The Advantages of Floor Coupled Up-Firing Speakers

But ITD for direct sound and for floor reflection are the same, cone of confusion, no difference between them.

Unless head is pivoted sideways, which in my test revealed the speaker in the floor. But then the cue is ITD from the direct sound.

what we do unconsciously all the time

but the ITD is not from the direct sound unless Your head is heavily asymmetrical - it is ITD of the floor reflected sound
 
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what we do unconsciously all the time

but the ITD is not from the direct sound unless Your head is heavily asymmetrical - it is ITD of the floor reflected sound

ps.
I missed one thing - I considered a real sound source in front of the listener and the single loudspeaker in front of You in Your "head tilting" test ...while the speakers in the stereo setup are not in the median plane!

so yes - You are partly right - tilting listener's head can result in both ITD of the direct sound and of the floor reflected sound

however the latter will be much bigger
 
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For source and reflection to be on the "cone of confusion", the distance has to be the same but it is not.

Good point about the distance ! Then it means that only in median plane ITD does not change with height. In stereo triangle floor reflection produce ITD different from ITD of direct sound.

On the other hand, in my test the floor dipole was in the median plane. It still got perceived on the floor by head movements.
 
Is the interaural time difference between the direct sound and the floor or ceiling reflection the same?

We are talking about first order effects here (and these approximations are good enough). Yes, the binaural differences are comparable.

The cone of confusion conceptualizes of the listner's head as a bowling ball with ears symetrically place about the midline (your nose).

Are there perturbations with a "real" head in the sound field? Sure, but for the purpose of engineering consumer audio, those would be relatively minor effects on the ITDs. If you are talking about high frequency HRTFs (and we are not), that, of course, is a different story.
 
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now please consider all this in the time domain instead

There isn't a *reflection*, the wavelength is so long that it's integrated in time.

A reflection requires a change in direction of the wavelength, under Elias's example the wavelength is so large that it hasn't even formed yet to have the opportunity to change direction. Nor can you simply look at a portion of the wavelength with respect to a reflection.

At lower freq.s there is diffraction and the potential for a resonant condition.

(..under Elias's example, assuming the speaker was centered in the room, then at 400 Hz he could have a reflection off of any wall and the ceiling.)
 
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There isn't a *reflection*, the wavelength is so long that it's integrated in time.

A reflection requires a change in direction of the wavelength, under Elias's example the wavelength is so large that it hasn't even formed yet to have the opportunity to change direction. Nor can you simply look at a portion of the wavelength with respect to a reflection.

Can You please post any reference for this?