Subwoofer placement severely impacts the electrical power needed for equal low-bass output.

Evidence

Focusing on system efficiency, Figure 14.26(c) shows the average room curve for configuration (b). If one wanted to roughly match the sound output from both configurations, the gain of the four-mid-wall arrangement would need to be turned up by about 9.4 dB, the difference between the MOL values of (b) and (c): −17 dB and −7.6 dB. This corresponds to a power difference of 8.7× for the 20–40 Hz frequency range over which the MOL is calculated. In practical terms, if the subwoofers used in (c) used a total of 100 watts to generate an entertaining level of low bass, condition (b) would require 870 watts. The MSV is marginally better in (b), but not enough to justify the additional power demand. — Toole, Floyd E, Sound reproduction- the acoustics and…, 1618

Categorization

• XREF: Connects to the 8.7x power penalty figure and MOL concept, relevant to understanding how room acoustics imposes real energy costs beyond perceptual ones.