Battling Imp rise?

[Boon]

first, impedance rises in multiples. if you have 2x rise at 40hz then at 2ohm you rise to 4ohm. you wont have a rise of .2ohm above 1ohm. if you can prove that wrong id LOVE to know what you have done lol.

Just checking... have you ever actually looked at an impedance plot? It is possible to have exactly 0 ohms of rise.

You have NIL rise when the cone is stationary. No movement = no inductance = no impedance rise.

If you plot the velocity of the cone, it's 90 degrees behind the phase of the wave being played. In other words, when the amplitude of the wave is at maximum, the velocity is at minimum. Also known as nil. Because when the cone reaches the top of the stroke, the velocity decreases until for a fraction of a second, the cone stops. The lower the frequency, the longer the period during which the cone is moving very, very slowly.

[bassl0va]

Just checking... have you ever actually looked at an impedance plot? It is possible to have exactly 0 ohms of rise.

You have NIL rise when the cone is stationary. No movement = no inductance = no impedance rise.

If you plot the velocity of the cone, it's 90 degrees behind the phase of the wave being played. In other words, when the amplitude of the wave is at maximum, the velocity is at minimum. Also known as nil. Because when the cone reaches the top of the stroke, the velocity decreases until for a fraction of a second, the cone stops. The lower the frequency, the longer the period during which the cone is moving very, very slowly.

Are you saying that the impedance changes at various stages through the cycle when playing a single note?

Like if you play 20hz and the amp is wired at 0.5 ohms (lets say that the box is tuned low enough that the sub doesn't bottom out at full power with no subsonic filter) when the cone is moving it may go up to 2 ohms but when it reaches the peak of the cycle the ohm load drops down to 0.5? Is that what you mean? That would screw up the waveform wouldn't it o_O ?

Edited September 26, 2010 by bassl0va

[Eric B]

haha, ya that is true. but i still disagree that its not important for daily. lets say some one is running a sundown 1500 at 2ohm. the amp should do 800w but with 3x imp rise now it at 6ohm and its only doing 300w. well now you wire the amp to .5ohm, rise to 1.5ohm and you get about 1000w. now you have more than tripled your power for free. so even if you arnt burping, you now know that the amp isnt doing the power you thought and what you might have thought would be over powering would actually be giving correct power.

Nice example but Ive clamped a SAZ-1500 wired at .66 rising to 1.9 and it was doing ~1948Watts lol

[fecupe2001]

What boon said is that impedance rise changes on every frequency, if you have a big rise on a certain frequency it doesn´t mean it´s constant, maybe you can have 0 ohms impedance rise on another one causing danger to you amplifier if it´s wired below 1 ohm and it doesn´t like it