Excessive center-channel upmixing damages music soundstage rendering

Evidence

The problem: too much uncorrelated sound arriving from behind the listener, scrambling the information in the direct sound from the loudspeakers. Lesson: there can be too much of a good thing. The ETC probably looked just fine, though. Somebody measured but did not listen. — , Toole, Floyd E - Sound reproduction-…, 702 (#corroborates, via linked claim)

In Sections 4.4 and 4.5 it was shown that from the point of view of sound quality, the most challenging listening tests for loudspeakers were those done in mono. People heard and complained about resonances in loudspeakers. Adding a single channel for stereo made listeners less responsive to flaws in loudspeakers, as persuasively shown in Section 4.4. Adding more channels in multichannel made them even more forgiving (Figure 5.7(b)). Simple logic suggests that the complexity of the sound field in the room was responsible. The ray diagrams in Figure 5.12 are persuasive evidence of that. But, if the resonances were in all the loudspeakers, why would having more of them playing simultaneously make the resonances less audible? — Toole, Floyd E, Sound reproduction- the acoustics and…, 568 (#corroborates, via linked claim)

Categorization

• XREF: connects to: Center channel carries most dialog but stereo mixing habits undermine TV use; Most commercial Atmos mixes are embellished stereo using little center channel; Excess uncorrelated rear-wall sound can destroy the phantom center image — , Toole, Floyd E - Sound reproduction-…, 702 (+5 more)

Related

• Excessive rear-wall diffusion can destroy the stereo center image (similarity 0.87)
• Center channel carries most dialog but stereo mixing habits undermine TV use (similarity 0.86)
• Excess uncorrelated rear-wall sound can destroy the phantom center image (similarity 0.83)
• Multichannel spatial information masks loudspeaker coloration in playback (similarity 0.83)
• Stereo presentation masks audible differences between loudspeakers found in mono. (similarity 0.83)
• More playback channels increasingly mask audible loudspeaker resonances (similarity 0.83)
• Two-channel stereo only works for one centrally seated listener (similarity 0.82)
• Phantom center image sound quality is inherently compromised even in the sweet spot (similarity 0.82)
• Upmixers that overuse the center channel degrade the stereo music soundstage. (similarity 0.82)
• Home theater center channels are often inferior despite being the most important speaker (similarity 0.81)
• Adding rear channels to stereo does not improve spatial diffusion (similarity 0.81)
• Stereo and multichannel listening make listeners more forgiving of loudspeaker flaws (similarity 0.80)
• Off-center listeners lose the stereo illusion but retain musical content (similarity 0.80)
• Most commercial Atmos music mixes are embellished stereo rather than true multichannel. (similarity 0.79)
• Stereo playback masks differences between loudspeakers with room reflections (similarity 0.79)

Broader Connections

• Excess uncorrelated rear-wall sound can destroy the phantom center image #corroborates (0.90) — , Toole, Floyd E - Sound reproduction-…, 702
• More playback channels increasingly mask audible loudspeaker resonances #corroborates (0.85) — Toole, Floyd E, Sound reproduction- the acoustics and…, 568
• Multichannel spatial information masks loudspeaker coloration in playback #corroborates (0.85)
• Phase shift is largely inaudible for reproduced music in reflective rooms #qualifies (0.75) — Toole, Floyd E, Sound reproduction- the acoustics and…, 972
• Crosstalk cancellation can expand the stereo soundstage from ±30° to ±90° #expands (0.75)
• Off-center listeners lose the stereo illusion but retain musical content #complicates (0.70) — Toole, Floyd E, Sound reproduction- the acoustics and…, 395