Spl

[Accord Man]

Originally posted by Prophcy0
The reason the sound was killed is because the sound waves simply canceled each other out. Since they were the same brand/size subs, they were probably emmiting a near exact sound wave. If two soundwaves with the same frequencies/wavelengths hit each other head on (each moving in an opposite direction from the other), they will cancel each other out. If both waves were moving in the same direction and interesected, then the sound would be amplified.

(sorry for the long explanation, we just learned this in my highschool physics class, so it's fresh on my mind)

After reading your post I just about fell off my chair.. But hey, this is a discussion board.. So its cool.. Lets talk a little about bass.

Sound cancellation isn’t as simple/obvious as you seem to think.. Especially when talking about bass.

High school phys has taught you right.. But that theory only applies to directional waveforms (waveforms that are directional) Is bass directional?

How would you go about canceling a bass wave? Invert the sine. And how do we do that? Reverse the phasing of the sub or reflecting the wave. I wont comment on phasing since that’s pretty obvious.. Reflecting waves are a commonly overlooked source of bass loss (in a 2+ sub setup).

i.e. : 2 subs are firing towards the trunk, both wave patterns are almost perfectly parallel. When the waveform is reflected off the trunk, the parallelism is often lost.. Then guess what happens..?




Now that that’s settled, a quick note on the direction to face the subs.. In general, for optimal performance, for a ported setup = facing front, for a sealed setup = facing rear. The trunk lid does NOT act as a sounding board. It simply reflects the bass wave. And the less it vibrates, the better it is (otherwise you are simply loosing bass).




For those giving advice, please only do so if you know what you're talking about.. No good can come when the blind lead the blind.