David, you posted something earlier that resonated (no pun) with me. You said...
So how does the brain measure this timing? By the latest research, it appears to have 2 mechanisms, one, that works on higher frequencies, higher than the wavelength of the head’s size, that is based on group delay / correlation, i.e. the brain can match the same signal arriving to both ears and time the difference and another mechanism for lower frequencies, that can detect phase, likely by a simple comparator and timing mechanism. The two overlap.
Phase hmmm. If a point source of sound has a given freq range and originates as all freq at zero phase AND, air is dispersive as is all mediums, more phase change at different freq could be interpreted as farther. Ok. Well I was curious and looked at the phase plots of my speakers. Phase varies fairly smoothly from about -40 deg at 50 hz to about +34 deg at about 500 hz and is flat after that for about 2 more octaves. 30deg is considered alot and over the most "important" freq to humans, this is twice that. Point is, IF phase is used by our brains/ears to judge distance (rather than just delays for orientation), especillay at low freq, with speakers doing that how is "depth" and what we call staging not affected negatively? In my field, as I suspect audio is, phase is usually ignored as it's a nearly intractable problem for the most part. I wonder if sampling/digitization etc and its issues could end up being a red herring as they pertain to this topic of natural (organic) sound.
This doesnt address the source (CD or vinyl) question and their imaging differences but maybe someone can interject the phase aspects of the two to possibly add to the discussion.
So how does the brain measure this timing? By the latest research, it appears to have 2 mechanisms, one, that works on higher frequencies, higher than the wavelength of the head’s size, that is based on group delay / correlation, i.e. the brain can match the same signal arriving to both ears and time the difference and another mechanism for lower frequencies, that can detect phase, likely by a simple comparator and timing mechanism. The two overlap.
Phase hmmm. If a point source of sound has a given freq range and originates as all freq at zero phase AND, air is dispersive as is all mediums, more phase change at different freq could be interpreted as farther. Ok. Well I was curious and looked at the phase plots of my speakers. Phase varies fairly smoothly from about -40 deg at 50 hz to about +34 deg at about 500 hz and is flat after that for about 2 more octaves. 30deg is considered alot and over the most "important" freq to humans, this is twice that. Point is, IF phase is used by our brains/ears to judge distance (rather than just delays for orientation), especillay at low freq, with speakers doing that how is "depth" and what we call staging not affected negatively? In my field, as I suspect audio is, phase is usually ignored as it's a nearly intractable problem for the most part. I wonder if sampling/digitization etc and its issues could end up being a red herring as they pertain to this topic of natural (organic) sound.
This doesnt address the source (CD or vinyl) question and their imaging differences but maybe someone can interject the phase aspects of the two to possibly add to the discussion.