What is your material on the ceiling? And propably 99% of all ceilings in homes?
It's a hard surface. In Europe a little harder as in USA but over all they are broadband reflective.
Floors? Hard or carpet - so everything under 5kHz gets reflected.
So these reflections are 100% in your listening sauce you experience in a living room - pretty straight.
@wesayso
So no - it will not follow the balance of the direct sound in a typical living room.
Did you ever experienced a good studio room with no ceiling reflection? Or installed a cloud and listened before and after?
The more I listen and compare over the years ... the more I prefer speaker with controlled directivity. Depending on the usecase wide or more narrow - but always even directivity.
Get a controlled Waveguide and standard HiFi like Speaker and go to different rooms. Listen. And then let's talk again.
(I did that with KH120 and Adam A7. Easy choice.)
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.
Perhaps but compensating in the crossover will align the soundwaves in time which is what matters. It is not an issue unless the crossover is crippled by being passive and unable to accurately delay in time.
As I was saying earlier there is compromise where limits lie relative to each other but if a speaker is designed to have a clean operating region (negligible linear and nonlinear distortion at sufficient SPL with desired radiation pattern) there is no practical compromise within this region. Of course, most speakers are not designed to have a clean operating region and many here don't think in these terms. As always, there is no correct directivity only relatively good and poor ones for a given room and source so there is obviously no question of practically perfect speakers in the way there is for most electronic audio hardware.
I have asked regularly for many years what "coherence" is from wideband enthusiasts. I have even stood next to such enthusiasts in front of a wideband speaker and asked them to point it out to me without success. I have had some success working out what, for example, valve enthusiasts are likely picking up on but I have so far been defeated when it comes to wideband driver enthusiasts. If you have a reference that addresses this I would be grateful but it needs to be what wideband driver enthusiasts are referring to rather than something else.
Walls shouldn't be too resonant at higher frequencies. They may roll off, but as long as it's smooth that's not bad. What I'd be more concerned about is polar inconsistency of a coax introducing this issue.
Aligning phase will affect the soundwaves. While time bears a relationship to phase, time does not change the wavefront per se.
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Sure it does.
And for the one which don't see the potential issue you can see it clearly there - but unlike what is written on the graph any amount of eq won't cure the issue, but allpass cells will, exactly what Tannoy did with the active version:
https://www.audiosciencereview.com/forum/index.php?threads/tannoy-system-600-speaker-review.11919/
This is the difference between hifi and pro monitors ime. The later having this clean operating region defined when done right ( not all pro stuff are good).
I can't answer. I'm still scratching my head about it. I know i like small widerangers for what they does. I think it is related to no electrical filter and the way directivity behave, (we are used to it).
That said it might be something else i'm not sensitive to. After all we don't listen to the same things and it might be something i didn't have heard or felt.
Maybe this is something related to time domain but there is no study i know of comparing wideband/multiway under this view angle. And given there is WAW and they bring benifits if something happen it must be in the mid/high.
Quite a bit of text as a rebuttal, but let me ask a simple question:
What speaker would have a better shot at it, a speaker with an even distribution or a speaker with obvious holes.
Most people don't even want to mess with room treatment.
Even though I did not use any "special acoustic engineering companies" myself, I was perfectly able to balance my direct sound and room reply in my own room.
You make it harder than it needs to be, the tools and knowledge are available to us all these days, if you're willing to actually look for it and spend the time to gain the knowledge.
Can you provide examples that don’t need DSP for aligning in time? I have yet to see any.
Woofer Assiste Wideband.
dave
I don't understand this comment and suspect we may have wires crossed. I was referring to shifting the wavefront from the tweeter and midrange differently w.r.t. time so that they sum precisely as required at the listening position. Removing the need to physically align drivers is one of the advantages of a modern active crossover compared to a passive. Of course the signal processing will also change the phase and magnitude differently with frequency to compensate for linear distortion and achieve the desired directivity through the crossover region.
I have worked with impulse measurements as part of my day job for many decades. I rather suspect that most wideband enthusiasts bringing up "coherence" are non-technical and a bit vague about the information contained in an impulse response and how it relates to other information like frequency response. Fair enough we are not all engineers but it does rather suggest their understanding of "coherence" is unlikely to be technical one (but can hopefully be mapped to something technical).
Having said that, what would you suggest is contained in an impulse response that can be used to quantify "coherence".
I mean this as supportive, not argumentative....
Here's my definition of a "coherent sound" with respect to an impulse....
as close as you can get to a plain ole dirac pulse.
That said, I guess it's probably better to keep the term 'coherence' out of subjective audio jargon,
and keep it with transfer functions where it has some real meaning......
...as in the statistical correlation between what's measured vs the stimulus signal.
That’s why we like a linear response plot eh? Loudspeakers behave linear (within boundaries). When the acoustic sum of two drivers in some point of space is linear level wise, the phase behavior is pretty linear too. At least with the systems I have measured. And that complies with the theory.The first loudspeaker is coherent, the second is not.
dave
There can be a gradual phase shift over the audible frequency band while retaining a reasonably flat response. Question is, are we able to detect that. I know not of any research confirming such opinions. On the contrary, the double blind tests I read of prove our ears are quite insensitive to phase shifts that would lead to a non-coherent system.