Help choosing a Fi sub and box ideas for it...

[bkolfo4]

It is not there at all frequencies.

It is there even when the sub is out of the box.

At the peak "rise" (Fs), the output is not at a low.  Hint: The output doesn't follow this "rise" everyone worries about.

Making decisions based on "rise" is not the best idea unless you are building a burping one note wonder.

When you actually understand that "rise" doesn't matter, let me know.

 

and a little extra - being able to take a sub to the limits doesn't always make it the best choice.  While the peak output may in fact be higher for sub A, sub B might be way louder at lower frequencies making it a better choice a particular application.

[WalledSonic]

14 hours ago, bkolfo4 said:

When will people ever get off impedance rise??? Crap.

The day impedance rise is non existent, soooooo never. 

EDIT: i think the takeaway here is that you shouldnt expect to push a 2000Wrms sub with a 2000W amp. Youre better off oversizing the amp and running it with low gain to avoid clipping and to ensure youre putting enough power to the sub

[bkolfo4]

What happens when you play a frequency where the impedance is not high?

You do understand that a sub is not just "1 ohm" and becomes 3 ohms when put in a box?  I am not trying to be a smart ass, but many people have no clue that this is not what is happening.  

There are frequencies where the impedance can approach DCR.  That being said, with subs it will more than likely be above the crossover frequency, but it will really depend on the driver, enclosure, and the XO frequency the user uses.

Impedance is also at a minimum at port tuning, coupled with excursion being at a minimum.  More power, less cooling. . .

But once again, everyone still misses the fact that the output plot does NOT follow the impedance plot.  It is really irrelevant for a daily musical system.

And a driver that can handle 4000 watts can still perform awesome with only 2k watts.  I have a guy here that was running a UFO BTL and swapped for a SP4.  With only 2500 watts, the SP4 killed the UFO below 35 Hz.