Highly regarded loudspeakers measured far from flat in anechoic response

Evidence

Starting with my earliest listening tests in the late 1960s, through a prolific research period in the 1980s (see Figure 5.2), up to the present (see Chapter 12), it has been a monotonous truth that in double-blind listening tests, the highest rated loudspeakers had the flattest, smoothest on-axis and listening-window frequency responses. Listeners liked neutral, uncolored, direct sound. Beyond that, loudspeakers that exhibited similarly good behavior off-axis achieved even higher scores—reflected sounds would then have similar timbral signatures. These findings have remained valid in many different rooms over the years. — , Toole, Floyd E - Sound reproduction-…, 1292 (#complicates, via linked claim)

One more important acoustic property of a loudspeaker is its directivity pattern. In an anechoic room, we are only interested in the direct radiation to the listener, but in normal spaces with wall reflections and reverberation the listener receives all these delayed signal counterparts as well. In a relatively reverberant room, it is desirable to use a loudspeaker that has some directivity; that is, it radiates more sound along the main axis than in other directions, especially at middle to high frequencies. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 474 (#complicates, via linked claim)

Categorization

• XREF: connects to: Real loudspeakers show flat magnitude response only below 800 Hz with a midrange dip — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 505; Trained listeners perceive flat spectra from loudspeakers whose on-axis response is flat; Single-axis measurements misrepresent multidirectional loudspeakers like Bose — Toole, Floyd E, Sound reproduction- the acoustics and…, 1946 (+4 more)

Broader Connections

• Anechoic on-axis and sound power responses suffice to predict perceived loudspeaker quality #complicates (0.90) — , Toole, Floyd E - Sound reproduction-…, 1292
• Reverberant rooms make loudspeaker directivity important for sound quality #complicates (0.80) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 474