Originally Posted by maxcichon
Don,
When I did this, I was using an audio test CD and it sounded like the doors were quiet under ~ 180 hZ with 270 uF caps.
Here is another quote from a knowing person (post #25):
"Increasing the capacitance value will lower the cutoff frequency for a highpass filter and allow more bass through.
The formula for calculating the cutoff frequency is...
Fco = 1/(6.283 x R x C)
So for 220 uF capacitor and a 4 ohm speaker (I am guessing about the speaker)...
Fco = 1/(6.283 x 4 x .00022) = 181 Hz.
For a 270uF capacitor, Fco = 147 Hz."
Here's a link...
http://www.qrp.pops.net/filter1.htm
It sounded like 180 hZ . This may say something about the resistance of the speaker/sub in the xFire. Maybe 3.6 ohms under load?
After looking at the crutchfield Bass Blockers, 150's would be your best choice!
Best to you!
Max
Max,
Again thanks for taking the time to research my question, from a laymans point of view using Crutchfields description and my knowledge of home stereo system Equalizer usage (many years) I thought the 150's would be the ticket.....
But I wanted someone who understands the science of the #'s, to verify my guess or point out my error.
That is why I like this forum so much there are very knowledgeable people from all walks of life, who don't mind sharing their expertise!
Thanks again.
When I install them I will report back to the group.
Don