In the custum section i saw you can actually choose between 2 woofer built

1- Standard heavy duty stamped steel woofer basket
or
2- Die-Cast woofer basket.

Actually for 1 6.5 inch woofer there is a 20bucks extra for the Die-Cast. My knowledge are limited unfortunately so i would like to know is the difference between the 2.

Thanks in advance.

Nad C356 DAC & C515
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