Build a proper subwoofer box - Makes a BIG Difference

[@91CavGT5]

A few years ago I decided to try my hand at the $150 car audio SPL challenge…. just for fun. I bought four PAC8 8” woofers from PartsExpress for just $8 each and powered by a cheap $99 500 watt subwoofer amp from Walmart. I designed a custom 4th order bandpass box, built it, and then put it into my 2018 KIA Niro. Once it was all wired up I was shocked at the volume and the overall sound quality. After taking it to a local car audio shop to get SPL readings, it hit 135 db at 47 hz! I was VERY surprised, and so was the car audio shop too. I made a series of videos on this on my channel called “Budget Boomin”.

[@Elnufo]

Everybody likes a cheap build, well done sir! 😊

[@El_Diablo26]

I built my first double 12inch box last week, I wanted to put an 8 inch aero port but the one that I wanted to buy was actually more expensive than all my material put together so I bought an 8 inch pvc pipe which worked out to 80% cheaper. Next step was flaring the pipe which was done easily using a gas stove. Box specs: H - 350mm W - 920mm D - 380mm Took it an SPL car show today and did a 147.4 db's @ 55hz

[@georgem6359]

I enjoy every video you make. They're quite instructive.

[@evilinside5984]

@AudioJudgement- I was waiting for the max SPL#s. It would be interesting to see how the Db would vary testing forwards in the trunk/boot, seat up, then seat down/ski hole. Then enclosure facing up, then backwards, seat up, seat down/ski hole. Testing @ 25 watts, then 100, then 200 watts, for all tests.

[@scottw1938]

The predicted frequency response graph from the modeling software looked like a 6th order, not a 4th. The bandwidth was also what I would expect to see from a 6th order...very interesting. I've never been able to get my 4th order enclosure designs to ever model out like that. On a side note, thanks for making some of the absolute best videos about speakers, home and car audio, enclosures, etc, on all of KZbin. Very informative and entertaining! Please keep up the great work, Marius. (Sorry if i misspelled your name.😇)

[@Pentenfi]

I guess it's because this is a high q driver. The sealed enclosure is still way to small so this causes the first bump

[@CletusDB]

Love the channel man. Would love to see a similar video with a shallow mount sub, what's the best box etc

[@Pentenfi]

I love this approach, great stuff. I recently bought a sph-250tc used for 30Euro and followed a similar "building a no compromise enclosure" approach. Fun stuff

[@Luke-qs2cg]

A 30hz capable sub that can happily operate in a hatch at 20-25w? Sounds perfect lol

[@robertdenaro3514]

I would put 4 in a sealed box wired in parallel with a 400 watt class D amplifier

[@adammarsden2643]

I did just that Abt 4 years ago.6 cuft total sealed it worked very very well for home theater

[@Grommet2007]

Fb is lower probably because your model didn't take into consideration the damping added to the sealed chamber. For 4th order BP builds, I like to get the sealed chamber right first (using DATs, measure Fb with the driver access panel off, add or remove stuffing until you hit the target Fb for the sim. If you used something like WinISD for the sim, you may find that you actually have to tune a bit higher than Fb to get a level passband, because WinISD doesn't take into consideration factors that impact the woofer's response at higher bass frequencies, like semi-inductance. Finally, if you go with a much larger vent, or more vents, you may find that you have to trim them much shorter than expected to hit a target Fb. The classic equation for determining vent length for a given Fb starts to get more inaccurate at the volume of the vent starts to exceed more than than 10% or so of the volume of the chamber it's in. Something I discovered with my "Enigma" 4th order BP build. BTW, love the idea of using silicone to seal the last panel...!

[@brianmack6285]

How much does the car interior volume (cu ft), being smaller than a typical room, affect the measured tuning ?

[@Grommet2007]

@@brianmack6285 Probably very little, unless the vent was placed pretty close to a nearby panel or surface in the car.

[@scottw1938]

Thanks for this info, 10% is nothing. Usually, I find slot ports will make up 20% (or way more) of the volume of the enclosure, especially with high excursion subwoofers. This might help explain why I have found that I usually needed to aim for an Fb of 30Hz when I really want an Fb of 32Hz.

[@Grommet2007]

@@scottw1938 When the volume of the vent is 10% or more than the volume of the box, the actual Fb achieved starts to be dependent on the geometry of the box and vent and where the vent's entrance is located in the box. For the typical slot-loaded car audio subwoofer, I found it better to model it as an offset-driver / offset-vent stepped transmission line (3 steps). On my website, I've got a workbook called BOXPLAN-VBSLOT that allows the user to enter the dimensions of the box and the slot, and the workbook generates the corresponding sim file for use in Hornresp. For my "Enigma" 4th order BP build, I used 2 long 3" flared vents for the vented section, and I had to trim about 20% off their length to achieve anywhere near the target response curve. Yes, I had to make the vents shorter :-).

[@Clint3571]

The JBL CX 1200 is impossible to beat at the $40 Black Friday price.

[@FishingWithJo415]

i have 2 that i bought on black friday and i just installed them in a sealed box and im blown away how good they sound. They sound way better than the skar VD 12s. people shouldnt underestimate buying REAL brand speakers compared to these cheap made brands, especially how these real legit brands dont need a crazy amount of power to them

[@Ultronage]

bro can you tell us how can we desigen and build proper competable box for subwoofer and with other any driver plz

[@stachu4587]

Make new diy audiophile speaker build! And compare to previous one. Im sure you gain some more knowledge so will be interesting to see and hear what would you change today after 3 years from last build.

[@andreymosin1884]

Finally new video!

[@FishingWithJo415]

people remember if your going to run your stock alternator and cheap electrical amp kits please dont buy crazy RMS subs, Your just going to create more expenses and your not going to give your system full potential

[@maesl69]

Hey, I would like to build this sub. I have a question tho: I heard the HE version of the 12SW-4 is better in basically every aspect. But is the HE version even compatible with that enclosure? If not, what should I change?

[@stephanladurner397]

Great video! However the test tone seems to clip the mic input (or the youtube compression algorythm).

[@LatvianVideo]

Probably the mic, mics can usually be clipped quite easily

[@drrckhamilton]

Always enjoy your tutorials. Just curious a to what program that you use to model the subwoofer box.

[@rbmarius]

Win Isd

[@chichidouglas5078]

I use wood glue and there's an easy way to take the back off without ruining the box or the panel. I just put a demo blade on my circular saw and set the blade to 3/4" and cut it out.

[@VillemVallimaa]

Next try the HE-version 😎

[@vicentecortez8636]

Nice!!

[@wahidtrafo6009]

permission from Indonesia to come back to study

[@drrckhamilton]

Still waiting for your "expert tutorial" to show us how is should be done 😂.

[@catalin94doru]

Salut. Ce freza folosesti si totodata de unde ai achizitionat "ghidajul" pentru taierea cercului 😅?

[@AudioJudgement]

jaspertools.com/collections/professional-grade-circle-guides/products/jasper-240-pro-ltd-ed-cuts-perfect-circles-from-1-to-18-3-16-d Freza e DeWalt DW621-QS. Sablonul e compatibil cu multe freze dar majoritatea sunt model american. Teoretic e compatibil cu orice freza daca gauresti sablonul unde trebuie

[@catalin94doru]

@@AudioJudgement multumesc de raspuns. Vad ca nu livreaza in europa😅 deci mai caut.

[@AudioJudgement]

Incearca pe amazon.com sau pe aliexpress cred ca gasesti niste chestii asemanatoare daca cauti router circle jig

[@rbmarius]

​@catalin94doru Au avut la Lidl, Parkside, găsești și pe OLX undeva la 200 ron

[@catalin94doru]

@@rbmarius da am de la bosch si parkside dinacea mai mica , ma interesa ghidajul defapt 😅

[@staLkerhu]

4:04 Oooff............ 😵‍💫

[@BaddDukk]

What, ooof? I would have used a foam gasket but nothing wrong with what he did. 🙄

[@staLkerhu]

@@BaddDukk if you did not see that terrible crack, then you really need a VERY good eye specialist!

[@fredy000]

very good english dar mereu imi dau seama ca esti roman dupa accent :)

[@modifierle]

Trash it with the full force of 100 watts!

[@LatvianVideo]

The box truly is everything, I made a 6th order using a logitech z623, didnt lose that much output, but it goes WAY lower In a wagon, the freq response was about 27-52hz, the listed 2 frequencies are -3db from the peak output, but it was measured using my phone, so it has to be taken with a grain of salt

[@staLkerhu]

Used what order?! 🤨 Jesus F............

[@LatvianVideo]

@@staLkerhu 6th order, isnt that complex, is just like the 4th order, just both sides are ported

[@Herman-f9m]

Qtc=1.6? No wonder car subwoofers sound terrible. I've never actually heard a good one, but then, I never went looking. I only get to hear the complete rubbish ones driving around my neighborhood waking everybody up at 2am. They're really lucky nobody takes a shot at them.

[@arnicus208]

You’re not building a subwoofer, you’re building a subwoofer system. Don’t understand why people say the are speaker builders when the build enclosures.

[@frankd.b.9233]

db is not what you need to have good bass but low frequencies and big ohms