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I'm sick in bed ...
Nothing sinister, I hope, Ben. Best wishes and get well soon.
I'm sick in bed ...
There was an investigation already, cited by somebody else, peer reviewd, to some degree by Toole. What are You aiming for?
Looks completey OK to me. Phase display for the 3kHz looks a bit distorted by the underlying sub-sample shift you have used but of course group delay shape is full spot on, the small base offset of -15us is irrelevant (as it is constant). For ABXing this in foobar, a dummy kernel would be required with the same length and the dirac at the same position to avoid clues from time offsets and/or convolution artifacts etc. Also, crossfade shouldn't be used during ABX, for the same reason (crossfade is considered illegal for official ABX anyway, but I find the hard switching distracting, a fade-out + fade-in would be much better).It would be great to have another contributor check these for correctness.
Looks completey OK to me. Phase display for the 3kHz looks a bit distorted by the underlying sub-sample shift you have used but of course group delay shape is full spot on, the small base offset of -15us is irrelevant (as it is constant). For ABXing this in foobar, a dummy kernel would be required with the same length and the dirac at the same position to avoid clues from time offsets and/or convolution artifacts etc. Also, crossfade shouldn't be used during ABX, for the same reason (crossfade is considered illegal for official ABX anyway, but I find the hard switching distracting, a fade-out + fade-in would be much better).
Most convolvers will take 32-bit floating point data, btw.
IME the 100Hz should be audible for most people with some specific music material, both as a slight timbre shift of steady-state bass notes (when having strong 2nd harmonic) as well as the slight time lag of the "body" of kick drums and plucked upright bass notes. With linear-phase speakers the differences are more pronounced and of course strong room modes can be a show stopper.
Headphones also would apply but for reasons I don't fully understand atm I find phase issues harder to detect with headphones than with speakers.
As mentioned, for proper ABXing with foobar's ABX pluging. Convolver on vs off makes a timing difference that would have to be adjusted manually otherwise (render to wav's and trim them manually with a high risk of getting it wrong unless you put in a marker pulse). And IME it is prudent to change only one single variable in a compare, which is the kernel in this case, and leave everthing else as is. We're not seeking for false positives here.Let me know if you disagree.
I'm hardly going to shut down the discussion or ban all talk of it as you so bizarrely suggest .
Now there's people here discussing time alignment, not for the first time and likely not the last.
This is unavoidable as the system roll-off isn't minphase anymore and must contain "pre-ringing". It is not a true ringing and doesn't sound like one either, rather the time-inversed sort-of exponential decay (hence, attack) sounds more like a noise signal increasing in volume, which is seldom annoying with typical music signals although with step exitation (or 0.5Hz squares etc) it can be heard.
It appears that the literature isn't entirely convincing to a lot of people. ... might make an important difference to THEM … claiming phase distortion is basically the reason speakers don't sound like live instruments (or at least a big part of that).
My aim is ...
^ Filter specs?
Here ..,Where in my posts did I suggest such thing?
Here ..,
" No problem, I'll see my self out, as it seems on this forum moderating doesn't seem to imply cutting off the futile discussions that happened many times before, but in the name of "democracy", it is about letting as many new users to repeat the same bullshit all over again. "
Forums are full of individuals at different stages of learning and levels of understanding, things will get repeated .
If you don't like it , don't participate . Certainly don't start insulting me with accusations of profiteering and incompetence. That will lead you to the exit door, you have had your one free pass .
Please read this ..,So, you were insulted by my opinion that moderating a forum isn't the same thing as policing a forum? IMO it is moderator task to warn users to use search button instead of asking for same quotes and links to the articles that have been quoted/linked for at least dozen of times, but ok, it is up to you to choose how to do your job here.
As mentioned, for proper ABXing with foobar's ABX pluging. Convolver on vs off makes a timing difference that would have to be adjusted manually otherwise (render to wav's and trim them manually with a high risk of getting it wrong unless you put in a marker pulse). And IME it is prudent to change only one single variable in a compare, which is the kernel in this case, and leave everthing else as is. We're not seeking for false positives here.
What i did is far from what you propose but never the less.. I use Mathaudio Room EQ it Corrects both amplitude and phase components of frequency response and much more https://mathaudio.com/room-eq.htm . I tested / did measurements with several column loudspeaker ancient brands from more ore less the same depth en hight approx a meter high all bass reflex system from which 2 with a symmetrical load (build in woofer). Brands where Elipson 1303, JK Acoustics Optima 3 an Vandersteen model 1. Further more i i have some listening experience with Quad ESL 63 an IMF TDL speakers.To conduct a proper test of this hypothesis, it would be necessary to build two speakers that are identical in every respect except that in one, phase undergoes rotation from low to high speaker in a manner like the graph above for the KH310, while in the other, there is very little phase rotation, ideally none at all. This would be a very difficult thing to do, and as such, there may never have been a proper test of this question. Perhaps with a single-driver speaker, listened to close up, digitally equalized to achieve a near-flat response, one without any phase rotation intentionally introduced, the other with phase rotation introduced to mimic speakers like the KH310. Is it possible to do something like this with DSP?
I think before anyone considers doing actual ABX testing, they would want to do some exploration about the impact of the all-pass filters on different songs or sounds. There's no point in setting up an ABX test for material that isn't right to highlight the difference. I made a DSP Chain Preset for each of the all-pass filters I posted, and also a preset for "none". After right clicking the toolbox and activating the DSP switcher, I can switch between the filters (and no filter) in realtime while listening to anything I want. Honestly, I think that would be enough for most people to realize how subtle of an issue this is. I didn't notice any annoying time jumps when switching between my filters, nor when selecting "none".
Back in the 1980s, time-aligned loudspeakers became fashionable, such as the KEF105, KEF107, B&W DM6 (pregnant penguin) etc etc. I did a few experiments with a movable tweeter on a loudspeaker that could be moved back and forth by some 20cm/8". The idea was to hear whether there was any audible effect from moving the tweeter from behind the woofer, so late, to in-line, to forward so early.
Sadly, I and my colleagues couldn't hear any difference over that sort of distance, which was already rather more than any time misalignment due to drivers being on the same baffle.
I can imagine that if the drivers were so far apart that the time of arrival was very different, say a few seconds, then clearly there would be a mismatch between low and high frequencies. So, if a few seconds is too long, what about shorter times? Don't know at what point the two sounds will be perceived as co-incident, but certainly, over the few hundred microseconds of lead/lag I experimented with, there was no audible difference.
With my own current B&W 801s, I used the time-alignment facility on my DCX2496 crossover, just because it's there, but can't say again any difference was audible before and after.
Given the likely path differences between drivers on a typical loudspeaker, I don't see it as significant
S.
If your speaker baffle is not sloped like Thiel, Avalon etc... then you can raise the front part a little bit, make them sloped and listen. Simple experiment. If you hear a change in soundstage (messed up since it isn't designed for that) then time alignment might matter. Not really proof, but merits more research...