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Discussion Starter #21
I'll just search Google and the forum for the answers that I need, you guys have been great, thanks so much!!
 

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I don't think a jigsaw will suffice for cutting a slot port, unless you are REALLY good with it over long distances. If someone can cut the long side or if you can pick up some wood pre-cut like with a saw at Home depot assuming it is accurate enough, this is doable.
 

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Discussion Starter #23
I don't think a jigsaw will suffice for cutting a slot port, unless you are REALLY good with it over long distances. If someone can cut the long side or if you can pick up some wood pre-cut like with a saw at Home depot assuming it is accurate enough, this is doable.
I meant for cutting the hole for the face.. I've picked up a a table saw, circular saw, sawzall, I've also got the router with a few tips.. learned to set up jigs for circles and square cuts..

Correct/square cuts are no longer a concern.. I may actually go so far as to remove all the carpet, hit it with orbital, spray bedliner on the box, route the edges smooth..

I'm just not sure if I'm supposed to be working with/ inputting inner or outer dimensions for port calculation..

If the port has to be a long and shallow, running lengthwise along the bottom of the box, would probably make my life easiest..

.. ..
 

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Ah, looks like you're in the clear with a table saw and so on, then.

So yes, always measure INSIDE, that's all the air "cares" about. Any 90 or 180 degree bends or whatever, use the middle measurement for the number. Example, a 4x8 port, turns 90 degrees... you'd go in that port and visualize the 45 degree angle of each piece of wood it would take to make it, and use the measurement from the inside middle of that. Simpler done than even explained.

edit: Here's a pic to explain better than words


I meant for cutting the hole for the face.. I've picked up a a table saw, circular saw, sawzall, I've also got the router with a few tips.. learned to set up jigs for circles and square cuts..

Correct/square cuts are no longer a concern.. I may actually go so far as to remove all the carpet, hit it with orbital, spray bedliner on the box, route the edges smooth..

I'm just not sure if I'm supposed to be working with/ inputting inner or outer dimensions for port calculation..

If the port has to be a long and shallow, running lengthwise along the bottom of the box, would probably make my life easiest..


.. ..
 

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Discussion Starter #25 (Edited)
Ah, looks like you're in the clear with a table saw and so on, then.

So yes, always measure INSIDE, that's all the air "cares" about. Any 90 or 180 degree bends or whatever, use the middle measurement for the number. Example, a 4x8 port, turns 90 degrees... you'd go in that port and visualize the 45 degree angle of each piece of wood it would take to make it, and use the measurement from the inside middle of that. Simpler done than even explained.

edit: Here's a pic to explain better than words
Appreciate all the trouble, the JPG made it clear..



On port velocity, I'll do some reading, but what are acceptable numbers for these 2-12s within this much airspace? You mentioned 3" as a no go.. I now have the option of 4" (found another hole saw)

You see, I'm working with a seriously limited budget and dare I admit, woodworking skill set.. round ports would be simplest, although I'm up for the learning experience of working the wood for slot port..

Still, I'm limited by the tools available to me, my old table saw dug up from my Uncles house is missing the rip fence (mind you, I purchased it new for a job at his house, used it once, left it there 10 years ago, found it buried under a mountain of shit, two critical pieces missing.. The stand and the rip fence) I have to use a pair of clamps, tape measure, and a long level as straight edge for makeshift rip fence. NIGHTMARE...

I will stop by Lowes or Home Depot, see if I can purchase a rip fence for the saw I have.. otherwise, a few simple cuts will end up taking half the day..

I could get the slot port done, but round would be simplest..

I will download the version of Winisd you recommend, will poke around for a bit then it's off to get some work done..
 

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Just wanted to say, if it hasn't been already, be extremely careful with your table saw and make shift fence. With your self admitted limited wood working experience and a fence that isn't properly secured, that saw becomes extremely dangerous. Just look up table saw kick back and you'll see what I mean. I'm 40, been a carpenter and cabinet builder most of my life and I've had a couple of kick back scenarios even with a good quality fence that was properly secured. Any shift in the work piece while it's being cut can catch the back of the blade and it can be shot back at you. It happens so quickly you have no time to react. If your hands are near the blade they can be pulled in to the blade, seriously not a good thing. I've once had a piece of 1/4" plywood shot back at me and it hit me in my upper thigh, just below of my waist and just shy of my "area". It caused a welt the size of a golf ball and a cut requiring 18 stitches. Just saying, be careful...better yet, get a proper fence or a saw with one. The most killer sub box isn't worth the risk.
 

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Discussion Starter #27
I just skimmed through this thread, apparently I missed the part about passive radiators..

I know what they are, but I would not know how or where to begin with calculations...
 

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I just skimmed through this thread, apparently I missed the part about passive radiators..

I know what they are, but I would not know how or where to begin with calculations...
Again, use of WinISD Pro can provide necessary info.

They aren't cheap but it works great because you don't take up space with ports, AND they are tune-able.


OK so I modeled an approximately 8 cubic foot box with two subs, and two 15" CSS passive radiators. With 500g of added weight on the the radiators, this matches (roughly) a 24hz tuned port.

Comparatively, that tuned port requires Three 4" round ports to avoid heavy chuffing.

In both of these sims, I used a 15hz infrasonic filter to keep excursion from possibly being an issue.


At 500W total power, SPL for either of these options is about 115.5dB anechoic.
 

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Discussion Starter #29
Just wanted to say, if it hasn't been already, be extremely careful with your table saw and make shift fence. With your self admitted limited wood working experience and a fence that isn't properly secured, that saw becomes extremely dangerous. Just look up table saw kick back and you'll see what I mean. I'm 40, been a carpenter and cabinet builder most of my life and I've had a couple of kick back scenarios even with a good quality fence that was properly secured. Any shift in the work piece while it's being cut can catch the back of the blade and it can be shot back at you. It happens so quickly you have no time to react. If your hands are near the blade they can be pulled in to the blade, seriously not a good thing. I've once had a piece of 1/4" plywood shot back at me and it hit me in my upper thigh, just below of my waist and just shy of my "area". It caused a welt the size of a golf ball and a cut requiring 18 stitches. Just saying, be careful...better yet, get a proper fence or a saw with one. The most killer sub box isn't worth the risk.
I missed this too!

I have the actual saw blade cover with the anti-kickback mech secured.. It's just the actual rip fence which is missing.. I am using a a long level as straight edge w clamps to secure for straight cuts.

Thanks for all the info, appreciate the concern!..
 

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Discussion Starter #30
Again, use of WinISD Pro can provide necessary info.

They aren't cheap but it works great because you don't take up space with ports, AND they are tune-able.


OK so I modeled an approximately 8 cubic foot box with two subs, and two 15" CSS passive radiators. With 500g of added weight on the the radiators, this matches (roughly) a 24hz tuned port.

Comparatively, that tuned port requires Three 4" round ports to avoid heavy chuffing.

In both of these sims, I used a 15hz infrasonic filter to keep excursion from possibly being an issue.


At 500W total power, SPL for either of these options is about 115.5dB anechoic.

Since I dug up a brand new 4" holesaw which I forgot I had, I've already purchased the 4" PVC..

I'm having a nightmare of an ordeal fixing broken tools (turns out the router I purchased brand new from Lowes was returned by previous owner with broken handle and broken height adjustment lock release..

Since I decided to make it a Sat night project, I was relegated to trying to rig a router.. Threw in the towel after I mangled the doubled up plywood panels..

Sorry I put you through the hassle of researching passive radiators, I'm not sure why I even posed the question, I was hoping to get the box done tonight..

Anyway, Matt from Parts Express modelled my subs in whatever program they use over there..

Showed a decent plot with only 500 watts, calls for 2 4" ports and 7.5 cf internal..

Plot showed a minimal dip below 0 from 22hz all the way to 50 where it hits the 0 line..

I asked about port velocity, according to his program, the pair of 4" PVC ports won't be a problem..

Not sure if it makes a difference that I'm actually running 500 rms per sub, not sure if he was aware of that when plugging in data..

Anyway, time for a movie :) Thanks again guys, I'll keep you posted!
 

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Matt from PE mis-calculated, unless you are operating under 400W. 34 meters / second is the target at least as far as the most you'd probably tolerate. Bear in mind, that is ~.1 MACH.

With two ports 4", you'd be best off adding a large infrasonic filter @ 25hz. By doing this, you'll be able to keep port chuffing below crazy levels.


Since I dug up a brand new 4" holesaw which I forgot I had, I've already purchased the 4" PVC..

I'm having a nightmare of an ordeal fixing broken tools (turns out the router I purchased brand new from Lowes was returned by previous owner with broken handle and broken height adjustment lock release..

Since I decided to make it a Sat night project, I was relegated to trying to rig a router.. Threw in the towel after I mangled the doubled up plywood panels..

Sorry I put you through the hassle of researching passive radiators, I'm not sure why I even posed the question, I was hoping to get the box done tonight..

Anyway, Matt from Parts Express modelled my subs in whatever program they use over there..

Showed a decent plot with only 500 watts, calls for 2 4" ports and 7.5 cf internal..

Plot showed a minimal dip below 0 from 22hz all the way to 50 where it hits the 0 line..

I asked about port velocity, according to his program, the pair of 4" PVC ports won't be a problem..

Not sure if it makes a difference that I'm actually running 500 rms per sub, not sure if he was aware of that when plugging in data..

Anyway, time for a movie :) Thanks again guys, I'll keep you posted!
 

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Discussion Starter #32
Matt from PE mis-calculated, unless you are operating under 400W. 34 meters / second is the target at least as far as the most you'd probably tolerate. Bear in mind, that is ~.1 MACH.

With two ports 4", you'd be best off adding a large infrasonic filter @ 25hz. By doing this, you'll be able to keep port chuffing below crazy levels.
OK, this is the last I will trouble you with this.. I have figured out how to quickly make straight square cuts for building slot port..

So port velocity will be too high @ 22hz regardless of the quantity of ports? Adding a few ports won't solve the problem will it? I'm assuming it won't, or the port lengths required will equal some absurd type length..

I don't have a box building program, hence all the badgering.. I will check back later today, if 4" down to 22/24hz is an absolute moot point, I'll build a slot port..

Heading downstairs to work on the box.. Will check back later!
 

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It isn't trouble, so please don't think of a conversation of this stuff like that. Nobody is born with an innate ability to figure out audio, we all learn it. My first box was a fucking mess, as was my second, and third, and around the 4th I started getting a grip on it, etc.

Port velocity drops with the addition of ports. However port length will increase per port. Just stay accurate with your calculations, and remember that the ports take up room so you're working with a moving target. The trick is to calculate, think it through, re-calculate, etc before cutting a single board.

When you say you don't have a box building program:

https://www.facebook.com/WinISD/posts/126113234166443

Now you do.

OK, this is the last I will trouble you with this.. I have figured out how to quickly make straight square cuts for building slot port..

So port velocity will be too high @ 22hz regardless of the quantity of ports? Adding a few ports won't solve the problem will it? I'm assuming it won't, or the port lengths required will equal some absurd type length..

I don't have a box building program, hence all the badgering.. I will check back later today, if 4" down to 22/24hz is an absolute moot point, I'll build a slot port..

Heading downstairs to work on the box.. Will check back later!
 

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Discussion Starter #34
It isn't trouble, so please don't think of a conversation of this stuff like that. Nobody is born with an innate ability to figure out audio, we all learn it. My first box was a fucking mess, as was my second, and third, and around the 4th I started getting a grip on it, etc.

Port velocity drops with the addition of ports. However port length will increase per port. Just stay accurate with your calculations, and remember that the ports take up room so you're working with a moving target. The trick is to calculate, think it through, re-calculate, etc before cutting a single board.

When you say you don't have a box building program:

https://www.facebook.com/WinISD/posts/126113234166443

Now you do.
Appreciate all of this! I know I sound like such a noob, been doing this a while although I've always had boxes built to order as per manufacturers recommendation.. (with great results) I can install, I can tune, not great with fab, have always outsourced.. Another thing I want to point out, I was active 5 or 6 years back, fell out of the loop, back in the saddle, much has changed, much remains the same..

SQ/SQL is a recent thing when compared to the length of time I've been tinkering with car audio (late 80s, early 90s) a bit more involved these days

I've learned more with my time on this forum (member since 2008?) than I have in all my life..

It's all info I get from good folks like you.. Appreciate all the info, I'll let you know how it goes!
 

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Discussion Starter #35 (Edited)
Ok, here's what I have.. With 6- 4" ports (easiest for me) I peak out at 55.155 m/s @ 23.79 hz..

From 22.07hz I have 34.366 m/s, sharp peak to 55.4 m/s @ 23.90hz, then sharp drop to 35.6 m/s @ 25.69hz... almost vertical drop from there..

That's w 6 4" PVC @ 40" each.. I definitely have the room, box is 46.5" x 19.1" x 16.5" internal..

Will displace about the same as a single slot port..

A single slot port, 6" x 19.50" x 57.76 will peak out at 35.6 m/s @ 24hz. While this is much closer to ideal as per your suggestion, I will need a friend to help build that..

Not sure how much internal volume it will displace.. Bare bones box without bracing, port or sub displacement measure just over 8.5 cf!!

I'm just not sure if I'm calculating properly.. I plugged in 8cf for displacement..

What is the correct procedure for inputting data? I've got a bare box, no subs or bracing yet, no port..

As internal dimensions diminish with displacement, this gives me an obvious change in port length..

How is the input of data correctly done?
 

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You need to basically shoot the moving target.

In other words, you're best off doing plans several times, taking the calculations into consideration. For instance, find the displacement of your ports (break out your math for cylinder volume). I actually use SketchUp all the time for this. It gives square area of a given space, and then I just multiply by height. I can also use plugins for volume with "weird" shapes. But you can do this on paper as well. For instance, 3.1416 x radius squared x height, and on a 4.5" (outside diameter), it would go like this:

2.25^2 = 5.0625
x 3.1416 = 15.904
x 40" = 636.174 cu inches displaced. And then x6 for four ports, and you get 3,817.04 cubic inches, which is 2.2 cubic feet of displacement.

Which is one reason when I modeled your stuff, I tried using 7 cubic feet instead of ~8.

Now unless I have incorrect specs (not sure about that), I modeled these subs again (on my new laptop computer, ergo new software), and I calculate you'll be able to get acceptable velocities with 3 4" vents. Again, using an infrasonic filter (18hz in this sim), and I'm using 1000W total power, this reduces the velocity at the very bottom end, and it keeps the sub out of excursion limits. If you go with 4 vents, port velocity drops down into very acceptable limits, likely not audible even at full boogie. For instance (again, guessing box size around 7 cubic feet final), 4 vents would be at 27.91" and 3 would be 20.2". That will end up being much less displacement due to ports, giving you a bigger box overall. IMO, if you can swing it, go with the 4 vents and the reason is, even if you don't flare the ports or anything, you're likely not going to hear much port noise if any. 4 vents with this size would turn out to be a tick over 1 cubic feet of port displacement, at 1.027 or so. Remember your bracing should be extensive with subs like this, but that shouldn't take up too much space. You can "buy" some space back by using Polyfil or other kinds of batting-type stuffing. The jury is out on how much space you can pretend to increase with, but my recommendation is to line the box heavily just to reduce impedance even if you don't need the space.



Have fun, be safe!


Oh and if my numbers aren't adding up, throw me the specs of this driver, I'm using WinISD's W12GTi specs but they may have changed over time.
 

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Discussion Starter #37
You need to basically shoot the moving target.

In other words, you're best off doing plans several times, taking the calculations into consideration. For instance, find the displacement of your ports (break out your math for cylinder volume). I actually use SketchUp all the time for this. It gives square area of a given space, and then I just multiply by height. I can also use plugins for volume with "weird" shapes. But you can do this on paper as well. For instance, 3.1416 x radius squared x height, and on a 4.5" (outside diameter), it would go like this:

2.25^2 = 5.0625
x 3.1416 = 15.904
x 40" = 636.174 cu inches displaced. And then x6 for four ports, and you get 3,817.04 cubic inches, which is 2.2 cubic feet of displacement.

Which is one reason when I modeled your stuff, I tried using 7 cubic feet instead of ~8.

Now unless I have incorrect specs (not sure about that), I modeled these subs again (on my new laptop computer, ergo new software), and I calculate you'll be able to get acceptable velocities with 3 4" vents. Again, using an infrasonic filter (18hz in this sim), and I'm using 1000W total power, this reduces the velocity at the very bottom end, and it keeps the sub out of excursion limits. If you go with 4 vents, port velocity drops down into very acceptable limits, likely not audible even at full boogie. For instance (again, guessing box size around 7 cubic feet final), 4 vents would be at 27.91" and 3 would be 20.2". That will end up being much less displacement due to ports, giving you a bigger box overall. IMO, if you can swing it, go with the 4 vents and the reason is, even if you don't flare the ports or anything, you're likely not going to hear much port noise if any. 4 vents with this size would turn out to be a tick over 1 cubic feet of port displacement, at 1.027 or so. Remember your bracing should be extensive with subs like this, but that shouldn't take up too much space. You can "buy" some space back by using Polyfil or other kinds of batting-type stuffing. The jury is out on how much space you can pretend to increase with, but my recommendation is to line the box heavily just to reduce impedance even if you don't need the space.



Have fun, be safe!


Oh and if my numbers aren't adding up, throw me the specs of this driver, I'm using WinISD's W12GTi specs but they may have changed over time.
OK, so here's where I'm at.. Again, I have very limited prior experience with box building/woodworking, I'm on a super limited budget, I am working on the street with cheap tools which I had to "rig"

Trouble with 4 or even 3 4" vents if lack of room..

I am posting pics, but I will try to draw something up which better illustrates the hurdle I'm faced with..
 

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Discussion Starter #38
Box is 48" in wide, will be approx 20 deep, is 18 high (external) subs will mount on face, with all the internal bracing, depth of subs, narrow height, (top to bottom) I am faced with a few problems..

A) Can't get all 4 ports to fit from one side
B) Can't run ports on either side (box is wedged snug against passenger side of rear, on the drivers side, there's a cavity which has room enough for ports to breath..

I can manage 3 on the driver side ( I think) however, the ports will not be even with subs inside box.. Will this matter?

Also, if I decide to run from front or back of box, I'll need 90' bends, still haven't mastered the calculations for that yet..

Also, I wanted to point out, those are 4 x 6s cut to triangles.. I started with 5.25ish blocks (cut board into perfect squares, then ripped those into triangles, there are +/- 1/8" variations)

the two vertical strips along the back walls are 3/4" ply, obviously installed with the strong end against the back wall (exposed ply ends are secured to back wall)

the center brace is a pair of 3/4" plywood boards glued together, measure 2.5" in width, plenty strong..

triangles measure 5" x 5" x 7" x 3. 75 " (ish)

('m pretty sure I have plenty of bracing for the back of the box, as for the front, because I have the thick center brace, as well as doubled up 3/4" ply for face where subs will mount, I don't think I'll need to duplicate the rear.. I will reinforce the edges of the front where the face mounts using strips of 3/4" ply, this should be plenty strong..

If you see anything wrong with the way I've braced everything, please let me know!!

What are some other options for porting?

Could I go in from front and use 90' bends? If so, could you help with calculations?

Also, I've gotten proficient enough with use of jigsaw, also picked up router with circle jig..

They sell large cardboard cylinders for the purpose of building concrete foundations for light projects (decks, sheds etc) If memory serves correct, the cardboard is treated for moisture, reinforced, super sturdy (thick) and is something in the neighborhood of 10" diameter? (going by memory, it's been so many years)

Basically, I am no longer limited to 4" round ports, also, 4" round ports are really not to viable an option at the moment..

Any and all suggestions greatly appreciated.. Thanks in advance!!
 

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I think you'll be just fine with a total of (4) 4" ports.

I just modeled it myself, 7.5 cuft box, 25Hz tune. With 1000 watts of system power, air velocity peaks at 29m/s at 23Hz. With 2000 watts, it peaks at about 41m/s, again at about 23 Hz. In that alignment, response models great, flat to 25Hz and -3dB at about 21Hz. Most music, even modern electronica, rarely reaches much lower than 25-30Hz.

Cone excursion also looks good in that model, they'll stay below xmax at 1000 watts until 21Hz. With 2000 watts, they'll exceed xmax once at 35Hz by only about 1-2mm, then again at 22Hz and below.

Keep in mind, you'll rarely reach full system power with typical music listening unless you just crank the shit out of it on a regular basis. So, both excursion and vent air velocity will stay well below these limits most of the time. Also, if you have the capability of a highpass on the subs, that will also help tremendously with keeping the excursion and vent air speed in check.

As an example, I use 2 W15GTIs in my home theater. The box is 20cuft with a 17Hz tune, powered by pro amps currently capable of 750 watts per driver. There are (2) 4" ports and they are located at the ends(sides) of the box along with the woofers, so (4) 4" vents total. I used a large(2") round over bit in my router to ease the end of the port at the baffle to help with any chuffing. Modeling this without a highpass in place, I exceed xmax once at 25Hz and then again at 15Hz. According to WinISD, my vent velocity reaches 27m/s at 20Hz, 25m/s at 18Hz, 40m/s at 17Hz and finally peaks 49m/s at 15Hz.

With a highpass at 15Hz, vent velocity peaks at 35m/s at 16Hz. Xmax peaks twice by 2-3mm, once at 25Hz and then again at 13Hz where it drops off again due to the highpass filter in place.

I never hear any chuffing what's so ever. The only time I hear the woofers struggle a bit is when I'm cranking it and the amplifiers start clipping. Again, this is in a house and a room that is waaaaaay bigger than the cabin of a car and in a box tuned lower and bigger than these woofers are meant to be in. I think your 7.5cuft box with a 25Hz tune and (4) 4" ports would be excellent.
 

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Discussion Starter #40
I think you'll be just fine with a total of (4) 4" ports.

I just modeled it myself, 7.5 cuft box, 25Hz tune. With 1000 watts of system power, air velocity peaks at 29m/s at 23Hz. With 2000 watts, it peaks at about 41m/s, again at about 23 Hz. In that alignment, response models great, flat to 25Hz and -3dB at about 21Hz. Most music, even modern electronica, rarely reaches much lower than 25-30Hz.

Cone excursion also looks good in that model, they'll stay below xmax at 1000 watts until 21Hz. With 2000 watts, they'll exceed xmax once at 35Hz by only about 1-2mm, then again at 22Hz and below.

Keep in mind, you'll rarely reach full system power with typical music listening unless you just crank the shit out of it on a regular basis. So, both excursion and vent air velocity will stay well below these limits most of the time. Also, if you have the capability of a highpass on the subs, that will also help tremendously with keeping the excursion and vent air speed in check.

As an example, I use 2 W15GTIs in my home theater. The box is 20cuft with a 17Hz tune, powered by pro amps currently capable of 750 watts per driver. There are (2) 4" ports and they are located at the ends(sides) of the box along with the woofers, so (4) 4" vents total. I used a large(2") round over bit in my router to ease the end of the port at the baffle to help with any chuffing. Modeling this without a highpass in place, I exceed xmax once at 25Hz and then again at 15Hz. According to WinISD, my vent velocity reaches 27m/s at 20Hz, 25m/s at 18Hz, 40m/s at 17Hz and finally peaks 49m/s at 15Hz.

With a highpass at 15Hz, vent velocity peaks at 35m/s at 16Hz. Xmax peaks twice by 2-3mm, once at 25Hz and then again at 13Hz where it drops off again due to the highpass filter in place.

I never hear any chuffing what's so ever. The only time I hear the woofers struggle a bit is when I'm cranking it and the amplifiers start clipping. Again, this is in a house and a room that is waaaaaay bigger than the cabin of a car and in a box tuned lower and bigger than these woofers are meant to be in. I think your 7.5cuft box with a 25Hz tune and (4) 4" ports would be excellent.
Thanks so much for info!

My problem now is getting 4-4" ports to fit.. I will have to mount ports front or back

original plan was 2 per side, with each sub offset for clearance issues.. in other words, if you're looking at the subs mounted, one will be mounted top left corner, the other bottom right. 2 ports to a side, mounted horizontally..

so the left side of box will have sub mounted near top, if you look on the actual side of the box, the left side would have ports mounted low, both mounted side by side horizontally.. Inside the box, the ports will just clear the left side sub, extend all the way to the right side of box, vice versa and opposite mounting for right side of box, ports mounted horizontal at top, extending into left side sub area, and sub mounted low in box.

That is the only way I can mount these subs in this box with 4-4" ports tuned to 22/24hz (clearance issues with subs and bracing..)

Summary, two ports per side, left side ports mounted horizontally on bottom beneath sub, extending all the way into right side of box.. Right side ports mounted horizontally at top of box above sub, reaching all the way into left side of box (right side sub mounted on bottom of box)

I could port through front or back, 90 degree angle, but I'm not entirely sure how to calculate port lengths divided by elbow, not sure what to subtract from displacement for elbows..

Passive radiators are sounding real simple and worth the expense at this point!!

I have yet another option..

I own a pair of BNIB JL Audio 13W3-V3-8 subs.. I can sell the pair of JBL, purchase two more of the JLs, effectively giving me 13" x 4 cone/surface area with a total of 2600 watts RMS power handling.. Frequency response 22hz and up, 600 watts RMS single 8 ohm voice coils each.

These are the latest JLs, black cone..

Thoughts?

Also, love that you're a home theater enthusiast!! I have all Adcom amps, high end Pioneer receiver with the latest surround tech, 24 bit Burr Brown DAC on all channels, have a pair of 15" JBL 2226HPLs in 8CF tuned to 32hz, 1000 watt Crown amp on JBLs..

Mirage mains center and surrounds, Adcom GFA 555 MKII on the mains, 5 channel Adcom on center and surrounds.. (100 x 5 @ 8 ohms)

Pioneer/Adcom sound amazing (entry level audiophile is all I can afford, Adcom best bang for the buck)

the Mirage speakers are the weak link..

When I sell my townhouse, I'll get a pre-owned JVC projector (I forget the model number) a few years back when I worked for home theater installs, this particular projector was $7000.. They now sell used for under $1000.. It's more than I'd ever need..

One of the showrooms which featured this projector had an 8' x 12' screen (if memory serves correct) I watched King Kong, the contrast and detail on the black and dark colors was astounding, the glimmer in his eyes on closeup, no jitter or rainbowing, just amazing what this tiny projector is capable of..
 
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