May be so, but again, I linked that article only because it happens to contain the frequency contents of music of different genre, that should allow us to see what sort of load we can reasonably expect the subwoofer to take from the main speakers with high pass crossover set to 80 Hz and above.\nI don't appear to be reading the charts the way you are. My understanding is that the value on the chart is the deviation from average. So, if the line is "40db", then the peak is Average+40db. Nowhere do I see what the average is. I therefore don't know if the peak is 40db absolute, or 140db.\n\nNo the area I refer to is below 200 Hz. The article does not specify the exact range other than stating the frequency axis scale is in kHz. If you look at the graphs, you can see Fig.1 shows 0 to 10 kHz, it looks like log scale, and the you can clearly see it shows contents well below 200 Hz.\nYes. I can see that. And in every case (except perhaps Pop2),the line is already on a downward slope as it passed "0.2" (200 Hz)\n\nIt actually did mention say something above the range below 200 Hz:\n\n"Speech is only locally surpassed by chamber music in the lowest two frequency bands ([110 Hz to 140 Hz]; [140 Hz to 177 Hz]) and by orchestra and opera in the lowest band."\n\n"lowest band" has to refer to below 110 Hz, I would assume, reasonably.\nI don't agree with that assumption. I would read lowest band as "110Hz to 140Hz" as that's the lower of the "lowest two frequency bands".\n\nRegardless: can we agree that there's nothing we would describe as a "massive increase in SPL" occurring below 80Hz in any of those graphs?