Quote: |
Originally Posted by danyman no one on this forum are pros at ported boxes to give a guy some help????
anything would be great |
Some comments:
1. I'm able to hit 139dB with two Shiva 12" subs, each in 1 cu.ft. sealed, and driven by 250W RMS. If 130dB is your goal, you should be able to easily exceed that with those subs in vented enclosures.
2. The Qts for that sub is a bit high IMO for a vented box, but if that's what you want to do with it...
4. The manufacturer recommends 2 cu.ft. NET per sub. Your box will have to be a bit bigger than this, to compensate for the space taken up by the sub and the vents.
5. One 4" flared vent should work fine, once you're not shooting for that extra dB or so for a high-SPL setup.
6. Massive Audio's recommendations for port length don't appear to be right. To tune a 2 cu.ft. box to 28 Hz with a 4" port, the port will have to be a bit over 18" long. If the port is 9" long, Fb will work out to around 38 Hz. I suggest going with a longer port - you'll get a smoother bass response, better power handling at lower frequencies and you should still be able to hit that 130dB SPL target.