@@DIYAudioGuy yeah for sure. We all know that there are Lot's of SPL guys hitting one note at their peak but aside from that stuff I haven't seen much about finding a nice low tuned box with a reasonably sized port area to keep port noise to a minimum. God willing I can sell something or get a good side job that'll enable me to buy this nice custom box with a level 4 DC Audio 12" sub included with it. ,* Thinking about doing something similar to my last car audio build with a 12" in a better box than last time, and a 15" in bigger & lower tuned box then at least one set of decent 6x9's in those little sealed boxes plus the fairly good speakers already in the factory locations for mids and highs. *Too bad I didn't have a really good way I can think of to mount the 6x9's in something bigger cause I've seen some amazing sounding 6x9's mounted in the back deck of a Ford escort hatchback and even some mounted in the rear deck with the trunk as the enclosure.. I just might have to build some slightly larger sealed boxes for them maybe on each side of the rear seat of my first generation Grand Cherokee I just picked up. Guess it all depends on if I can make the Extra approximately $300 for everything from the 12" and custom box, a Little package deal with a couple of good full range amps and a box with dual 10"s I believe etc, and then the pair of 6x9's for some nice and solid mids and highs.. getting most of this stuff used, plus still having some things I just couldn't include with the car and system I sold my Buddy!!
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
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...! 🤗😇
Holy moly. My head is about to explode! I'm going back to your oscilliscope video to make sure I am doing this correctly so I don't damage anything. Thank you again for all the incredible information.
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).
I like that, very important. Probably equally as important as positioning of the sub, and port too I would think, i.e. sub parallel to the rear door of a minivan or SUV etc..
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.
Excellent explanation. I have read up on velocity V excursion a couple times and vaguely understood it, but your presentation of the sketchups and graphs really solidify the principles in my mind. I am indebted to you sirr thank you:)
Years ago (90s) when I had a Fiero our local audio shop placed a JL Audio 10" in the front trunk and vented it through the passenger side floor. The way this video starts kind of makes sense to me now how they did it. It was a very custom job back then and might even be considered so today. To look in the front trunk all you would see is a box as the sub was inside firing into the port area.
Greeeeeeaaat video. I build some cabinets for the first time using ESI (extra spacial intuition - i.e. guesswork :) and found them to be surprisingly close to what I needed. Didn't take air velocity into account though. Or a bunch of other things. But your explanation helped me understand what I'd done, and how to tune them better. Thank you!
Group delay is important if sound quality so important to you. Ported will always have bigger GD than sealed but they can sound good if you spend the time with design software getting it dialed in
Thanks in advance for my previous question I built a box for two X8 V4 and I missed my mark, only by 0.1 on the net box volume, but I severely missed the Port length, it's tuned to about 25 hz I was shooting for around 33 hz, I can shorten the port but that makes me miss my 2 cube net box, end result will be close to 2.3 net 33 hz, Love the videos I learn a lot from your content
They both have their place. I don't post a lot of videos about sealed enclosures because they are simple to design and build, and don't require a lot of technical knowledge.
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
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
So I think the 3 years passed has probably changed the concept of the ‘too small’. The folding of the port is from my observations is really practical. Thanks for all the info, but every time you say ‘is very impracticle’ I think: no it’s very easy to fold the port in.
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.
Thanks for all your hard work and detailed efforts! Great stuff, and supersized knowledge boosters! I want to know if you build boxes for sale? I really don’t think I have a shop in my city that does your calculated and measured technique and approach for boxes. And I really would like another tuned box for my next two cars audio systems.
What would happen if you take the 1ft cube box and make the vent "snake" on the outside of the box. Like a T Line box, add lots of 90 degree bends on the port, outside the box, to compact the overall length of the port and make the overall size of the box more compacted. I hope that makes sense.
@@DIYAudioGuy Does the 90 degree bends have an effect on the airflow in the same way as 90 degree bends in a hydraulic system, or bending a wire 90 degrees will increase resistance?
@@turboduckhead6179 to be perfectly honest, I don't know. It seems like it's done a lot and it seems like it would restrict airflow but I'm not aware of any testing or evidence to prove that it does or does not have an impact on the sound. If lumber prices ever fall I might have to build a box and test that out.
Hey! So I need to make a custom sub enclosure to go under the back seats of my truck... How do I go about sizing a sub and tuning the enclosure? My starting point would be to make the custom box the max size possible.. from there I will know the cu3 capacity of the box.. with that information how do I then size a sub for that box?
I offer design services. diysubwoofer.blogspot.com/2021/05/custom-subwoofer-enclosure-designs.html I don't build boxes, the shipping cost is just too high.
I have been digging into that, trying to find a formula that will tell me when a wood panel of a given size will resonate. I have yet to crack the code.
What impact does the use of an enclosure wall for the structure of a vent actually have on the effective vent length and subsequent enclosure tuning frequency? In my experience, it marginally but measurably lowers the effective tuning frequency where the total vent area is less than 12-15 square inches. Maybe I'm just splitting hairs..
It makes the effective length of the port longer by the width of the port. So if you have a 3-in wide port, you need to make your port 3 in shorter in order to hit your tuning frequency.
@@DIYAudioGuy Yea good vids, decent informed opinions. I like it. At least you're not throwing random drivers in random "kit boxes" disregarding T/S params like some home theater channels out there!
1:03 Ive wondered about ports that are that small. If you can have that 4cu volume would that port be good or would it act more like a leaky sealed box?
I put the ports outside of the box just to make it easier to see. As long as you account for the airspace taken up by the port so that the net airspace is the same, the tuning will be the same. Hope that makes sense.
Does the shape of the box affect the tuning? I want to build a single 15" box at 3.5 Cubic ft but the dimensions I have seen online are too deep to fit in my vehicle. If I make I take an inch off the depth and make it an inch taller, would that affect a lot?
How do you calculate your port when you have two subs sharing the same airspace? I've got an odd shaped console where it would be easier for calculations to just share space.
Can a 10 inch cutout hole on a 10 inch subwoofer enclosure be enlarged to fit a 12 inch subwoofer if so will it be a tight fit for the subwoofer and cause the subwoofer to not sound the best.
Can you plug a big 15 inch high powered active subwoofer that has a plate amplifier with 1000 watts of power consumption into the 120 volt ac outlet on the back of a home theater receiver
Like at 2:10? That's the f3. It is a way of quantifying how low a subwoofer can play. There is not much output from the sub when it plays lower than the f3.
What about round flared plastic ports? Like say a 3in diameter tube with a flare that's 12 in Long in a 2ft cu box? So if you were to drill a couple 3 in Holes and add the flared plastic parts of a certain length? Would that work?
If you enlarged a 10 inch cutout hole on a 10 inch subwoofer enclosure to fit a 12 inch subwoofer into the enclosure would you suffocate the subwoofer itself or possibly block the vent on the back of the subwoofer itself if the subwoofer ends up getting mounted into the enclosure itself after enlarging the cutout hole.
I plan to do blutooth speaker with no port instead with 3 passive drivers it's gonna handle 40 watts 4 ohm 5 inch woofer and 2 tweeters ,do you think passive drivers make up for no port?
I have a Ford Maverick where my box size will be .5 cubic feet, looks like I'm running PVC boom tubes out the box and pointing them in the direction of the woofer...
How does one figure out loading wall tuning on a 6th order wall. Typically you see just an opening that is essentially only as deep as the wall itself. I never understood how to figure that out.
Those big SPL builds like that are a lot of trial and error. One reason why those huge porters of short is because the enclosures themselves are massive. Take up the entire vehicle, that kind of thing. I don't have any experience with it so I couldn't tell you much more.
@@DIYAudioGuy i believe theres some sort of enclosure size to port area size ratio that gets figured out with a mathematical formula but i cant find much more on what formula is used so i typically rely on applications but i worry ill enter things wrong with this kind of port design
I understand the ports are external for visual reasons. But once you put the port inside does that change the internal volume, thus changing the required port length?
Do you think its important to include the air volume into the displacement of the box? I have added the material volume for probably 15 years, but with playing with a new program it includes the air volume too. Love your input. The application is car audio heavy bass
@@gunlover7851 The airspace in the pork is separate from the airspace in the enclosure. Most subwoofer enclosure calculators and software don't include the port in the airspace.
If you were to plug up the port on a subwoofer enclosure with a giant cork to make it a sealed enclosure will the giant cork get blown out of the port if you crank up the volume really loud and if the subwoofer is getting a lot of power
Ive learned loads these are great videos!! 🙏 Does it matter if the port extends out of the box?? Im building the box for structural sound but im constricted a little with space so would be ideal to make the port longer for obvious reasons, im going to fibreglass over top wich will hide it all and look awesome in the boot of my car for the end design i have in my head.
There is a lot of debate on that question -- how far can the port be away from the driver, which direction should you face the port relative to the driver? I am firmly in the "it does not matter much at all" camp. The wavelength at 100hz is over 12 ft. Which is longer than the cabin on everything but the largest SUV's and vans. So if you are in a typical car trunk I don't think it will matter as much as the placement of the sub and port in the car.
@@DIYAudioGuy ok thanks, the box(x2) will have to be 0.02 cubic inch with an 8inch inverted sub. I used the Precision Sound calculator that u mentioned but its a ridiculous amount of port length even for 40 hz so im assuming ill still get that kick from it? But just no real low frequency that im after. Just worried about damage on the drivers thats all.
@@ashleykellow5657 Yeah although most all of the sub amps I have had in the last probably 15 years or so have had subsonic filters, I much rather have the box tuned low enough to either not use the filter or have it turned to like 25hz
There's no simple answer to that question. Once upon a time the exact same drivers were used in all three applications, and even now a normal everyday subwoofer can be used in any of those applications. But SPL competitions gave rise to subwoofers design to handle a lot of power, but they're not very efficient. So on the same power those are not as loud as a PA subwoofer. But they can play louder because they can handle a lot more power. That is the short version.
Amazing info, I had planned on physically building some of these boxes to verify the differences. My question is at what point should you decide to have a chamber at all. In example I built a 12 ft front loaded single fold tapered horn for truck blow through build. It's about 29hz tuning fq. I'm wondering now if I should have built it with some chamber to help load it at the higher frequencies. I'm going to have a bunch of questions for you in the near future, look forward to your wisdom. 👍🔊✌
To large of a box causes over excursion for sure. I think lining the walls of the box with Poly fill can help with this some. I am going to probably test this today since I’m going to be building a box similar to box 2. For a 12” alpine. Calls for 1.75 cu ft for ported box but I think I’ll build around 2 cu ft to about 30-32 hz. Going in a trailblazer. I just can’t decide if I should go with sub up or back. I think I’ll do both port and sub facing back.
Test it out and see how it works. A lot of people think that a box sounds better with some kind of stuffing, if nothing else it will help with standing waves.
@@DIYAudioGuy I usually use it because of to small of a box just working with what I had already. Ive never liked the sound when the box is stuffed full. I have had good success using blanket style poly and using adhesive spray on the walls and applying a 1/2”-3/4” layer. Of course this also keeps it in place in ported boxes eliminating the small chance of anything going into the coils.
It is based on how you want to use the speaker and the driver you choose. A home theater sub is typically tuned much lower than a car sub. A 6" driver in a bookshelf speaker is tuned even higher. I model the response in WinISD and use that to guide my choices. ruclips.net/video/yZNeYBYGRKk/видео.html
@@DIYAudioGuy does the speaker's specs have anything to do with the tuning frequency? i dont get it.I assume that I dont tune a box lower then the driver can produce and I wouldnt go alot higher then the driver produces, but I am new to speaker building. Is there a bump where the box is tuned?
@@jalang63 yes, but it's a complex interplay of the parameters with the enclosure. So I just use free software to do it. ruclips.net/video/yZNeYBYGRKk/видео.html
So I put a 4in round port on my box with a 15in sub ......the port has a 45degree corner piece , it measures 12inches to that corner piece, to the lowest point of port measures approx 15 inches ....3.3 cu ft , box is made with 1.5in conference table, sub is black brick audio, anyways my question is if I were to put another 4in port next to the other one, chop off the angle piece, how long would each port need to be? The correct port length for what I'm trying to get (31hz)is 7.75in with a single,so would 2 4in ports be about 4in long or 14in?
Hello, i have a Ground Zero GZCS 10SubAct and I was really disappointed by the poor bass quantity, I would like to install a funel port but I don’t know the placement or the length that would be needed.. any help from someone ?
@@DIYAudioGuy I'm about to do a different build and go with 1 15 in the middle of my single cab and thinking of doing 2 ports one on each side facing up. Or just use 1 on the passenger side to help with loading?
Let's say I'm ok with the physical dimensions of the box with a longer and larger overall cross section port, at what point does air velocity become a problem on the lower end of your chart @11:33 time stamp? Example: Manufacturer calls for a single 4" round port 11" in length for a 12" subwoofer in 2.0 cuft. I'm considering two 6.5"x1.5" slot ports 20" in length on either side of my design.
For sound quality you want to keep the port velocity below 17 m/s. You can get away with more for an SPL build (as much as 30 some say). Flared ports should let you double that number.
I have two massive audio subs. spec rating on paper is not true, so I contacted massive audio and they told me 4.0 cubes and a 30 square inch port... My question is should I make an open air box with bracing or cut the specs they gave me in half for two separate chambers?
It should not make a big difference. If it were me I would go with the large single chamber just because it'll be easier to fold one port into the box instead of two, and that one port will be a little bit shorter. One thing I learned on the home theater build that I just completed is that you really can't go overboard on the bracing. I would definitely put a brace down the center from the baffle to the back wall/port wall in addition to bracing across the width of the box.
I'm also glad to hear that the manufacturer recommended a nice large port cross-section like that. After modeling and building a few enclosures I've learned that ports need to be as large as possible.
@@DIYAudioGuy hey thanks for getting back to me so fast {comma} I talked to a couple other guys and they said those are great specs I just need to design an enclosure that fits them LOL. Having some breakthroughs recently too, and that makes the next thing easier to understand so port calculating is next thank you again.
Always ignore the max power (maxxpoweraudio.com). I model with 80% power in WinISD because in the real world you have to deal with box rise, power factor, and low voltage. So you it is very hard to get the full RMS power out of an amp.
@@DIYAudioGuy i have the sinbosen fp14000 for my subs, i have the fi audio neo 3.5. I do appreciate your channel and feedback I like learning from the pro's
If you took a 15 inch pro audio dj subwoofer that has a frequency response range of 40 hertz to 2000 hertz and slapped it into a prefabricated 15 inch car audio subwoofer enclosure that is tuned low around 25 hertz will it still hit low and still produce deep bass.
Question: How long should my 2 8inch aero ports need to to be for my 14cft box? I'm installing 3 Resilient Sounds Team 18's subwoofers in it and i want to tune it to around 32 to 35hrz. Please help me, thanks👍
Excellent very informative!
Glad it was helpful!
@@DIYAudioGuy hello sir can I ask for your suggestion box for a Groundzero GZIW 12 SPL to make it hit lower bass.
THIS is where I need to expand my knowledge. Good info.
You're just aren't a lot of videos out there that explain this.
@@DIYAudioGuy yeah for sure. We all know that there are Lot's of SPL guys hitting one note at their peak but aside from that stuff I haven't seen much about finding a nice low tuned box with a reasonably sized port area to keep port noise to a minimum.
God willing I can sell something or get a good side job that'll enable me to buy this nice custom box with a level 4 DC Audio 12" sub included with it.
,* Thinking about doing something similar to my last car audio build with a 12" in a better box than last time, and a 15" in bigger & lower tuned box then at least one set of decent 6x9's in those little sealed boxes plus the fairly good speakers already in the factory locations for mids and highs.
*Too bad I didn't have a really good way I can think of to mount the 6x9's in something bigger cause I've seen some amazing sounding 6x9's mounted in the back deck of a Ford escort hatchback and even some mounted in the rear deck with the trunk as the enclosure..
I just might have to build some slightly larger sealed boxes for them maybe on each side of the rear seat of my first generation Grand Cherokee I just picked up.
Guess it all depends on if I can make the Extra approximately $300 for everything from the 12" and custom box, a Little package deal with a couple of good full range amps and a box with dual 10"s I believe etc, and then the pair of 6x9's for some nice and solid mids and highs.. getting most of this stuff used, plus still having some things I just couldn't include with the car and system I sold my Buddy!!
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
That's cool!
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.
I've watched this video like 6 times while making my first box. Thank you
Glad to be of help.
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...! 🤗😇
That is definitely in the works! Just waiting on the time and the money to do it. In the meantime:
ruclips.net/video/dbVd5igcjHs/видео.html
Holy moly. My head is about to explode! I'm going back to your oscilliscope video to make sure I am doing this correctly so I don't damage anything. Thank you again for all the incredible information.
Glad to help.
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).
Yeah, there is a lot more to it! I need to build some boxes and take some measurements!
I like that, very important. Probably equally as important as positioning of the sub, and port too I would think, i.e. sub parallel to the rear door of a minivan or SUV etc..
I remember spending months teaching myself this stuff back in highschool. Wish you were around back then lol
I was around, I was just not making videos.
One of the best explanation in one of the most simplest words .. Thank you so much
Glad it was helpful!
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.
Excellent explanation. I have read up on velocity V excursion a couple times and vaguely understood it, but your presentation of the sketchups and graphs really solidify the principles in my mind. I am indebted to you sirr thank you:)
You are welcome.
I was looking for a port explanation and i found it. New subscriber here !!!
Years ago (90s) when I had a Fiero our local audio shop placed a JL Audio 10" in the front trunk and vented it through the passenger side floor. The way this video starts kind of makes sense to me now how they did it. It was a very custom job back then and might even be considered so today. To look in the front trunk all you would see is a box as the sub was inside firing into the port area.
That sounds like a bandpass.
Got a lot out of this and right on time for my latest build. Thanks
Glad I could help!
Another excellent video, thanks for taking the time to explain this in terms pretty much anyone can understand. We are always learning!
Glad it was helpful!
Greeeeeeaaat video. I build some cabinets for the first time using ESI (extra spacial intuition - i.e. guesswork :) and found them to be surprisingly close to what I needed. Didn't take air velocity into account though. Or a bunch of other things. But your explanation helped me understand what I'd done, and how to tune them better. Thank you!
Thanks!
Love this video, watched it many times.. to make sure i understand this.
Thx DIY dude ;)
Glad it helped!
Me after this video: I KNOW KUNG FU!!
🤣
None sense.😢
Neo! 😂
Show me
@@rowlesorama This is a sparring program!
Xmax is the reason why i go 3 or 6 db below the max this works very well and over 100db is a good trade off for sound quality
👍👊
Group delay is important if sound quality so important to you. Ported will always have bigger GD than sealed but they can sound good if you spend the time with design software getting it dialed in
Thanks in advance for my previous question I built a box for two X8 V4 and I missed my mark, only by 0.1 on the net box volume, but I severely missed the Port length, it's tuned to about 25 hz I was shooting for around 33 hz, I can shorten the port but that makes me miss my 2 cube net box, end result will be close to 2.3 net 33 hz, Love the videos I learn a lot from your content
I’ve watched numerous videos on this channel, and I definitely get the feeling he doesn’t like sealed enclosures
They both have their place. I don't post a lot of videos about sealed enclosures because they are simple to design and build, and don't require a lot of technical knowledge.
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
Damn this gets technical making my first ported box wish me luck
My friend made a 4×4 Bass Box and you can hear his Bass coming mile away ! Thunder!!
Thanks alot, I'm starting to understand alot more !!
Glad to help.
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
So I think the 3 years passed has probably changed the concept of the ‘too small’. The folding of the port is from my observations is really practical. Thanks for all the info, but every time you say ‘is very impracticle’ I think: no it’s very easy to fold the port in.
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😊
That is probably just fine, but it will depend on your subwoofer. If you are happy with the sound then don't change anything.
@@DIYAudioGuy i don't have Subwoofer i had woofer 8"
60w 8ohm
@@DIYAudioGuy but i wanna go more lower so tell me how to do that
Excellent videos. Just discovered your channel, glad I did !! Thank you.
Welcome to the party!
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.
Glad it was helpful!
Sono stanco di essere preso in giro da te e il tuo compare 🌇
Thanks for all your hard work and detailed efforts! Great stuff, and supersized knowledge boosters! I want to know if you build boxes for sale? I really don’t think I have a shop in my city that does your calculated and measured technique and approach for boxes. And I really would like another tuned box for my next two cars audio systems.
I don't. Mostly due to shipping costs.
This is a trully masterclass
Thanks!
What would happen if you take the 1ft cube box and make the vent "snake" on the outside of the box. Like a T Line box, add lots of 90 degree bends on the port, outside the box, to compact the overall length of the port and make the overall size of the box more compacted.
I hope that makes sense.
That works just fine, it's just a pain in the ass to design and build.
@@DIYAudioGuy Does the 90 degree bends have an effect on the airflow in the same way as 90 degree bends in a hydraulic system, or bending a wire 90 degrees will increase resistance?
@@turboduckhead6179 to be perfectly honest, I don't know. It seems like it's done a lot and it seems like it would restrict airflow but I'm not aware of any testing or evidence to prove that it does or does not have an impact on the sound. If lumber prices ever fall I might have to build a box and test that out.
@@DIYAudioGuy I see prices of birch has tripiled in prices since corona..
@@turboduckhead6179 fortunately lumber futures are beginning to fall. It's going to take a few months before that to translate down to retail prices.
Hey!
So I need to make a custom sub enclosure to go under the back seats of my truck... How do I go about sizing a sub and tuning the enclosure?
My starting point would be to make the custom box the max size possible.. from there I will know the cu3 capacity of the box.. with that information how do I then size a sub for that box?
What about a small box like the first one with mutliple ports?
awesome work, great information.
Instead of one long port, can you use two ports that are half the length of a single port?
I answered that question in this video. ruclips.net/video/B0cqSt3RNK8/видео.htmlsi=X_Gx7babxJU8k6a0
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
I offer design services. diysubwoofer.blogspot.com/2021/05/custom-subwoofer-enclosure-designs.html
I don't build boxes, the shipping cost is just too high.
The other thing to take into consideration is that the larger side panels can resonate, especially at low frequency.
I have been digging into that, trying to find a formula that will tell me when a wood panel of a given size will resonate. I have yet to crack the code.
genuinely helpful, +1 subscriber keep it up!
Do you think it would matter if the sub is mounted center in an enclosure versus offset? Would it affect the spl or sq?
What impact does the use of an enclosure wall for the structure of a vent actually have on the effective vent length and subsequent enclosure tuning frequency? In my experience, it marginally but measurably lowers the effective tuning frequency where the total vent area is less than 12-15 square inches. Maybe I'm just splitting hairs..
It makes the effective length of the port longer by the width of the port. So if you have a 3-in wide port, you need to make your port 3 in shorter in order to hit your tuning frequency.
A minute and a half in and I'm reminded of Goldilocks & the Three Bears.
Good one!
@@DIYAudioGuy Yea good vids, decent informed opinions. I like it. At least you're not throwing random drivers in random "kit boxes" disregarding T/S params like some home theater channels out there!
Awesome, thanks a lot!👌
Happy to help!
Do all qpower prefabricated subwoofer enclosures that are already assembled have screws holding them together.
I'm not sure. I build all of my boxes with glue and Brad nails.
Great video, thanks
You're welcome!
Im really trying to build a woofer box, and at this point have seen hours of sub box videos, yet I’m no where near to know the exact measurements.
That is a great question, join us on our next live show and we will try to give a detailed answer: bit.ly/3PYKG5P
1:03 Ive wondered about ports that are that small. If you can have that 4cu volume would that port be good or would it act more like a leaky sealed box?
I don't recommend the 4 CU FT box with the 1X12 slot port and a 10" subwoofer. It was meant to be a completely absurd example.
Does the internal airspace of the port count towards the internal airspace of the box
Nope.
Keep the giant airflow in mind!
Does the tunning change if you Put the port inside the box and why did you put the ports outside the box if that's not what normally gets done???
I put the ports outside of the box just to make it easier to see. As long as you account for the airspace taken up by the port so that the net airspace is the same, the tuning will be the same. Hope that makes sense.
Really interesting. Thanks for your explanation.
Are conical ports a thing?
Flared ports are conical.
Does the shape of the box affect the tuning? I want to build a single 15" box at 3.5 Cubic ft but the dimensions I have seen online are too deep to fit in my vehicle. If I make I take an inch off the depth and make it an inch taller, would that affect a lot?
How do you calculate your port when you have two subs sharing the same airspace? I've got an odd shaped console where it would be easier for calculations to just share space.
ruclips.net/video/B0cqSt3RNK8/видео.html
Can a 10 inch cutout hole on a 10 inch subwoofer enclosure be enlarged to fit a 12 inch subwoofer if so will it be a tight fit for the subwoofer and cause the subwoofer to not sound the best.
Yes, you can make the hole bigger, but 12's typically need more airspace than 10's to sound their best. So I don't recommend that you do that.
Can you plug a big 15 inch high powered active subwoofer that has a plate amplifier with 1000 watts of power consumption into the 120 volt ac outlet on the back of a home theater receiver
Probably not. It depends on the amp rating of the outlet.
please share this software ,
Linearteam.org
can you explain why you see some measurements on -3db what it show to us??
Like at 2:10? That's the f3. It is a way of quantifying how low a subwoofer can play. There is not much output from the sub when it plays lower than the f3.
@@DIYAudioGuy thanks
What about round flared plastic ports? Like say a 3in diameter tube with a flare that's 12 in Long in a 2ft cu box? So if you were to drill a couple 3 in Holes and add the flared plastic parts of a certain length? Would that work?
Yes, flares are great, they reduce port noise
Nice comparison 👍 informative
Thanks!
If you tuned a ported subwoofer enclosure to 100 hertz will the subwoofer still produce loud bass.
Loud, yes, very loud. Low? Not at all.
If you enlarged a 10 inch cutout hole on a 10 inch subwoofer enclosure to fit a 12 inch subwoofer into the enclosure would you suffocate the subwoofer itself or possibly block the vent on the back of the subwoofer itself if the subwoofer ends up getting mounted into the enclosure itself after enlarging the cutout hole.
Cramming a 12 into a box design for a 10 is a bad idea.
This is the same for stereo speaker box design as well, correct? Thanks !
Yes
I plan to do blutooth speaker with no port instead with 3 passive drivers it's gonna handle 40 watts 4 ohm 5 inch woofer and 2 tweeters ,do you think passive drivers make up for no port?
Yes! ruclips.net/video/v4rAkxck2_Q/видео.html
I have a Ford Maverick where my box size will be .5 cubic feet, looks like I'm running PVC boom tubes out the box and pointing them in the direction of the woofer...
What are boom tubes?
How does one figure out loading wall tuning on a 6th order wall. Typically you see just an opening that is essentially only as deep as the wall itself. I never understood how to figure that out.
Those big SPL builds like that are a lot of trial and error. One reason why those huge porters of short is because the enclosures themselves are massive. Take up the entire vehicle, that kind of thing. I don't have any experience with it so I couldn't tell you much more.
@@DIYAudioGuy i believe theres some sort of enclosure size to port area size ratio that gets figured out with a mathematical formula but i cant find much more on what formula is used so i typically rely on applications but i worry ill enter things wrong with this kind of port design
I understand the ports are external for visual reasons. But once you put the port inside does that change the internal volume, thus changing the required port length?
Correct.
Which software is used to markup the enclosures? SketchUp?
Yep! I've got a video showing how to use sketchup. ruclips.net/video/gqe0aj20u9M/видео.html
Do you think its important to include the air volume into the displacement of the box? I have added the material volume for probably 15 years, but with playing with a new program it includes the air volume too. Love your input. The application is car audio heavy bass
Not sure what you mean. If you mean the space that the subwoofer takes up and you absolutely need to include that.
@@DIYAudioGuy the air space in the port
@@gunlover7851 The airspace in the pork is separate from the airspace in the enclosure. Most subwoofer enclosure calculators and software don't include the port in the airspace.
@@DIYAudioGuy thanks brother.
If you were to plug up the port on a subwoofer enclosure with a giant cork to make it a sealed enclosure will the giant cork get blown out of the port if you crank up the volume really loud and if the subwoofer is getting a lot of power
That depends on how tight the seal is. There are some home theater subwoofers that use this principle.
I have 15" sub in a tiny car, what are my best option for low \deep base? (Polk Audio recommended for sealed box)
A great big ported box that takes up the entire trunk.
Ive learned loads these are great videos!! 🙏
Does it matter if the port extends out of the box?? Im building the box for structural sound but im constricted a little with space so would be ideal to make the port longer for obvious reasons, im going to fibreglass over top wich will hide it all and look awesome in the boot of my car for the end design i have in my head.
There is a lot of debate on that question -- how far can the port be away from the driver, which direction should you face the port relative to the driver? I am firmly in the "it does not matter much at all" camp. The wavelength at 100hz is over 12 ft. Which is longer than the cabin on everything but the largest SUV's and vans. So if you are in a typical car trunk I don't think it will matter as much as the placement of the sub and port in the car.
@@DIYAudioGuy ok thanks, the box(x2) will have to be 0.02 cubic inch with an 8inch inverted sub.
I used the Precision Sound calculator that u mentioned but its a ridiculous amount of port length even for 40 hz so im assuming ill still get that kick from it? But just no real low frequency that im after. Just worried about damage on the drivers thats all.
@@ashleykellow5657 Yeah although most all of the sub amps I have had in the last probably 15 years or so have had subsonic filters, I much rather have the box tuned low enough to either not use the filter or have it turned to like 25hz
what is this software called?
Do the speaker specs reflect on the frequency the port should be tuned to? If so what spec should we look at?
Unfortunately no.
So are car subwoofers actually louder than home audio subwoofers and dj subwoofers
There's no simple answer to that question.
Once upon a time the exact same drivers were used in all three applications, and even now a normal everyday subwoofer can be used in any of those applications.
But SPL competitions gave rise to subwoofers design to handle a lot of power, but they're not very efficient. So on the same power those are not as loud as a PA subwoofer. But they can play louder because they can handle a lot more power.
That is the short version.
Should prefabricated subwoofer enclosures be discarded after 3 years of use.
No.
Amazing info, I had planned on physically building some of these boxes to verify the differences. My question is at what point should you decide to have a chamber at all. In example I built a 12 ft front loaded single fold tapered horn for truck blow through build. It's about 29hz tuning fq. I'm wondering now if I should have built it with some chamber to help load it at the higher frequencies. I'm going to have a bunch of questions for you in the near future, look forward to your wisdom. 👍🔊✌
I don't know anything about tapered horns, soni am not sure if I can help.
Which software is this that showing all the graphs and analysis ?
WINisd
I made a video on it. ruclips.net/video/yZNeYBYGRKk/видео.html
@@DIYAudioGuy thank you
I will check that out
To large of a box causes over excursion for sure. I think lining the walls of the box with Poly fill can help with this some. I am going to probably test this today since I’m going to be building a box similar to box 2. For a 12” alpine. Calls for 1.75 cu ft for ported box but I think I’ll build around 2 cu ft to about 30-32 hz. Going in a trailblazer. I just can’t decide if I should go with sub up or back. I think I’ll do both port and sub facing back.
Test it out and see how it works. A lot of people think that a box sounds better with some kind of stuffing, if nothing else it will help with standing waves.
@@DIYAudioGuy I usually use it because of to small of a box just working with what I had already. Ive never liked the sound when the box is stuffed full. I have had good success using blanket style poly and using adhesive spray on the walls and applying a 1/2”-3/4” layer. Of course this also keeps it in place in ported boxes eliminating the small chance of anything going into the coils.
And you have a big SUV, so plenty of room for a big box with a big port.
Is there a chuffing difference between lets say
20m/s air velocity through a 4" diameter port and
20m/s air velocity through a 6" diameter port?
I honestly don't know. It should be the same.
Is there a definitive formula or correction for calculating a flared port length?
There is, but I am not 100% sure of it so I have not made a video on it yet.
So how do you avoid exceeding the xmax?
ruclips.net/video/iWRoIho7A7c/видео.html
how does a person decide what frequency to tune the box to? is it based on one of the T/S parameters?
It is based on how you want to use the speaker and the driver you choose. A home theater sub is typically tuned much lower than a car sub. A 6" driver in a bookshelf speaker is tuned even higher. I model the response in WinISD and use that to guide my choices. ruclips.net/video/yZNeYBYGRKk/видео.html
@@DIYAudioGuy does the speaker's specs have anything to do with the tuning frequency? i dont get it.I assume that I dont tune a box lower then the driver can produce and I wouldnt go alot higher then the driver produces, but I am new to speaker building. Is there a bump where the box is tuned?
@@jalang63 yes, but it's a complex interplay of the parameters with the enclosure. So I just use free software to do it. ruclips.net/video/yZNeYBYGRKk/видео.html
So I put a 4in round port on my box with a 15in sub ......the port has a 45degree corner piece , it measures 12inches to that corner piece, to the lowest point of port measures approx 15 inches ....3.3 cu ft , box is made with 1.5in conference table, sub is black brick audio, anyways my question is if I were to put another 4in port next to the other one, chop off the angle piece, how long would each port need to be? The correct port length for what I'm trying to get (31hz)is 7.75in with a single,so would 2 4in ports be about 4in long or 14in?
If you add a second port then both ports will need to be longer.
Is it possible to make a 1.5 cubic feet box and tune at 32 for an 8 inch sub?
Absolutely. In this video I show the formula and spreadsheet that I use to make my calculations.
ruclips.net/video/U5BQdnagzW8/видео.html
Hello, i have a Ground Zero GZCS 10SubAct and I was really disappointed by the poor bass quantity, I would like to install a funel port but I don’t know the placement or the length that would be needed.. any help from someone ?
That is a great question, join us on our next live show and we will try to give a detailed answer: bit.ly/3PYKG5P
I want to know about using 2 round ports compared to 1 bigger round port
It works the same as using two slot ports instead of one slot port. Each port only sees half of the enclosure.
@@DIYAudioGuy I'm about to do a different build and go with 1 15 in the middle of my single cab and thinking of doing 2 ports one on each side facing up. Or just use 1 on the passenger side to help with loading?
Can you lengthen port outside of the box? Is it same?
Yep, it is the same.
Can you explain horn enclosures and the benefits?
I don't know much about them.
Tapped horn is where the magic happens, but huge box size. I built one for a single 12” and it was like 8cu ft . Played down to 25Hz at 130db tho
Great video boss
Thanks!
Let's say I'm ok with the physical dimensions of the box with a longer and larger overall cross section port, at what point does air velocity become a problem on the lower end of your chart @11:33 time stamp?
Example: Manufacturer calls for a single 4" round port 11" in length for a 12" subwoofer in 2.0 cuft. I'm considering two 6.5"x1.5" slot ports 20" in length on either side of my design.
For sound quality you want to keep the port velocity below 17 m/s. You can get away with more for an SPL build (as much as 30 some say). Flared ports should let you double that number.
@@DIYAudioGuy I'm talking about the opposite end of the spectrum, where velocity is significantly below 17 m/s because the ports are huge and long.
I have two massive audio subs. spec rating on paper is not true, so I contacted massive audio and they told me 4.0 cubes and a 30 square inch port... My question is should I make an open air box with bracing or cut the specs they gave me in half for two separate chambers?
It should not make a big difference. If it were me I would go with the large single chamber just because it'll be easier to fold one port into the box instead of two, and that one port will be a little bit shorter. One thing I learned on the home theater build that I just completed is that you really can't go overboard on the bracing. I would definitely put a brace down the center from the baffle to the back wall/port wall in addition to bracing across the width of the box.
I'm also glad to hear that the manufacturer recommended a nice large port cross-section like that. After modeling and building a few enclosures I've learned that ports need to be as large as possible.
@@DIYAudioGuy hey thanks for getting back to me so fast {comma} I talked to a couple other guys and they said those are great specs I just need to design an enclosure that fits them LOL. Having some breakthroughs recently too, and that makes the next thing easier to understand so port calculating is next thank you again.
@@cocomaster3755 what tuning frequency did they tell you to shoot for?
@@DIYAudioGuy 34 HZ.
that speaker is 600rms with 1200w max. so your saying peak is 600w? and that 80% should be what you should feed it?
Always ignore the max power (maxxpoweraudio.com). I model with 80% power in WinISD because in the real world you have to deal with box rise, power factor, and low voltage. So you it is very hard to get the full RMS power out of an amp.
@@DIYAudioGuy i have the sinbosen fp14000 for my subs, i have the fi audio neo 3.5. I do appreciate your channel and feedback I like learning from the pro's
what software are u using
Sketchup
If you took a 15 inch pro audio dj subwoofer that has a frequency response range of 40 hertz to 2000 hertz and slapped it into a prefabricated 15 inch car audio subwoofer enclosure that is tuned low around 25 hertz will it still hit low and still produce deep bass.
Hard to say. It will really depend on the driver. It will definitely get loud, those PA/pro audio drivers are very efficient.
Hello , what's the app you use to design and see results of these boxes ?
ruclips.net/video/yZNeYBYGRKk/видео.html
Question: How long should my 2 8inch aero ports need to to be for my 14cft box? I'm installing 3 Resilient Sounds Team 18's subwoofers in it and i want to tune it to around 32 to 35hrz. Please help me, thanks👍
diysubwoofer.blogspot.com/2021/05/custom-subwoofer-enclosure-designs.html