Does the shape of a sealed enclosure matter?

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Hey folks
Well as autumn draws in I am looking forward to taking my loudspeakers to the next stage, which essentially will involve adding a couple of subs to cover the 20Hz - 100Hz range. The current 'bass' section only goes down to 60Hz or so, and is based on on a pair of old EV SP12Bs in 60 litre sealed enclosures (inspired by the Klipsch Heresies). I like sealed enclosures as they sound cleaner and better controlled, at least to my ears and in my (small-ish and square-ish) room. I am planning on having the subs loaded in sealed enclosures also, which will be decoupled from the upper bass cabs. So after the lengthy preamble, on to my question... as I will stay with sealed enclosures, how critical is it that I go for traditional 'boxes'? Can I go with curvy shapes so long as I respect the internal volumes?

I hope some of you seasoned DIYers can help steer me in the right directions!

Thanks in advance

Inamelotone

PS. I already have a pair of old Philips LF drivers I am planning to use for the subs, which I am told will work well in sealed enclosures, but if any of you have some suggestions for efficient woofers, either 12" or 15", that would do well in this application I am all ears! 😉
 
At what stage of the frequency range does the shape of the interior of the cabinet become something to consider?

I have seen all sorts of curves and bumps incorporated into designs to reduce parallel faces, and break up something or other.

I am about to start a three way design, and am wondering how much attention I need to pay to the design of the bass cabinet (900hz and below).
 
I would not worry too much about the shape, but at 900 Hz, that is high enough to pay attention to edge radius and placement on the baffle. You will probably get many other views. We all have our favorite subjects. In building my last Seas based pair, I found edge diffraction to be far more important than I had ever thought.

900 seems pretty high for a real woofer.
 
Could I just chip in with a related question? In a big sealed subwoofer, does it matter where on the baffle the driver is mounted i.e. symmetrically in the centre, offset towards the top, or offset into a top corner? I'm considering the last of these for maximum flexibility vis a vis allowing me to lay the unit on its side or vertically, for two different possible heights at which to stand the mid/treble box on top...

thanks!
 
In a big sealed subwoofer, does it matter where on the baffle the driver is mounted ...
See it this way: The baffle width and the position of the driver on the baffle are meaningless as long as the baffle width is smaller than the quarter wavelength of the highest frequency in the passband of the sub. Sounds complicated? Then take the upper frequency limit of a sub as 100 Hz. That's a wavelength of 3.4 m. One quarter of that is 0.85 m. If your subwoofer baffle is not wider than that, you can place the driver wherever you want.
But don't overdo it. If you squeeze the driver too tight into a corner, the air trapped in that corner might load the cone there more than elsewhere. This could twist the cone and make the voicecoil rub somewhere.
 
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