over the years) were a minimonitor with 8th order slopes, my current "big boy" 4 way speakers with LR4 from bass to midbass, B2 from midbass to midrange, and B3 from midrange to tweeter, and some homemade speakers loosely based on the Dynaudio DA500 that were 5 way with first order electrical (and a mixed bag of acoustical) crossovers.

See a correlation? Me neither.

 

[Snarfie]

There isn't. Actual 1st order is almost non-existent, has terrible lobing issues, generally poor distortion through the crossover region, and is only "phase coherent" at one location. To get anything even vaguely worthwhile requires 4 or more drivers.

The two best imaging speakers I've ever had (and I've had a LOT of speakers over the years) were a minimonitor with 8th order slopes, my current "big boy" 4 way speakers with LR4 from bass to midbass, B2 from midbass to midrange, and B3 from midrange to tweeter, and some homemade speakers loosely based on the Dynaudio DA500 that were 5 way with first order electrical (and a mixed bag of acoustical) crossovers.

See a correlation? Me neither.

Found this article about phase coherent speaker design as Thiel audio called it speaker some years ago.


https://hometheaterreview.com/first-order-crossovers-panacea-or-problem/

A quote explains in this article that first order crossovers are quite important regarding imaging. Question however is are there other crossovers or other designs that do the same job regarding imaging or is this imaging a specific advantage for the combination (possible correlation) of first order cross overs an a baffled setup of drivers. My Vandersteens speaker have also a baffled driver setup using first order crossovers an i had also many speakers listened to in 50 years time only the Vandersteens got the job (the best) done compared with all other speakers. Must say one thing about the Vandersteens it took time to get the best results. You don't place this speakers easy/conveniently. But when you do (an in my case using room correction badly needed) the listening window is wide open combined with an great clarity i rarly encounterd.

"The benefit of a first-order crossover is that it maintains the phase of the original signal, as long as the speaker that it's used in has the acoustic centers of the drivers aligned in the vertical plane, often through the use of a sloping front baffle. As long as your head is positioned so that your ears are equidistant from all the drivers, the phase of the direct sound that first reaches your ears shouldn't vary by more than a few degrees. That's why THIEL and other manufacturers refer to this as a phase-coherent design.

How does this affect the sound you hear? I've reviewed perhaps 10 THIEL speakers since the early 1990s, as well as several other phase-coherent designs. To my ears, the benefit of phase-coherent design is that you get a more enveloping sound stage, more like what you'd expect to hear from a panel speaker such as a MartinLogan or Magnepan--but with more precise imaging than a dipolar panel speaker can produce. It's a great sound, one I strongly recommend every audio enthusiast check out for themselves in a well-designed dealer showroom or at an audio show."

This how it looks like at my mancave (still under construction). When i place the Vandersteens just 10 a 15 cm back the imaging an lows get less.

An this is how they measure.

 

[SIY]

I think highly of Brent, but I think he’s all wet here. And hasn’t done some of the basic experiments needed to support his claim.

 

[Snarfie]

I think highly of Brent, but I think he’s all wet here. And hasn’t done some of the basic experiments needed to support his claim.

Yesterday i put the question forward to Richard Vandersteen if he wants to elobarate about possible correlation between firts order crossovers an staging/imaging. Looking forward to his respons (if he will respond) I guess if he responded he will make the correlation between baffeld setup of drivers in combination with first order cross overs. Will keep you posted about his (possible) remarks.

 

[Snarfie]

Yesterday i put the question forward to Richard Vandersteen if he wants to elobarate about possible correlation between firts order crossovers an staging/imaging. Looking forward to his respons (if he will respond) I guess if he responded he will make the correlation between baffeld setup of drivers in combination with first order cross overs. Will keep you posted about his (possible) remarks.

His answer is I quote: "This is a complex subject and the simple answer is that many parameters are important for this.
You should read my “Design and Application” under white papers in Resources."

Must say didn't expected an answer in general or this fast. Must say he really cares about his customers.
So basically reading his paper “Design and Application under white papers in resources" could/will explain what is needed (baffled driver setup any order of crossovers or others correlations) to design a stable staging/imaging speaker system.

Maybe there are some forum members who know about his paper or read it.

 

[dorirod]

[QUOTE="We are capable of adapting to a wide range of sound signatures. What I'm finding as I perform this little exercise with EQ on my various gear is that initially a neutral sound signature can seem a little bland...but after a very brief period for your ears to acclimatize it becomes magical."[/QUOTE]

Hmm, actually, I think what your anecdote says is that you liked the distorted sound just as much as the neutral/corrected sound. You only preferred the neutral sound once you compared it to the distorted one after having had a prolonged exposure to it. If your brain constantly adapts as you say, you'd have no problem listening to distorted sound. Is the neutral sound still magical after a few weeks? How do you know (short of exposing yourself to the distorted sound once in a while). The only nagging feeling would come from knowing that it's distorted (or having someone else point out that your sound is distorted). In other words, ignorance is bliss (not to mention cheap)!

 

[Krunok]

[QUOTE="We are capable of adapting to a wide range of sound signatures. What I'm finding as I perform this little exercise with EQ on my various gear is that initially a neutral sound signature can seem a little bland...but after a very brief period for your ears to acclimatize it becomes magical."

Hmm, actually, I think what your anecdote says is that you liked the distorted sound just as much as the neutral/corrected sound. You only preferred the neutral sound once you compared it to the distorted one after having had a prolonged exposure to it. If your brain constantly adapts as you say, you'd have no problem listening to distorted sound. Is the neutral sound still magical after a few weeks? How do you know (short of exposing yourself to the distorted sound once in a while). The only nagging feeling would come from knowing that it's distorted (or having someone else point out that your sound is distorted). In other words, ignorance is bliss (not to mention cheap)![/QUOTE]

Not so. Neutral (corrected) sound always sounds good and with non-corrected boomy sound bass notes are always mixed with the dissapearing ones as difference between them is typically 15-20dB. You only need to hear true neutral sound once and it will never cross your mind to reurn back. You will also within a few seconds recognise noc-corrected sound at your friends house, dealers demo room etc. Which comes to no surprise - remember those 15-20dB variations between tones?

 

[dorirod]

Ah, that made it quick to make but boy, who has heard of Indian curry being about dumping spices in a dish and just warming it?

Just Varm it Up

 

[Sgt. Ear Ache]

Hmm, actually, I think what your anecdote says is that you liked the distorted sound just as much as the neutral/corrected sound. You only preferred the neutral sound once you compared it to the distorted one after having had a prolonged exposure to it. If your brain constantly adapts as you say, you'd have no problem listening to distorted sound. Is the neutral sound still magical after a few weeks? How do you know (short of exposing yourself to the distorted sound once in a while). The only nagging feeling would come from knowing that it's distorted (or having someone else point out that your sound is distorted). In other words, ignorance is bliss (not to mention cheap)!

Yes, that's sort of what I was saying. Ignorance is bliss, but I'm not ignorant now, and there's a "special" bliss to be found in neutrality. I'm now the guy pointing out the distortion. The neutral sound remains magical...because I'm finding it to be more revealing, more accurate and more enjoyable. The ultimate point was that we can choose what to become accustomed to, and it might as well be neutral since that is the best way to experience the recording in it's fullest form. When something is emphasized, other things are by definition de-emphasized. When things get de-emphasized, they also can get lost.

 

[Hugo9000]

Oh, dear, the notorious spelling scold couldn't manage to get the name of a legend of television, film, theatre, recordings, etc. with multiple hit shows and countless awards (Grammy, Peabody, Emmy, and more) right?

Time passes. I eat an apple. The plane's TV screens show Carole [sic] Burnett being professionally funny.

Between 1986 and 2020 and across two magazines, he still can't get her name right? Yet it's important to patrol audio sites to correct people for their casual misspelling on the internet of the name of a minor columnist at a very minor magazine. LOL

(Is "professionally funny" supposed to be a clever dig at her expense? The article is sprinkled with his own attempts at humor, so it's hard to tell. Perhaps he meant to convey that she's a professional comedian and actually is funny, while he's an amateur, and is not.)