A 100Hz LPF filters everything above 100Hz, not just ILD or some other factor. Likewise, crossfeed is crossfeeding everything (by a determined amount) below a set threshold, not just ILD but all the sound which includes all the timing, spectral and other information used by our perception.
filters filter one channel without the knowledge of other channels. Since ILD is a property of how channels differ from each other, it doesn't "exist" for the filter. Nor does any other spatial cues that are based on channel differencies such as ITD or ISD.
Stereo sound in L/R form can be transformed into M/S from (Mid/side) where Mid is "centered mono" (left and right channels are the same) and Side is the difference of left and right channel. Since Mid/Side processing is common in music production/mixing, I thought you'd be familiar with these concepts. No wonder my analyse of the binaural recording seemed to go over your head. If you are unfamilar with this you can study it for example here:
https://www.izotope.com/en/learn/what-is-midside-processing.html
We’re dealing with stereo, so a mono signal is a signal which only occurs in either the left or right channel and obviously crossfeed does change that. If you’re talking about the perception of a sound in the phantom centre, then that’s a dual mono signal and summing them together does change it to an extent (it increases at least the level).
You are talking about mono in "mixing" context. Mixers work like that. There are pan laws and what not, but elsewhere mono is a simpler concept. In this (stereo consumer audio) context it is just all the stuff that is the same for left and right channels, the "M" channel. In mixing context we can have a mono track panned hard (100 %) left, but in crossfeed context this is not at all mono sound, because you can't use mono playback system to indicate left channel has sound while right channel is silent. You need stereo playback system for that. It is stereo sound that was created by hard panning mono sound. The whole point of panning mono tracks in mixing is to create stereo from mono!
Furthermore, in most cases even a sound in the phantom centre is likely to have stereo reverb (artificial or acoustic), variations between the left and right channels and therefore the potential for spectral and timing/phase issues.
Yes, you are right.
There are always objective and subjective elements, the trick is understanding which is which and not making false assertions about the former based on the latter. This case is tricky because we’re talking about subjective responses which don’t have precise definitions/descriptions and which vary considerably between different individuals.
Yes, but we can't ignore the fundamental problem of spatiality created for speaker in headphone listening. Back in the day tv series were produced for 4:3 screens. Then came 16:9 TVs and people watched 4:3 shows widened on their 16:9 screen. To keep the original aspect ratio and picture shape, you need to add "black bars" on the left and right. Luckily TV had that property even if many didn't "like" if for the black bars, but crossfeed is a similar thing, just for sound. I want to experience the spatiality at the "scale" it was created for speakers, not in a scale of excessive spatiality.
No you can’t because you are wrong. With speakers the left channel does not “leak” acoustically to the right ear! What actually happens is that the signal from the left speaker reflects off the left and right walls of the listening environment, so now we have a mixture of direct and reflected sound with different timing and spectral content.
The sound of course reflects in many other surfaces too. From floor. From ceiling. From back wall etc. These reflections can ruin speaker spatiality if the room is acoustically bad.
Anyway, NONE of this happens with headphones, BUT if you use crossfeed, you simulate part of it, the part of direct sound from speakers. It is like having the speakers in an anechoic chamber. No reflections! Only direct sound! I am not wrong because I don't make the claim you say is wrong! I am making a claim that is right.
Some of the direct sound and sound reflected off the left wall reaches your right ear but is further affected by your skull and pinnae (attenuated and spectrally altered), the reflections from the right wall do not have to pass through your skull to reach your right ear but are affected by your right pinnae. What we actually get is very significantly different from just crossfeed, so you can’t just keep repeating “Same happens with speakers.”!
That's complete semantic nitpicking!! I have said crossfeed simulates ONLY acoustic crossfeed of direct sound and indeed that DOES happen. Of course the lack of of the reflections AFFECT the sound, but the same happens without crossfeed! Lack of room acoustics is not a crossfeed problem. It is a headphone problem! Crossfeed solves the lack of direct sound acoustic crossfeed problem.
No, the result is not similar it’s very different as explained above and as you already know but are ignoring!
Still less different from not using crossfeed. You think you can only do things if you can do them 100 % perfectly. I think 1 % improvement is an 1 % improvement. That is our fundamental philosophical difference.
But you’re not “fixing only one problem” because you are not only crossfeeding ILD, you’re crossfeeding all the signal below the threshold and by fixing one problem you’re making other factors/considerations worse. 4+4+4=8 if you ignore/dismiss that last “+4”, which I don’t really notice and doesn’t affect my enjoyment anyway!
The pros win the cons easily for me. If it was the other way around, obviously I wouldn't like crossfeed. To me headphone sound as it is is so wrong that sound that is wrong, but less wrong is a huge improvement. Maybe you can explain me what exactly are these bad things (that aren't bad without crossfeed) I do not notice. Again, I have listened to crossfeed thousands of hours. If there is something to notice, it must be something really hard to notice!
But what if it’s not the most harmful one? What if all the other factors combined, which you’re damaging by fixing that one problem, are more harmful? What if you don’t find that problem you fixed to be that harmful a problem to start with?
Such questions could be made about everything in life. I have thinked a lot what crossfeed does to the music and I just don't believe in harmful things. If there is something, it must be very minor. Frankly I think you fear "damage" too much. You don't trust crossfeed. To me listening to music mixed for speakers on headphones is the damage and using crossfeed makes the damage less harmful for enjoyment.
You have a particular perception and you’ve invented an idea/theory that explains it by effectively dismissing/ignoring everything that your perception isn’t consciously aware of and you don’t believe is harmful.
So people should not invent ideas/theories? Again, I am NOT ignoring anything. I have just concluded those things insignificant. You keep touting these ignored things, but you have zero theories how they ruin things in crossfeed. It is like saying mankind can't go to Mars without taking account the mating habits of unicorns, but not explaining how the mating habits of unicorns affect space travel to Mars.
If your perception were the same as everyone else’s then maybe you’d be on to something but clearly it isn’t. If your theory of solving the most “harmful” problem and being closer to ideal were correct, then why, after being around for 50 years or more, don’t we see it as standard or at least as an option on every headphone device, especially as it has the potential to be a money earner? It’s never taken off and science knows why but you dismiss this too and instead falsely assert it’s due training (or previously ignorance or idiocy).
Crossfeed is not a "standard" in every device, but it hasn't gone away either. To my experience crossfeed is insanely difficult to sell to people, because it requires understanding of human spatial hearing which most people don't have and for a novice the benefits of crossfeed can be difficult to figure out. As it kills superstereo, many people think it makes the sound duller, more mono and removes detail. I don't blame those people, because it takes time to learn to appreciate crossfeed. I can't "sell" crossfeed even to you, so how could I sell it to someone who understands nothing about spatiality and audio?
It appears you’ve fallen into the same logical trap so many audiophiles do with other aspects of audio. They have a perception, find or invent explanations that support it and ignore or dismiss anything to the contrary. Typically you do not fall into that trap, unless it includes the letters “ILD”!!
G
I am happy in this trap...