Sub replacement sugestions

[BMS]

So long story short i need new subs. looking for subs 12''  FS below 30hz power handling at last 1500 wrms less than 700$ each

so far ive found 

https://ficaraudio.com/product/sp4plus-series-sp412/

http://www.emfcaraudio.com/emf-audio-banhammer-12/

[CstrokerV]

the regular sp4 the Q's neo and ferrite  the 3 hz i doubt will make a difference and the are awesome sounding subs .. not sure why you want fs under 30 when it usually dont matter when you put it in the box

[BMS]

I'm tuned low and i want the resonant frequency low as well its a daily set up. the sundown x has an fs of 36hz too high.

[slowfkncar]

Might want to take the other parameters into consideration, generally as FS drops so does driver Q and we all know how that affects LFE in a vehicle.

 

https://www.google.com/url?sa=t&source=web&rct=j&url=http://www.mh-audio.nl/downloads/read-measuring-tsp.pdf&ved=2ahUKEwj3jt-qkpHfAhUFHXwKHXGgB6Q4ChAWMAZ6BAgDEAE&usg=AOvVaw0pB7Lmv5ZS4CaDl4H-3dHz

[slowfkncar]

https://knowledge.sonicelectronix.com/car-audio-and-video/car-subwoofers/t-s-thiele-small-parameters/

[CstrokerV]

3 hours ago, BMS said:

I'm tuned low and i want the resonant frequency low as well its a daily set up. the sundown x has an fs of 36hz too high.

So what if you are tuned low after you put it in a box a lot changes and you want to figure out the fb of the sub/box...  the subs fs is at free air not in a box there’s a few articles or responses on here explaining stuff about this stuff