Sensitive to what? The acoustic centres are the same (in decent designs) so that won't apply, neither cone will be resonating (in decent designs) so that won't apply, the radiation pattern through the crossover region will be the same (in decent designs), linear distortion will be negligible (in decent designs) and nonlinear distortion negligible (in good designs - bit trickier to achieve),... so what is there for the ear to be sensitive to?
A wide band driver will be resonating with an audibly uneven on- and off-axis frequency response through the "crossover" region and likely audible nonlinear distortion at reasonable SPLs. They won't sound the same but the case for the wideband driver seems to be pretty poor except if non-performance related factors like low price and possibly low complexity are included and heavily weighted.
If you wish to put forward "coherence" as a difference can you please define what it is in a scientific/technical manner so that it can be identified, measured, and understood by everyone in the same way. Not intending to have a dig or state that "coherence" doesn't exist but more to keep the discussion based around factors we can all hear and recognise.
Andy,
Fletcher -Munson curves.
The acoustics center are more often non coincident on Z axys in coaxials: the exception like Kef or the latest small diameter Tannoy (from some years ago, with a white cone) are just that: exception ime.
Some coax are very good engineered and can sound good too but they are not a panacea either there is always compromise.
'Coherence' exist as a defined parameter as Pano (iirc) once explained but it doesn't relate to what Dave want to point.
Fletcher -Munson curves.
The acoustics center are more often non coincident on Z axys in coaxials: the exception like Kef or the latest small diameter Tannoy (from some years ago, with a white cone) are just that: exception ime.
Some coax are very good engineered and can sound good too but they are not a panacea either there is always compromise.
'Coherence' exist as a defined parameter as Pano (iirc) once explained but it doesn't relate to what Dave want to point.
Which studyes? And why headphones would change anything?
Picowallspeaker, i totally get you've got your own pov on thing and question evidence but at one point it doesn't make any sense to question some things including basis accepted as facts for almost a century... or you have to display some solid demonstration to counteracts the basis of science...
i mean there was one member in here which believed only on current in Ohm's law... doesn't make any sense, kind of flatearther. It can't be judged seriously.
Picowallspeaker, i totally get you've got your own pov on thing and question evidence but at one point it doesn't make any sense to question some things including basis accepted as facts for almost a century... or you have to display some solid demonstration to counteracts the basis of science...
i mean there was one member in here which believed only on current in Ohm's law... doesn't make any sense, kind of flatearther. It can't be judged seriously.
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And what does it have to do with the fact our evolution made us sensible to some frequency range ( which are coincident to the one our babies produce when they have a need...) for species protection purpose??? And it can explain why we are less sensitive to some arrivng direction than others ( less chance a predator was located above us) why we have cocktail party effect ( reconstruction from partial signal help identify predator on background noise) etc,etc,...
Sorry but it doesn't make sense to me... At least presented as such. Explain a bit more than a laconic sentence and maybe there could be a sense to be found but as is...?
Sorry but it doesn't make sense to me... At least presented as such. Explain a bit more than a laconic sentence and maybe there could be a sense to be found but as is...?
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That was easy: with the headphones you negate the space where the sound ( not yet...sound) evolves, prapagates, extinguishes.
All the previous talks about directivity, drivers & systems would simply not exist without the space around ( we call it 'room')
Because there is no inner space between your headphone driver and tympany? Common man, next argument is 20Hz cannot be produced in that space because full wavelength cannot 'evolve'?!!!
Our hears are not contact microphone ( not totally as we listen through our body/ bones (even eyes!) for some frequency range).
Please go back study the thing you don't grab it yet fully.
Our hears are not contact microphone ( not totally as we listen through our body/ bones (even eyes!) for some frequency range).
Please go back study the thing you don't grab it yet fully.
All that the Fletcher Munsen curve shows us is that the ear is more sensitive to the 2 kHz to 5 kHz frequencies and that's where most tweeters cross.
We could talk about our ability to perceive phase next, lots of conflicting views on that. In most (untreated) rooms it will be a non issue (as in: you won't perceive phase rotations in such an environment), but I do not believe that testing phase should be done with headphones. We listen with more than our ears alone.
2 KHz would pretty much be a blind spot (due to interaural cross talk) in traditional stereo triangles though, a coax could cross there.
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I think KEF is one of the few that can get a pretty decent on-axis as well as off-axis response of a coax.
The majority of other coax drivers have a extremely irregular frequency response, often with all kinds of issues.
Which can do more harm than good in sense of audibility.
But anyway, the whole concept of a coax leans on the fact that one can get a good off-axis response on the vertical axis.
Which is debatable from our hearing point of view, but also debatable from a acoustics point of view because how close the floor and ceiling are. Meaning that there won't be much left from that perfect vertical off-axis response anyway.
In general a perfect off-axis response (spinoramas) seems the new thing people pixel peep on.
Not taking the absorption of the room in mind or lack there off, depending on the frequency we are talking about.
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Let's say between 1khz and 2khz is not a bad zone to locate a filter: from our head shape the 'gray zone' for our ability to locate sound from ITD to level difference is located there too.
I wonder if it doesn't play a part too in the fact 'coax' are said to gives a nice rendering of soundstage.
Yes there will be, it will follow the balance of the direct sound and that's way more comfortable than to have it deviate in balance.
I still like to have phase linearity through the crossover, call it personal preference but it kind of makes it hard not to pay attention. The direct sound becomes attention grabbing. Easier to focus on.
That totally depends on the absorption and reflection characteristics of that surface.
Which is not very constant for most materials.
Ignoring any physical obstructions.
So it most definitely won't follow "the balance" of the direct sound.
This is in fact one of the reason why there are very specialized acoustic engineering companies out there, to get that whole sound reflection and absorption right.
The fundamental reason why someone wants to get an even distribution in the room.
There is nothing more disturbing than having a perfect good linear directivity, but being totally messed up by the fact that certain surfaces accentuate a certain frequency band. That sounds absolutely awful.
In same cases as bad as being destructive even with just simple speech.
I'm not advocating phase doesn't mater in the whole picture Wesayso, what i'm saying is in that range we loose focus on it and so the brain is more easily tricked and so if an issue have to be induced it makes sense to locate it here.
Anyway i learned a timbre is a relationship between an infinity of sinus of given frequency/amplitude ( envelope)/phase. Change one of this parameter and you introduce distortion.
So we are in agreement.
Anyway i learned a timbre is a relationship between an infinity of sinus of given frequency/amplitude ( envelope)/phase. Change one of this parameter and you introduce distortion.
So we are in agreement.
I don't know if it can do more harm than good ( the irregularity) in sense of audibility? In fine i think it is preference related.
The Kef drivers i have sounds and measure good for sure, but my initial listening session tells me they lack on some aspect i'm used to.
In that some bigger diameter coax plagued by other disease would have maybe gave me something more to my preference? I don't dislike them but they miss in dynamic rendering vs a 12" or 15" in my view. Xover them high enough and using other drivers lowers might help though... not still sure.
About good vertical axis i think it's the most important factor: in a typical room those are the lowest dimension and as such the one which will gives the more harmfull ER.
In the control room built i've been involved acousticians always treat ceiling first with absorption/diffusion/reflection -thanks to cloud (but the fact mixing desks are big reflector doesn't help either and usually makes thing worse than a domestic situation) before even looking to anything else.
So true, the worst being wide directivity loudspeakers ime.
That said even horn with narrow directivity can be very disturbing about it, i heard some creating kind of 'ghost' image on narrow range freq. Very weird feeling.
Dome drivers are not immune to similar problems. Soft domes will also flex with a tendency to resonate at certain frequencies. A standard fix for this is reducing the Q (I'm talking about high frequencies, not T/S parameters) with resistive absorption. The air is excellent for this, but only provides a small mechanical load and the rest has to be done with soft polymers, which tend to be non-linear. So the bigger surface area of a wideband driver should help bring the amount of displacement (and hence modulation) down.
Notice how by the time the vibrations from a small voice coil in the middle of a cone spread out to the surround, the air should have already absorbed part of the energy. OTOH with domes the force from the VC is immediately divided between the dome and the surround, and the dome then vibrates with the left-over energy, which is kind-of backwards.
Ring radiators fix issues with waves producing a peak in the middle, but then it's basically all flex and no rigid materials.