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What exactly is "imaging" ?

Thanks for your reflections John and Tony. My experience comes from once modelling in the speaker/room interaction program previously at cara.de. I soon discovered that one get the most even low frequency response when both (only one) speaker and the listener is 1/3 from their nearest walls. But, only with one speaker (mono).
So I moved speakers around and came to a decently flat response with the listener 1/3 into the room and the speakers (two now, stereo) at least 1/5 or 1/7 from the walls. An as asymmetrical setup as nearly is possible! So, after shuffling of physical speakers and some measurements, how did it sound?
Yes, the center image was a bit vague, as expected. But what I discovered, a bit surprising at first, was that I heard more of the recorded ambience and less of the listening rooms 'sound' (thankfully). My explanation is that the reflected sound of the various walls reaches the listener at different times and with different phase, making it sounding considerably more diffuse. That could be reached with diffuser panels, I guess, but I don't have any.

Now, with tinnitus, my hearing is considerably worse in one ear, so the central image isn't there anyway.
 
As stated upthread I’d personally argue narrow dispersion is an advantage for most audiophiles as you get the sound before the room reflection. A lot of the best speakers from a imaging/soundstaging perspective are ESLs, horns etc IME. If you have an uneven/asymmetrical room the very last thing you want to be doing is bouncing sound off all the walls if you can aim it at your ears first. I suspect Toole resides more in the home cinema/pro install market, I certainly don’t hang off his every word for serious 2 channel home audio.

Or loudspeakers very near to the rear wall with damping around, like Stig Carlsson's later designs (OA50, OA51, OA52 * and now sold under the Larsen brand), this maximizes the time for the first reflection, usually from the ceiling, to reach the listener after the direct sound. It's very effective and basically, with the right program material, takes away the rear wall and replaces it with a very convincing illusion of the sound from the recorded venue.

* But not the older OA5 - OA2212 with a multitude of cheap paper tweeters scattered around, they did exactly the opposite, created an early diffuse sound.
 
Personally I can't deal with horn speakers for any length of time. Even if they impress otherwise, I end up hearing some kind of "horn sound" (which may be due to narrow dispersion) that I find disturbing, eventually! Each to their own.
 
As stated upthread I’d personally argue narrow dispersion is an advantage for most audiophiles as you get the sound before the room reflection. A lot of the best speakers from a imaging/soundstaging perspective are ESLs, horns etc

I'd not linked that before in my 25 years of speaker building,
I use a quite a directional mid driver, and the drivers below have been made directional with the use of 'loaded' front port.
With the speakers toed in they really sound the same, regardless of which room they are used.
My goal has been low bass cancellation in open baffle.
Interesting observation Tony..
 
Interesting observation Tony..

For me it is just an observation, but Paul Klipsch put some real research work into it in the 40s and 50s when developing the Klipschorn. It is worth hunting down his old white papers and ‘Dope From Hope’ writings which do exist online somewhere (they used to be linked on the Klipsch forum somewhere, but I couldn’t find them when I looked earlier in this thread).

He argued very convincingly for both corner positioning and high directivity/controlled dispersion and how that was the best from a acoustic perspective. I don’t have the experience with corner horns (beyond sticking my old La Scalas in alcoves) so have no subjective opinion there, but all the speakers I really like seem to control vertical and horizontal dispersion in the mid & treble to quite some degree.

Even the little LS3/5A is doing some stuff with the metal grille over the T27 and heavy surrounding felt. The BBC certainly considered dispersion even if it may be a non-deliberate effect with Tannoys, ESLs etc. Obviously ESLs play by a whole other rule book being dipoles, but they are certainly very narrow dispersion and actually cancel/null at the sides.
 
For me it is just an observation, but Paul Klipsch put some real research work into it in the 40s and 50s when developing the Klipschorn. It is worth hunting down his old white papers and ‘Dope From Hope’ writings which do exist online somewhere (they used to be linked on the Klipsch forum somewhere, but I couldn’t find them when I looked earlier in this thread).

He argued very convincingly for both corner positioning and high directivity/controlled dispersion and how that was the best from a acoustic perspective. I don’t have the experience with corner horns (beyond sticking my old La Scalas in alcoves) so have no subjective opinion there, but all the speakers I really like seem to control vertical and horizontal dispersion in the mid & treble to quite some degree.

Even the little LS3/5A is doing some stuff with the metal grille over the T27 and heavy surrounding felt. The BBC certainly considered dispersion even if it may be a non-deliberate effect with Tannoys, ESLs etc. Obviously ESLs play by a whole other rule book being dipoles, but they are certainly very narrow dispersion and actually cancel/null at the sides.

Both the Kef Blade and the D&D 8c are able to produce narrow and smooth directivity without using “horns” (they do use waveguides)
And they are able to control directivity to a lot lower in frequency than non-corner loaded Klipschs.

Toole’s research, also his preference, seems to indicate that more people prefer wider directivity/ more room interaction and little to no early reflection zone treatment
Years of observing audiophiles in forums make me believe that this is indeed the case
 
Toole’s research, also his preference, seems to indicate that more people prefer wider directivity/ more room interaction and little to no early reflection zone treatment
Years of observing audiophiles in forums make me believe that this is indeed the case
Is this conscious preference or an unconscious one? i.e. have listeners/audiophiles been exposed to both approaches and decided that they prefer wide directivity / more room interaction, or have they only experienced the latter? I can only speak for myself here, but I was pretty much oblivious to the extent and complexity of room acoustics until my mid-20s. I obviously knew that an empty room with flat, hard surfaces generated lots of reflections that were detrimental to accurate sound reproduction, but I had no idea at that time that different speaker designs affected this to different degrees.
 
I quoted Toole's explanation:

The stereo phantom center will suffer from a significant dip in the spectrum around 2 kHz because the sound from both loudspeakers reaches both ears at different times. This interaural crosstalk cancellation is the first dip in an acoustical interference comb filter as explained in Figure 7.2.
Just catching up with this thread, to clear the confusion the graphs show a 2khz dip for one ear and as each source is incident upon either side of the head each ear will suffer the same L/R, R/L delay/cancellation., ie the left speaker output hits the left ear first and right ear second, the right speaker output hits right ear first left ear second.
Klipsch, Briggs, the BBC, Tannoy etc understood the physics but were limited to the technology available for measurement, Tannoy were concerned/understood the dispersion characteristics/directivity of the DC , earliest I can find is mid 60's specs that includes the 'polar distribution' spec (60 deg included angle -4dB @10khz) and reference to the Dual Concentric not suffering the 'spacial distribution defects' of conventional(2 way) horns.Tannoys GRF/Autograph compound horns also display a thorough understanding/exploitation of dispersion/directivity.
 
Is this conscious preference or an unconscious one? i.e. have listeners/audiophiles been exposed to both approaches and decided that they prefer wide directivity / more room interaction, or have they only experienced the latter? I can only speak for myself here, but I was pretty much oblivious to the extent and complexity of room acoustics until my mid-20s. I obviously knew that an empty room with flat, hard surfaces generated lots of reflections that were detrimental to accurate sound reproduction, but I had no idea at that time that different speaker designs affected this to different degrees.
The euphonic effects are well know: increased envelopment and wider phantom images
The downsides too, as well as the requirements if a neutral balance is to be produced at the listening spot

Here and in other aspects of reproduction most audiophiles seem to prefer euphony over accuracy
 
Toole’s research, also his preference, seems to indicate that more people prefer wider directivity/ more room interaction and little to no early reflection zone treatment
Years of observing audiophiles in forums make me believe that this is indeed the case

That’s not my reading at all. To my understanding most audiophiles optimise their system for the hot-seat and don’t really care about off-axis. I agree some seem to like a more live sound, but many of us never have. I’ve certainly always gone for a well damped and controlled room even if I do it ‘old-school’ (live end/dead end etc) rather than pay out for fancy bespoke treatments. From my perspective one reason I have comparatively little interest in Toole’s research is it just doesn’t seem that relevant to folk like me who optimise for that single listening seat.

PS I’m always amazed when I see rooms without carpet etc. I’d not want to listen there.
 
Here and in other aspects of reproduction most audiophiles seem to prefer euphony over accuracy

I don’t think you are either understanding Toole or “most audiophiles”, let alone “accuracy”, or indeed “to what”.
 
That’s not my reading at all. To my understanding most audiophiles optimise their system for the hot-seat and don’t really care about off-axis. I agree some seem to like a more live sound, but many of us never have. I’ve certainly always gone for a well damped and controlled room even if I do it ‘old-school’ (live end/dead end etc) rather than pay out for fancy bespoke treatments. From my perspective one reason I have comparatively little interest in Toole’s research is it just doesn’t seem that relevant to folk like me who optimise for that single listening seat.

Audiophiles don’t care about off-axis but their speaker and positioning choices, the amount of toe-in or the untreated rooms do show what kind of presentation they prefer.

I think people like you and I are a minority in terms of preference for narrow directivity

I am not a Toole fanboy but he’s a far better reference than the joke Fremer or old Dudley
 
That’s not my reading at all. To my understanding most audiophiles optimise their system for the hot-seat and don’t really care about off-axis. I agree some seem to like a more live sound, but many of us never have. I’ve certainly always gone for a well damped and controlled room even if I do it ‘old-school’ (live end/dead end etc) rather than pay out for fancy bespoke treatments. From my perspective one reason I have comparatively little interest in Toole’s research is it just doesn’t seem that relevant to folk like me who optimise for that single listening seat.

PS I’m always amazed when I see rooms without carpet etc. I’d not want to listen there.
If you have a look at this link you will see a picture of Toole’s own listening room. Very much organised for AV, not music.
 
I don’t think you are either understanding Toole or “most audiophiles”, let alone “accuracy”, or indeed “to what”.

That is your opinion.
You have a tremendous parti pris against Toole. Have you actually read his book?

In audio the only accuracy possible is to the signal.
Most audiophiles are people like you and me and others at PFM, HFWW, CA, ASR, etc
 
I am not a Toole fanboy but he’s a far better reference than the joke Fremer or old Dudley

I don’t agree at all. Art Dudley represents the closest to my own approach to audio I’ve ever read, I have huge respect for him. Michael Fremer is someone I have a lot of time for as he does much good in the industry even if I have little in common with his audio tastes.

If you have a look at this link you will see a picture of Toole’s own listening room. Very much organised for AV, not music.

LOL, that’s *exactly* my mental image of what I thought he was selling! We are clearly at absolute polar opposites in the audio world, which comes as no huge surprise. I can pretty much guarantee I would not enjoy listening to two channel audio at all on that system. I’m trying to imagine just how bad something like Bill Evans Live At The Village Vanguard or a Bartok string quartet would sound at that distance from those upside-down multi-unit Revels and subs. Ugh! Just no! Give me one fairly nearfield pair of ESLs, Tannoys or LS3/5As every time! It probably sounds great on Godzilla or Aliens though.
 
He argued very convincingly for both corner positioning and high directivity/controlled dispersion and how that was the best from a acoustic perspective. I don’t have the experience with corner horns (beyond sticking my old La Scalas in alcoves) so have no subjective opinion there, but all the speakers I really like seem to control vertical and horizontal dispersion in the mid & treble to quite some degree.
I've not really had much to do with klipsch speakers, and never followed his research.. which is maybe something I rectify.
My early days where spent researching briggs work, I don't even think about using drivers that ain't 99db +, as to me the best amps are usually sub 10 watts, and in my case between 1 and 5 watts.
I try and stay clear of most writers opinions.
I've got to know many of the internet experts, it's often quite a shock when you hear how their kit sounds.
My experence is that not many people actually know what the recipe is to make a system that reproduces in a lifelike way, let alone those who write about what it might be.
 
My early days where spent researching briggs work…

I have huge respect for his work and have most of his books plus the more recent ‘A Pair Of Wharfedales’ biography. I even have a partly rebuilt single SFB/3 sitting on the landing upstairs. Still not heard it yet (too heavy to safely move alone, I nearly killed myself getting it up there!). I’d love to hear the huge brick corner speakers he advocated. It is a huge shame that the surrounds have failed catastrophically on so many Briggs-era Wharfedale speakers, it makes hearing first hand what he had in mind very hard, e.g. when I do eventually fire up the SFB/3 I know it won’t be ‘right’ as too many liberties were taken just to get the strange drivers to work again at all, just too many unknowns in their construction.

Paul Klipsch is just as fascinating to read as Briggs. Between them and Peter Walker most of what we know today is covered.
 
That is your opinion.
You have a tremendous parti pris against Toole. Have you actually read his book?

In audio the only accuracy possible is to the signal.
Most audiophiles are people like you and me and others at PFM, HFWW, CA, ASR, etc
Personally I would give anyone who follows wigwam, computer audiophile and especially ASR a very wide berth.

I wish I was as sure about one thing as Tuga seems to be about everything
 
Klipsch, Briggs, the BBC, Tannoy etc understood the physics but were limited to the technology available for measurement, Tannoy were concerned/understood the dispersion characteristics/directivity of the DC , earliest I can find is mid 60's specs that includes the 'polar distribution' spec (60 deg included angle -4dB @10khz) and reference to the Dual Concentric not suffering the 'spacial distribution defects' of conventional(2 way) horns.Tannoys GRF/Autograph compound horns also display a thorough understanding/exploitation of dispersion/directivity.

All the engineers and manufacturers you mentioned were at the forefront in the day but things have move on a bit.

I can agree that since speakers are now made small and narrow the potential in regard to low end performance and max SPL has been reduced but in overall terms XXI century speakers are potentially able to transducer the signal far more accurately and off-axis/directivity is now an important goal to far more manufacturers.
 
Personally I would give anyone who follows wigwam, computer audiophile and especially ASR a very wide berth.

I wish I was as sure about one thing as Tuga seems to be about everything

You’re part of an even smaller minority, that of people who enjoy omnidirectional speakers
 


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