Viridian hit it on the head. Moncrieff's research shows that bass becomes non-directional or "loads evenly" at appr 100 Hz. What allows us to precisely place the woofer or subwoofer at frequencies below that are either high levels of harmonic overtones or plain old distortion. This is one of the reasons why downloaded subs sound very different from front loaded subs. The harmonic overtones and distortion are masked to a great degree when downloading, making them harder to localize AND affecting their tonal balance or "attack" characteristics. Try listening to a sub that is downfiring and then turn it on the side so that the driver is now front firing. Other than the difference in the type of footers used, i think that you'll hear a MAJOR difference. Sean
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