Don't be overly pedantic. As inaudible to human hearing is exactly what the author meant, 0dB (implicitly relative to anything reasonable) actually matches the

Don't be overly pedantic. As inaudible to human hearing is exactly what the author meant, 0dB (implicitly relative to anything reasonable) actually matches the intent better. Also 0dB (relative to no matter what) is closer to the machines actual noise output than -infty dB (think high frequency hum emitted by the PSU and similar).