How to Design the PERFECT Subwoofer Box in WINisd

[@HifiVega]

People might think of winisd videos as boring, but when you are trying to figure out how to use the software and design your enclosure videos like this are invaluable.

[@DIYAudioGuy]

That, and get you a big 3 kit.

[@DIYAudioGuy]

Rock solid advice. Anybody that wants to build a speaker needs to watch this video.

[@zarboaudioprojects1430]

This was very informative; thanks for making this video. I've messed with WinISD a fair bit but I always learn something, or a few somethings from each video you do on it. A good tutorial on what's important to look at when modeling a driver, and what changes we make can create other changes, and why. Mostly though, I'm in awe of how quickly you can convey information like this without it feeling rushed. That's a gift to be able to do that. An equivalent video by me would be 3 hours long. :)

[@spritual_enlightenment]

Good info for those who can understand. Bless U, guys.

[@OldfarseeingArt]

I just watched this a second time. Good stuff! There were definitely a few points that you made that I had been totally overlooking. Happy to have my knowledge updated. Thank you for this. I appreciate the work you do, it is a great resource.

[@mhnoni]

I've learned a lot from you, thank you so much for sharing your knowledge and experience.

[@5333092]

Any chance you'd do one on MLTL for the perfect midbass cabinet?

[@nomnommonsterr]

Such a nice video. I'm new to the entire speaker DIY and your videos are gold. Please keep such videos coming. And thank you so much. +1 sub.

[@shawnbrennan7075]

You mention port resonance when building a sub but, what if you're building a 2-way. Anything to consider about port resonance?

[@Toid]

That's a good question. You should always be concerned with port resonance. In a bookshelf speaker, you can deal with this in a few ways. Such as careful port placement and foam lining.

[@andrewhigdon8346]

Always.

[@jean-pierreserret301]

Loving these video's just wondering if you were to replace an old Mordaunt short 10inch sub (which i find a little boomy) what you put in its place?

[@PampostReturning]

Thank you so much 🥰💟.

[@rickdodson5252]

Great info!!!

[@Toid]

Thank you Rick

[@eng-3998]

The newer version of winisd gives more options when designing a box. Do you just use this version all the time.

[@greenbassboosts8872]

What's the newest version? I thought there's no updates since quite a while

[@Mattymew]

I'm assuming that input power is the actual output power of the amplifier minus heat/ineffiency (Class D etc.)?

[@Toid]

@@Mattymew yes. It’s whatever power you’re going to feed the subwoofer.

[@welderfixer]

Nick, such good info into design. With the addition of Atmos to my system I would like to design ceiling mounted speakers that are far better than the normal in-ceiling speakers that push the sound directly to the floor in most designs. If the speaker is directly overhead that is fine, but as the channels get closer to the screen shouldn't the drivers aim toward the people viewing the movie? I currently have a pair of small bookshelf speakers hanging from the ceiling, but I'd like better shaped boxes with bigger drivers. So, it's time to get the wood and saws out!

[@andrewhigdon8346]

The directivity of sound is frequency dependent. You’ll notice that as you get off-axis from any speaker, the super highs, the very “s”y parts, fall away first, and on down the spectrum until you are 90 degrees off, and around there and further you’ll only hear lows and then sub frequencies. Ceiling speakers are designed to be mounted in a relatively high ceiling for good audio quality. As the ceiling height drops the “localization” of the sound increase. When they are in lower ceilings it’s either a compromise, fidelity doesn’t matter, or it’s simply the case that ceiling speakers get molested less than surface mount, like a restroom in a bar. Those ceiling speakers with directable tweeters are also a compromise, and kind of a gimmick. Those bookshelf speakers would generally sound better in a listening position. But if you had vaulted ceilings facing the right way, that could work for you. Don’t use big drivers just for the sake of it. Depending on SPL and applications, even 5 or 6” drivers can handle down to 100 hz, where the subs should take over.

[@DescartesRenegade]

Can DSP make it so it doesn't matter what kind of box is used? For example, a port box with less than recommended volume or a sealed box that's too large, etc

[@Toid]

To a certain degree, but it will only affect frequency response. The issues that you’re bringing up have more to do with mechanical limitations of the driver. A DSP isn’t going to be able to overcome that. It can, however, account for it, and make sure that you don’t hit them with things like limiters. But in general, it’s best to use DSP with the recommended box size.

[@DescartesRenegade]

@@Toid so a high powered subwoofer would more easily handle the misappropriation of the box characteristics?

[@jerrykamis2011]

I have a problem with modelling the morel primo 804 in WinISD. No matter what enclosure type I choose, it will always go way over the Xmax point, which is 8mm. Can you help me design a good vented box for the sub?

[@Toid]

Why don't you post it on the Forum and see if we can help you there. I might not be able to do much this week, but I'll make sure to get on it next week. Just give us an idea of what you tried and what you're trying to accomplish and what's not working for you. www.toidsdiyaudio.com/forums

[@jerrykamis2011]

@@Toid Thanks. I will check the forum.

[@goobisoft4873]

how to make subsonic filter as u said i need roll off after 30 hz

[@Toid]

If you need like a subsonic filter that high up, typically you're going to be using something like DSP. With that you can put a high pass at whatever frequency you want.

[@JoshM7]

One thing I've noticed over time with my subwoofers (or speakers in general) is I should pay attention to BL. I used to like to model and think as long as I'm just touching xmax it's fine because that's what it is rated for. But if you're going for an extreme SQ build you might want to stay a bit further away from xmax to keep distortion lower. Normally BL is rated at 70% I think. But not everyone does this from what I've seen. And 70% BL might be something like 10% distortion but I'm not 100% sure if that's always the case. If you don't mind a bit of distortion as you start to reach full power then I wouldn't worry about it. And the distortion area you'd have to worry about would only be where the xmax is closest to the rated number. And I could be wrong about this. If I'm wrong or only half right or something. Correct me so I can learn more about this stuff.

[@Toid]

No that's absolutely right. Especially if you know the limitations of the subwoofer. Like if you have Klippel measurements. Of course there is validity in the fact the lower you go down in frequency, the harder it is to hear distortion.

[@nomnommonsterr]

What is extended bass shelf?

[@Toid]

Great question. Typically a subwoofer is designed trying to keep the bass as linear as possible. What this means, is in an anechoic chamber, the volume of a subwoofer would remain at X decibles the longest (this is called a Chebychev alignment). And then it would hit a certain frequency and start dropping. When it drop 3 decibels, that is called it's F3. Which is typically how we rate its response. But there are times where the F3 of a Chebychev alignment really don't meet the lowest frequency we are going for. For that, we use an Extended Bass Shelf. This uses a bigger box. IN this box, the frequency will start dropping from the linear x decibels sooner, but it will be a slower slope. Then we tune to box to extend either to 3db or 6db past the original x decibel linear line. By doing this, we gain additional lower frequency, but sacrifice power handling and anechoic linearity.

[@nomnommonsterr]

@@Toid this is amazing. I kind of knew what f3 was but never knew the concept of designing it -6 to get that curve.. So basically you can equalise it to get flatter response and I think by increasing gain of an amp by 3 db you'd get the best? Ooh wait the cone excursion should be looked after. This really is a rabbit hole. Thanks for the reply. You have no idea how many newbies you've helped or would help by such videos. Cheers mate 🤘

[@jtmuser2245]

“4 inch woofer won’t do that”…hexibase-“hold my beer”

[@fishrrelaxing9361]

I do not like winisd for much more then modeling port turbulence tbh.. I’ve found too many issues with its outputs when comparing multiple programs..

[@NoobaudioTx]

Beginners tip:You get less excursion with a sealed enclosure or if the enclosure has a very small port it will get very little excursion too so yeah i had to learn it the correct/wrong way lols

[@sparco317]

hexibase pete fills his room with a 4" driver...

[@Toid]

Haha, no he doesn't. But it was a cool build he did. And I am definitely a fan of those tang band woofers. They are great for nearfield listening.

[@ScramTek]

@@Toid Thank you for this comment. Too many ‘experts’ make silly performance claims just to get views. “Build your own home theatre sub enclosure using two drivers from a couple of old portable FM Radios. This sucka. will shake the foundations of your house. It meets THX standards, is powered by a TDA7429P and will fit in the palm of your hand!” Okay, I’m exaggerating. But people will say that a mini subwoofer will hit 25Hz, but fail to mention this is measured at -20dB. Love your channel. Love the content. Good level of detailed info without getting too technical for the average hobbyist. Love the Sound Advice podcast too. If I can make one request, it would be to incorporate some low-cost DIY subwoofer projects using some more adventurous designs. Such as a transmission line design, a folded horn or possibly even a Paraflex design. Would love a Paraflex sub build, which essentially incorporates a folded horn onto a quarter-wave design. They’re at the cutting-edge of sub enclosure designs and can perform ridiculously well.

[@Toid]

@@ScramTek thank you. And I completely agree. I do wanna get some of those designs out they’re not on my current list to do, but they are something I do want to do in the future. Currently, my cheapest, well performing subwoofer build, is the iso 100 that uses $100 worth of subwoofers, but you still have to get whatever amplifier you want to power it. That is an isobaric configuration. And ends up using for really expensive subwoofers, but the end result is quite impressive. Here is the link if you’re interested. toidsdiyaudio.com/forums/discussion/iso-100-build-20hz-for-under-100/

[@ScramTek]

@@Toid Thanks dude. I’ve watched the build episode for the ISO100 a couple times before. Think it’s great that you used an Isobaric configuration for the drivers. That used to be quite a popular design back in the 90s in car audio builds. Subwoofers mostly weren’t engineered to perform well in very small enclosures the way today’s subwoofers can. Plus, with a perspex window in the enclosure, being able to show off the clamshell design looked cool and clever as driver and enclosure design was more basic at that time. I watch your channel and a few other US based channels (DIY Audio Guy of course). Problem is I’m British and there’s no Parts Express outlets in the UK. There is a retailer in Europe but we now pay import taxes (after Brexit) on top of a much higher baseline retail price for everything they stock. Which is another issue, as they carry a very limited range of the full Parts Express catalogue. So, following your design builds isn’t really possible. But, they do inspire me to start doing what I’ve meant to do for a very long time. Which is to design and build enclosures for fun!!! Keep us the good work dude! Reckon there’s a shitload of people like me who really appreciate what you provide for us!

[@sc0or]

Well... How can you be so skeptical regarding PA woofers, and offer to build such ... which you call "a sub"? It's rather a jealous boomboocer. The first statement you had to pronounce should be: DON'T try to build a sub without a proper driver. "if you need 20Hz take 18" and s u. Otherwise stay in your league"