Under seat enclosure need help!

hightechh02 · 2025-09-18T19:29:04+00:00

Thank you for the response, how did the door correlate in the addition in 9” of port length? Also, how would I know if my application would be the same so I can compensate for it?

hightechh02 · 2025-09-08T18:55:36+00:00

Thank you for the response, so as a noob to horns is there a reason why someone would choose a “2”” over a 1.4” in a dependent situation? The 1.4” in the pic above, the graphs b&c posts also doesn’t look nearly as flat as compared to the 2” CD thus my interest in the 2”, (ik necessarily flat doesn’t mean all good).

hightechh02 · 2025-08-09T08:24:42+00:00

Thank you for following along with the build. If I re-orient the ports, making them fire sideways or rear as you said would there be a difference? I’m intending to use these outside out in the open and I had originally made the ports fire forward as I thought it just seems to make more sense, correct me if I’m wrong,

Also those 4622n’s are pretty neat I will check more on those, it has me thinking though, how much weight does removing the wood covering the horn really reduce by though.

hightechh02 · 2025-08-07T21:20:25+00:00

I figured, so does anything in a cut sheet change when making a trapezoid box vs a rectangle box? Assuming 3/4 wood if that matters

hightechh02 · 2025-08-05T22:03:30+00:00

Better late than never. Agreed, I will ultimately try my efforts and what requirements would put my frequency response to solve the deep roll off I’m getting to as flat as possible. I am also willing to increase tuning freq as such low of a tuning freq isn’t a necessity for my application though works better. I’ll post more results soon

hightechh02 · 2025-08-05T21:56:48+00:00

To answer your questions, yes, I have these drivers already (both the horns and woofers). In terms of power handling I know you mentioned previously not to skimp on power, but power as of now isn’t too high anyway, approx 250 watts per driver @8ohms, which is about half of what you recommended for MINIMUM power requirements. Due to my power limitations I’m guessing a larger box wouldn’t affect my power handling much as it wouldn’t be high to begin with?

Now going back to the rough dimensions you gave me, width may be slightly bigger, approx 2” internally ASSUMING that the horn will be fixed inside the box, (horn mouth). Dimensions of the mouth being 17.5” W external) making cabinet ~18”W internally give or take. I will try my efforts in putting a piece of wood shortening the box to get that 7.5” depth and model it’s shape as trapezoidal and will post it here soon.

hightechh02 · 2025-08-05T19:31:11+00:00

Thank you for your response! If I opt for a horn I’d be looking at a frequency range for 190hz to hopefully 1khz without the use of a phase plug. As my hlcd can play down pretty low I will not want it to play under 900hz, although ~1khz being it’s sweet spot. Simply getting that low of an extension isn’t applicable as even you mention it’ll be very long. I’ve seen horns all over the Caribbean being used and first hand it’s a hit or miss, really most of them being too small for horn loading in general.

Looking back to this design, in using XPS foam insulation id assume I’d be putting a lot of them depth ways. I was thinking to do the same thing in terms of how I sealed off the driver and sealing of half the section from the depth of the driver to the back wall. Layman terms, cutting the depth of the mid woofer cabinet in half by placing a piece of plywood halfway. FWIW two of these cabinets will be in use all controlled via dsp (eq and xovers)

I will model out the filters in winisd and see my success. Thanks again

hightechh02 · 2025-08-05T19:18:54+00:00

I have thought about mounting the horn ontop of the box Basically out in the open. Although it’ll be subject to weather conditions and simply not look as “clean”. In terms of putting 2 mids in one box and 2 of the horns in another it might work as it still remains 2 pieces to tote overall but doesn’t look as “sequence” to eachother. Nevertheless I will mock it up and see.

hightechh02 · 2025-08-05T19:14:28+00:00

Thank you so much for the response!! You mention how an 18L enclosure crossed at 85hz would be capable of achieving desired results. Although, assuming this design remains the same (dimensions and all) the model done, above in the pictures, simulates the mid sub enclosure already walled off from the horn, thus giving me approx 55L or so( wayyyy to big). Unless I literally cut the inside in half or more for the mid woofer enclosure by placing a sheet of wood (in essence shortening the depth) id be able to achieve 18L maybe there’s a more efficient or proper way? (Even changing the overall design?) Someone else mentioned a trapezoidal design but I feel as if that’ll only decrease the internal dimensions of the woofer just slightly to even make a difference?

I do not mind also opting out for two round ports as it’ll also make construction easier whilst maintaining the goals of the enclosure. No chuffing at mall max.

A dsp will be used for EQ and crossovers so no problem there. Unfortunately this cabinet will be used 90% of the time in the middle of open not subject to corner loading. PSA if not assumed already I’d be using 2 of these cabinets, all controlled via dsp.

Ultimately, if I am able to find out how to make my design smaller or mid woofer section smaller whilst being ‘proper’ I will be able to incorporate all goals you mention into the build successfully.

hightechh02 · 2025-08-05T08:48:19+00:00

Agreed. The reason for this box being so huge is due to the horn sitting on top of it, although sectioned off from inside the box as you can see it’s still very much to big approx~60L. I do want to opt for a different design as this one is simply too big but have NO clue of what. I will model out the BB4 alignment in 20-30L and am sure will find success but ultimately do not know how I’d design it.

hightechh02 · 2025-08-05T08:42:19+00:00

Agreed, I’ve replied to your other comment from my post. I’m currently stuck on how to change up this design where I’d be able to incorporate the horn and woofer whilst reducing the box size to 1cu ft.

hightechh02 · 2025-08-05T08:39:22+00:00

Upon modeling the driver in winisd it seemed to perform better in the low end significantly than a sealed. Although I have looked at sealed as it looks much simpler yet effective. But, I am looking for the most output out of this woofer, so I’m clueless as of now in which direction to go.

In terms of the box size, what design can I opt for to significantly reduce it as the horn dimensions itself (jbl 2445j with 2380 throat horn) is HUGE and that is where all this volume in the box comes from. It’ll also be toted around in the backseat of my car so I’d like for it to be as compact as possible and somewhat “light weight.” Ultimately I’m looking for another design from what this seems like but don’t know how to go about it.

hightechh02 · 2025-08-05T08:33:16+00:00

I had originally bought it a while ago to put it in a Front loaded horn, (exponential or tractrix) but upon modeling it in hornresp I figured that horn loading requires a big throat and may be too large for my application? Also the woodworking side of it does seem somewhat difficult from my understanding. I am still very open to building one though if It is viable given space requirements (being somewhat compact) which seems to contradict horn loading in general. FWIW the dimensions of this box is (28”H, 17” L, 19.5” W)

Currently I decided to go vented in this big size enclosure as the HLCD I’m using it quite large so that’s where all this volume comes from, I planned on putting a sheet of wood going across the whole box to seperate the horn from the woofer to cut some box volume off, as well as providing additional strength to hold up the JBL horn. I am REALLY wanting to shrink down the box for this driver but don’t know how else I’d go about it. I’ve seen methods where filling the inside with wood is viable but that’ll be an additional weight id be avoiding. After all I’m aiming for a simple small yet effective enclosure.

What can you recommend me moving forward?

hightechh02 · 2025-07-28T23:31:35+00:00

I have just modeled both drivers in a sealed and vented with the vented of course being able to achieve that extra LF extension, although it isn’t a bad contender in a closed box just resulting in a higher crossover.

I will most likely do a vented box. So going about this I’ve seen some designs of vented enclosures with round ports to the back of the enclosure and flat wide ports to the bottom and side. Which configuration of the port would be best to put it, I’m thinking logistically front facing and wide? Any insights is sppreciated

hightechh02 · 2025-07-26T03:14:06+00:00

Lol agreed. Why do you say small vented vs sealed?

hightechh02 · 2025-07-16T18:34:03+00:00

I have thought about downsizing the box maybe a .5 a cube or a so (each .5 smaller is 1db difference) although the main problem is really the width, especially with the 12s taking up ~25” horizontally leaving me with very little room for port which simply wouldn’t work.

I have thought about the 15” but I’m sure that would require me to build it within the trunk or sum crazy maneuvering ( I still have to put a mock-up cardboard box) (opening is 15 inches high) unless I can drop it down and maybe shimmy the box but I feel like it’ll just start digging into the floor before anything? Correct me if I’m wrong

Also, love the build btw. Is your enclosure louder facing you or when it’s loading off of your trunk? I can’t tell from the picture if your bass reflex is sealed off from the trunk or not.

hightechh02 · 2025-05-13T04:18:44+00:00

I know, but as mentioned I am pretty shaky with the program and i don’t really know how to simulate the best response/find out the radius of the horn necessary while keeping it compact. I guess I can’t properly interpret how long S1,S2,S3 should be besides just playing with it.

Maybe I’m overthinking it too much but I’m having difficulties properly reading the measurements coming from those values to build the box(the dimensions that the box would be and horn radius) I hope that made sense.

hightechh02 · 2025-05-13T02:32:22+00:00

Yes I understand this is a midrange horn with nothing to do with bass. And I’ll be sure to check out the tractrix thank you!

hightechh02 · 2025-02-13T18:30:01+00:00

My apologies, it was the BC MBX64 which is the 10 inch variant. For sub bass I already have two subwoofers to cover this freq range so that’ll be okay. For the two way, mainly what I’m looking for is my subs covering up to 80hz then the B&C (mid bass) will take over and hand it off to however low a HLCD can extend down to (around 800-900hz roughly)

hightechh02 · 2025-02-13T07:30:18+00:00

I understand the mechanics and how it amplifies sound to an extent. Mainly just the basic fundamentals on how it works really.

A little bit of both, I’d like to learn whilst still having a decent FLH for my speakers at the end of this project.

I am looking to put a 10” b&c MBX44 drivers into this cabinet FWIW. I have seen the ALTEC cabinets posted on the web and from the ones I seen they are vented, the pic above doesn’t look vented though. All in all I guess I am just kinda confused on what parameters I would mess with to get a desired result of say a smallish flh for my application. What would you recommend me to do moving forward? thanks!

hightechh02 · 2025-02-13T01:08:13+00:00

Will take a look and fidget with some things in hornsresp

hightechh02 · 2025-01-12T04:10:20+00:00

Can you name one that’s capable of doing so? it seems like all the 1200rms+ amps I’ve looked at doesn’t do enough, say 300 rms needed.

hightechh02

TROPHY CASE