high pass filter.

I designed an enclosure for a subwoofer thats tuned to 80hz.  The F3 point is 78hz. If I want a to filter the lower frequencies while still maintaining the most volume possible at 80hz, where should my crossover point be, and should I use first, second, or third order to keep the subwoofer from unloading?  I'm a bit confused about the proper way to handle this issue.

Thanks in advance!

lol....you should be a detective.

It's a JBL woofer model 2202H, and it's actually for installed pro audio, not car audio.  It's tuned at 80hz because I have a Vega Portable Earthquake that'll be providing frequencies from 20-80hz.  While I seem to be doing ok for low end, my mid-bass is less than acceptable, and I hoped that designing a new cabinet for my multiple jbl woofers tuned a lil higher would yield that extra punch that I'm looking for.

Thanks for the input DYohn!

My boss is tight.  I've been telling him for years that these speakers are inadequate, but he insists that they sounded good at one time, and so they must be able to sound good again.  What he doesn't realize is that music program has probably changed quite a bit in the past 20 years that these have been in service at our establishment (plus they were prolly ten years old at that point).  The problem is, we've got six of these woofers, four of which are already in service.

That being said, those JBL's with the horns that I've got them paired with sound pretty good at painful volume levels for vocals/highs, but it seems like they're pretty void of low/mid bass.  I mean, there basiclly isn't any.  I've got one Vega earthquake that provides pretty much all of the low/mid bass right now and it still seems very inadequate.

Thats actually how its setup right now, and it does help, but in this setup I feel like I'm trading off a decent amount of sub bass to gain very little mid bass.  Thats why I decided to try and build this cabinet tuned to 80hz so that I can lower the lowpass frequency of the sub to gain output in both the sub/mid bass ranges.

Would you say that the JBL 2225H's are equally inefficient?  I have a couple of those that I considered using for added bass, but I haven't modeled them at all and really don't know what they're capable of.

https://www.8thstreet.com/product.asp?ProductCode=30261&Category=Speakers   Is this the particular model eminence speaker you were referring to?  There seem to be several different ones labeled Eminence Kappa 12" speakers.  Also, how low would you tune these?  The fs for the speaker in the url is 37hz and I've read that tuning too close to the fs will cause resonant peaks in the mid-range.  Sorry for my lack of experience/knowledge on the subject.

Thanks again for all of your help too!

99db, huh really?  Well I could definately have that wrong.  I'll have to look it up.  I do remember that those woofers roll off significantly at 100Hz though.  The Kappa Pro 12A is a decent woofer for use between about 60Hz and 1.2KHz.  https://www.usspeaker.com/KappaPro-12-1.htm

"Tuning" at Fs will not cause resonance peaks in the midrange.  What causes that in many pro audio loudspeakers is trying to get a large diaphragm (a 12" cone) to behave at higher frequencies.  I did a quick Google on JBL 2225 and it looks like another 25-year-old driver suited for horn loading or bass reflex alignment.  Port it at 40Hz, but beware that it like all the other 2200 series woofers really should be re coned or at least have their surrounds replaced by now if you plan to use them very long.

One final question relative to this crossover.  If I design the crossover to filter an 8-0hm speaker load, and then subsequently wire that speaker system to another 8-ohm speaker system giving a load of 4-ohms, is my crossover still accurate?

I don't understand if the crossover is affected my total resistance or only by the resistance after the crossover?  Sorry for the dumb question!

and thanks again for your assistance DYohn!  Much appreciated!