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Plugging ported speakers and active Xovers

I have recently gotten a JL Audio CR 1 2 way active sub crossover and am wondering about some set up questions regarding the ports in my main speakers (Bryston Mini T's).

I did a lot of reading and was advised by JL to plug the ports in my speakers for better phase/time alignment between sats and subs and enjoyed the resulting tightening/impact/articulation.

My dealer advised that it may not be neccessary as when utilizing a high enough crossover - currently crossed over to stereo subs at 95hz (LR 24db slope) - the port is a non issue as the speaker wouldn't be producing any (real) output at its port tuned frequency, and ported drivers are not sealed drivers i.e. they usually have differently designed motors and a ported driver could be harmed by plugged/sealed operation.

I like the sound I'm getting (love it) but want to be sure I am not damaging the drivers. I am going to try without plugs to see the difference but was hoping for some input. I am also reaching out to the manufacturer. Any input is welcome!!
mhelming
peter_s
1,088 posts
 
Thank you for posting. I am curious about your experience. I have 2JL audio F113 subs, and I'm wondering if the next step might be to procure their active crossover. they certainly speak very highly of it! It seems they have put a lot of thought and design into it. I read one review that suggested that reduction in transparency to the main speakers is extremely minor. What would you say? Did you notice any at all? What have been the improvements that you have experienced by inserting an active crossover in your system? Can you tell us a little bit about your system? What are your main speakers and your main amplifiers? What JL audio subs do you have? Thanks, Peter
rodman99999
3,557 posts
 
Your dealer is correct. Very little output, at the port's resonant freq, if you're crossed over at 95Hz/4th order. If you block the port; you may be robbing yourself of some driver speed and efficiency.
timlub
1,649 posts
 
Trying it won't hurt a thing, but it is way beyond where the port tuning is... an average port tuning is at approximately 30hz, with that port, your woofer is augmented to deliver accurate bass at a much lower frequency than in a sealed box... when you seal that box, all kinds of things change, the woofer is now in a box that is too big for its optimal bass response for a sealed box, the frequency will roll at a MUCH higher frequency vs having it in its optimal sealed box or in the ported box that it is in... The woofer could indeed roll at 80 or a 100 hz naturally with the port stuffed.
If in a very rare case that a woofer is ported in a box that is optimally too small for a sealed woofer, when sealing that box, you will increase that mid bass punch, but only in that case... Again, it won't hurt a thing to try it.
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