[Matt Ion]

MOSFET wrote:
Nothing to do with the voice coil shape - it's the surround where you run

into

problems, specifically, in the corners. The further the sub moves, the

more the

corner suspension/surround will have to stretch LINEARLY to accomodate.


That's interesting, but I'm a bit unclear what you mean. Why would the
corner of a square sub have more difficulty stretching linearly than any
other part of the surround? I'm trying to imagine why this is the case, but
I'm not seeing it in my head. I guess part of the reason is that, of
course, I've seen the L7 and know that it has elbow like joints in the
surround corners that provide excellent extension.

Does the issue revolve around the cone twisting (a bit) due to the
flexibility of those corners (while a round cone would remain perfectly
linear)?

Consider that the distance from the cone edge to the basket edge - the area
filled by the surround, which of course forms part of the suspension - remains
the same all the way around a round cone, as it does along the straight edges of
a square "cone" (a misnomer in itself, but that's not important right now). In
the same travel, the distance from the corner of a square cone to the corner of
the surround will increase by a larger amount - simple geometry.

Rounded corners would reduce the effect, but it's still there - as your put a
larger radius on the corners, you'd find the effect reducing until you ended up
with a round cone again.

I haven't seen the "elbow" corners on an L7, but again, they'd have to react
differently than the rest of the surround to accomodate the difference in
extension... and again, you get anomalies in the sound.