Re: Making Subwoofer Cabinets

On Oct 30, 12:18 pm, almfr...@xxxxxxxxxx wrote:
also, those first box specifications i came up with, i created by
taking the measurements of an 18inch Peavey PA subwoofer, and
decreased them by a ratio of 12/18.

Sorry, that won't work.

Even given the most simplifying assumptions, it's wrong.
consider, for example, the moving mass of the cone. All
other things being equal, it's NOT going to go as 12/18,
but it's going to go as the SQUARE of that ratio.

So instead of a ratio of 2/3 (12/18), it's more like a ratio
of less than 1/2 (144/324). And that's just ONE parameter.

Making simplifying assumptions like this is almost
guaranteed to lead you to a bad design.

And i figured that would be a
ballpark estimate if i'm going to be building a high power sub. the
reflex port measurement i generated by using an online calculator that
estimates the port size based on the diameter of the driver and the
maximum reflexion of the driver (which i estimated by measuring the
suspension) at a certain frequency.

It would do you well to use the lingua franca of the domain.
"maximum reflexion of the driver" has no standardized
meaning.

As such, it would appear that you are confusing the
temr "Resonant frequency," and, if so, the method you
suggested you used will NOT lead to any meaningful result.

are these legitimate guesses? or crap?

Crap. Simple as that.

.

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