Noob Question on ssd15

[alexx01 0]

What does the flatwind coil and bp power options do when buying the subwoofer? Im new to Fi and what the subs for spl.

[john denver 1]

https://ssl.perfora.net/www.ficaraudio.com/sess/utn;jsessionid=154d226b83b34fd/shopdata/0070_Tech/0070_Speakers/0040_Tech.SSD/product_overview.shopscript

[alexx01 0]

https://ssl.perfora.net/www.ficaraudio.com/sess/utn;jsessionid=154d226b83b34fd/shopdata/0070_Tech/0070_Speakers/0040_Tech.SSD/product_overview.shopscript

thanks!