Re: 15's that sound great and get loud with about 600 rms SEALED
The 600 watt OA 15 has an EBP of 40, which lends it very well to sealed applications. If you're dead set on locking your subs in a sealed box, they would be a good choice.
When you're looking at subs, divide the Fs by the Qes and the result is the driver's efficiency bandwidth product (EBP). Drivers below 50 will do better in sealed or 4th order applications. Drivers between 50 & 100 will do well in either and those above 100 will do better in ported or 6th orders.
Or at least, that's the common wisdom. I've found that drivers above 70 don't like sealed boxes at all and drivers above 100 are few and far between. Fifty to 70 do well in either and below 50... seldom do well in ported. But... that's not a rule, just a guide.
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