Converting stereo to binaural sound requires modeling cross-coupling between speakers

Evidence

To convert normal stereo signals into signals suitable for binaural presentation, it is necessary to filter the left and right channels with the HRTFs associated with the positions of left and right speakers, as shown in Figure 7.15. Note that four filters are involved, because one must model not only the transfer function to each ear but also the cross-coupling of the loudspeakers between the two ears. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 2252

Categorization

• DEFINE: Clarifies HRTF’s role: head-related transfer functions encode how speaker position filters sound reaching each ear.
• SEED: An essay on why headphone ‘3D audio’ marketing oversells a four-filter crosstalk problem could use this as the technical core.
• corroborated: 3 independent passages support this claim — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 2252
• XREF: connects to: Binaural headphone tests can replicate real-time loudspeaker listening; Near-field listening exposes all of stereo’s array crosstalk colorations.; Crosstalk cancellation delivers binaural separation through loudspeakers — Toole, Floyd E, Sound reproduction- the acoustics and…, 304 (+3 more)