Understanding Port Length, Box Volume, and Tuning Frequency.

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In this video I provide examples of how box volume, tuning frequency and port cross section impact the length of your subwoofer's port. Watch this video and you will understand everything that determines your port length.

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Chapters:
0:00: Box Volume vs Port Length
5:48: Tuning Frequency vs Port Length
9:01: Port Cross Section vs Port Length
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[ashleymalone]

THIS is where I need to expand my knowledge. Good info.

[mikewhite]

Fantastic video. Best one I've found explaining the difference. I've built alot of boxes and had to just learn by trials and errors. This is badass.

[td]

I'm about to build my first enclosure for a SQL-12. Your explanations and use of WinISD is exceptionally helpful. Thank you for explaining so clearly, it makes me less nervous about building my own.

[gsxroyce]

At the 5 min mark, where we see the sub over extending, if you move the tuning frequency up from 28 to 35, to put that dip where the sub don’t move much at the tuning frequency, would that eliminate over excursion on the 4qf box? Edit/ NM you answered that at the 8:15 mark. My bad I should’ve just kept watching lol

[ReferenceFidelityComponents]

A few things: turbulence occurs well below 18m/s, more like 11m/s. Size of port may not influence transfer function in CAD but the realty us that it will increase impedance coupling efficiency with the room air mass which is beneficial. Rule of thumb is to use a port area approx 30% of the area of the driver. You loose port efficiency and alter system Q by using folded line ports compared with port tubes with or without elbows but straight vents are fine. Experienced designers know that box calculators over simplify the expertise needed to maximise SQ, system efficiency and to more accurately design and tune a vented system which ideally also includes system impedance testing.

[feedrate]

Love all the hard work you put in to your channel. Definitely one of my favorite channels!!🤘🤘🤘

[gordythecreator]

Your explaining exactly what I've been HEARING for years now. I didn't want to figure out the formula for myself, and I assumed someone had already done that

[Bassotronics]

Another thing to note is depending on where there port opening finishes (near the enclosure or far from the enclosure) will also affect tuning despite the length due to different frequencies having different wavelengths. Port location is also crucial to the overall frequency response.
(Phasing).

[sveneisenhauer]

Ah, finally a tutorial that puts this into better perspective. Thanks! Now, please also build the boxes and show us and you’ll have friends forever...! 🤗😇

[reverbae]

Hey My Prefab Subwoofer Box Tuned At 35Hz Is It Good If Not How To Get It More Lower I Am New At This Please Help😊

[preston]

I've watched this video like 6 times while making my first box. Thank you

[FireMedic]

I used this video and 2-3 others to build me a dual vented, dual 12” enclosure. First slot vent I ever built and it is superb. Winisd came in clutch.

[gsxroyce]

I’ve always build my own boxes but never knowing what I doing lol. But always got lucky. I build a box for a single 18 evl Skar. It was 3qft with 8” round port that was 23” long and was 3” from the back of the box. It peaked sub at 50hz. I left it alone bc l don’t know what to do and it sound fine so it was what it was. It could’ve been a lot better now that I’ve seen this

[RandoManFPV]

Laughing so hard at the types of answers I get when going to Google for audio info.
I searched "is cold weather bad for your subs?"
Here's what I found lol:

*How do you warm up subs?*

take the top off the sub, put the sub on some aluminum foil, turn your oven on broil, put your sub in the oven for like 3 minutes (just stay close by, you'll smell when it's done depending on how much stuff is on your sub), remove sub from oven, reconstruct, devour

[drywater_]

I remember spending months teaching myself this stuff back in highschool. Wish you were around back then lol

[agghell]

I was looking for a port explanation and i found it. New subscriber here !!!

[HighVybeTribe]

i have seen plenty of subwoofer box builds where the port is external . Matter of fact a 1 cu ft enclosure for a 10 " sub with a 3inch Aero port about 10 " long

[evrenodabas]

hello i have cervin vega wmax 15.2 and i couldn't manage to make a box for it can you help me thank you so can you make me a box sizer

[Roof_Pizza]

Combining cubic feet and inches with meters per second. Americans.

[MilesPrower]

im quite dyslexic and when i designned my box in some rando software for the net i accedentally set my speaker magnet volume to be a few cubic feet, my 1.5 sq ft box ended up being nearly a 4 foot box, i made 2, and boy howdy did it hit those lows hard, haha