They are the SAME as any subwoofer, but usually the avg joe who thinks he can build subs who thinks multiple stiff spiders etc is going to kick ass will build you a POS. Usually what alot of builders do is build similar to marketed ones and use parts from them or experiment.
They can be better or much worse.
For an 8 the best thing that needs to be implemented is trying to get a deep basket for decent excursion. These subs will usually have a low qts and perhaps highish fs because the cones are light, but there are companies that use looser suspensions and or heavier cones.
you can expiriment with diff cone masses/spider comliances. etc...Take notes and tsps..
The motor is wider then the mounting level lol. You could mount it upsidedown or build it around the mounting baffle which would be cool for novelty and you could have plexiglass to show the motor, I always though of this.
The motors are very strong for a small cone, and it will have sooo much controll it would be better at higher frequencies. You could do something though like a heavy cone if you spray alot of stuff on it or something.
It would also be COOL to see a basket made straight so that the spider landing is about 8 or so.
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