Automated loudspeaker position switching improves listening-test reliability

Evidence

Making the randomized positional changes caused interruptions in the process, and listeners would lose some of their concentration and adaptation during the intervals. A positional substitution apparatus, in which the active loudspeaker is automatically moved to the same position, is an enormous advantage, saving time and reducing variability in results. This was done at Harman (Olive et al., 1998) and at Samsung, McMullin et al. (2015). There is an ambitious hobbyist version described in an audio forum, MatthewS (2023), so corporate funding is no longer a requirement. Anyone performing frequent subjective evaluations is well advised to make such an investment. Reviewers take note. — Toole, Floyd E, Sound reproduction- the acoustics and…, 555

The positional substitution process was automated using computer controlled pneumatic rams to move the entire platform left and right, and to move the desired loudspeaker(s) to a predetermined forward location, storing the silent loudspeakers at the rear. — Toole, Floyd E, Sound reproduction- the acoustics and…, 1107

Categorization

• SEED: A possible angle: why amateur audio reviewers should adopt controlled positional-substitution rigs rather than relying on memory-based A/B/C comparisons.
• corroborated: 3 independent passages support this claim — Toole, Floyd E, Sound reproduction- the acoustics and…, 555; Toole, Floyd E, Sound reproduction- the acoustics and…, 1107
• XREF: connects to: Loop-switched comparisons give more revealing loudspeaker evaluations than real-time switching; Room differences dominate loudspeaker differences when listeners cannot adapt — Toole, Floyd E, Sound reproduction- the acoustics and…, 547; Binaural headphone tests can replicate real-time loudspeaker listening (+4 more)

Broader Connections

• Virtual headphone testing cut switching time tenfold and improved rating consistency. #corroborates (0.90)
• Loop-switched comparisons give more revealing loudspeaker evaluations than real-time switching #expands (0.85)
• Binaural headphone tests can replicate real-time loudspeaker listening #expands (0.80)
• Listeners habituate to reproduced-sound faults without comparison listening #qualifies (0.80) — , Toole, Floyd E - Sound reproduction-…, 158
• Room acoustics contaminate loudspeaker listening tests needing controlled environments #complicates (0.80)
• Room differences dominate loudspeaker differences when listeners cannot adapt #complicates (0.75) — Toole, Floyd E, Sound reproduction- the acoustics and…, 547
• Listeners can perceptually separate loudspeaker timbre from room coloration in comparisons #expands (0.75)