oppinion on what to do, stick with current sub or change up?

[CleanSierra]

You had your BL being powered properly, which is why you had tons of control over it. You're now getting an SP4 the same power. It will eat up the power you can give it from a single ZX2500. Get a bigger amp if you want to get response back out of it.

Did you put the SP4 in the same enclosure you had for your BL? If so, then that is probably another problem with the current setup.

[ncc74656]

the BL was on a ZX1500.1 which was exact rated power. i upgraded to a ZX2500.1 and was over powering the BL and it got louder with out a noticeable loss in control. the enclosure for the BL was tuned to 45hz, the SP4 is in a new box that is tuned to 35hz. the ZX2500.1 is damn near rated power and by the birth certificate its only 140W under 3K rms.

for a 4th order what is best? put the magnet into the sealed or vented side of the box?

[TheMonolith2001]

I have a 18q tuned to 28hz in 8 cubes. I would say it is very musical and sounds very nice. VERY flat response. (before cabin gain) You are going to be able to play very low very easily though so how the recording is made is going to have a lot to do with how it sounds. Make an EQ setting that cuts down on the REAL low stuff for crappy recordings and you will be fine.

[ncc74656]

i have been thinking of adding an EQ. maybe it is something ill do at some point. i kinda want to try this 4th order thing to start with. want to try and learn how to do it.