Hello again. I have now read the standard ANSI-CTA-2010-B-R-2020 and I understand where my confusion is.If the subwoofer driver only need to cover to 63 Hz, per ANSI/CTA-2010-B, it is acceptable to have a maximum HD2 of -15 dB.
If it has to cover to 160 Hz, the threshold tightens to -24 dB. That means, if the driver has to reproduce both frequencies bands, the "bottleneck" is the 80-160 Hz octave HD+noise limit of -24 dB. It cannot run the <63 Hz frequencies to levels that produces -15 dB of HD2, since if it does that it will cause the >80 Hz frequencies to distort beyond the acceptable limit of -24 dB.
View attachment 299854
The chart above is the threshold of hearing the superius noise generated when the subwoofer is generating tones. You measure the subwoofer and then compare to the values on the chart above.
We have not yet measured the Salon 2, nor the subwoofer intend to replace it.
We do not know if the noise Salon2 generates is above the thresholds! We have not measured the subwoofer that is used by the member who recently purchased a pair of Salon2 either. How can we know that at 20Hz, it generates more noise than Salon2 does?