Noob question on surrounds

[Torel]

Hello.Material aside, what would happen if i replace a stiff surround on a 12” midbass driver with a softer one? Current Fs is 60hz, qts 0.51. The speaker works in a vented enclosure. Will the qts rise? Will the bass become muddy? Overall, will there be any unwanted effects in sub 800hz range?

[billfitzmaurice]

You'll change everything from Mms to Vas and all of the Q specs. Rather than mess around just get a driver with specs that work for the intended application.

[fpitas]

What Bill said. Plus, if that's an older driver, the stiff surround helped protect the cone from over-excursion. You may end up beating the voice coil to death if you're not careful.

[Chris Roemer]

If your surround isn't damaged, it'd be a LOT easier to retune the box if you want to change the model.