Designing a 6th order Series Tuned Double Bandpass Enclosure

[@user-sk1zp5lm5x]

by far the best tutorial i have came across ever bro ur the only one that has acted as if u know what ur posting or everyone else wants views but giving no secrets GREAT JOB !!!!!!! THX

[@caraudiolab]

Thanks, I appreciate that!

[@user-sk1zp5lm5x]

@@caraudiolab some folks saying u seem pretty accurate More like dead nuts accurate and that’s from a 36 yr veteran of car audio builds But most peeps ain’t instructor s

[@caraudiolab]

@@user-sk1zp5lm5x Thanks, I immersed myself into car audio for a few years to try and understand everything. I am still learning though!

[@vivelawhiterose6459]

Hi, im currently trying to design a 6th order wall. Never done anything like this before. I just want to say a HUGE THANK YOU for this video and a few others you've posted recently. I've learned quite a bit. MUCH LOVE AND APPRECIATION!!

[@caraudiolab]

That is awesome! I am glad they help!

[@vivelawhiterose6459]

Could I ask your opinion? Currently running four sundown U15 V2 in a ported box (12cf net, tuned 35hz) in the cargo area of a 2000 Escalade. Powered by two surge 7k @ .5 ohm each. One amp per pair. Burping 154 @ 45hz sealed, clamping just over 12k. Currently designing a 6th order b-pillar. Leaning towards a 1:3 ratio (I want LOUD, rather than bandwidth) current design is: Rear 11cf net @ 30hz (12" aero port) Front 33cf net @ 50hz (30" "aero port", only a couple inches length) Most of my daily music is 30-50, that's where I'm most interested in it being nasty. Little wind would be nice around 30, but not a priority. I want my face ripped off in the high 40's area. The questions I have are; Should I go 30hz rear, 55hz front, or do you think 30hz-50hz tuning will be ok? (Unsure of cancellations as you mentioned, I'm new to this and it's a lot to learn) Current design has my subs in a wall (not flat mounted) with 12" aero port in the center, which is directly behind and directly in line with the front port. Would this be better/worse than say four 6" ports, one in each corner? (Four 6" I believe is equal to one 12") I'm unsure which would be better placement? The 1/4 wave of both ports aligns almost perfectly with the dash with the current design.

[@vivelawhiterose6459]

Any info/suggestions you can give (I know every setup varies, and testing/tweaking usually prevails) would be much appreciated. Just trying to learn as much and get as close to what I'm after building the first time, lol. Thanks in advance! Keep up the awesome content!!

[@caraudiolab]

@@vivelawhiterose6459 Design your bottom/rear/lows chamber first. Then, give the rest of the available room for your top/front chamber. Run your design by that Facebook group for additional recommendations/tips. Some of those guys may have run your exact subs in setups and may have good advice. Good luck!

[@caraudiolab]

@@vivelawhiterose6459 Great rear chamber size, you may consider upping your front chamber some for those nasty highs. I would tune 28/56. If you tune to 28, it won't really pick up till 30 hertz and be loudest from there through about 60 hertz. The 4 ports may help even the loading out. The single 12" port will be most efficient.

[@ntlaflaredewayne9863]

I've been building 6th orders the old school way of building it and listening to see which frequencys are louder but this is the first I've heard of quarter wave on a 6th order..good info everything I've built from small motors to huge xmax subs. 7 sq in of port area on the rear almost always works as far as the front it depends on it being a trunk box or blow thru or SUV it ranges from 15 to 25 depending on xmax ......good info .

[@caraudiolab]

Thanks for the feedback!

[@waltlivernois6241]

Thanks again for information

[@Husky_Shane_BassHead]

yes, please do a negative ratio box

[@caraudiolab]

Added to my video list, thanks!

[@dylantoney3322]

Bro I love what you’re doing helping me out a lot no one talks about series 6th orders

[@caraudiolab]

That is why I made the video! No info out there! Glad I could help!

[@Husky_Shane_BassHead]

man, I really like your channel. I feel like you are answering many questions that Ive had over the years, and several that I have currently

[@caraudiolab]

I appreciate it! I feel like I am just answering all the questions that I had when I started my journey! Also, I try to focus more on the technical theory that no one really like to get into for some reason.

[@Husky_Shane_BassHead]

@@caraudiolab yeah, it’s really hard to find reliable and consistent Info online about any of this stuff. I like having someone explain why something works the way it does. Love the channel.

[@caraudiolab]

@@Husky_Shane_BassHead Be sure to give me some questions that I can use for video ideas too. ;)

[@mrlmsf]

Great video! A little more difficult for me because I'm using KZbin's simultaneous translation into Portuguese. But I've already cleared most of my doubts. Thanks!

[@caraudiolab]

That's great!

[@brendangardner7639]

Love it I can say that what you said lines up with what I have learned myself

[@caraudiolab]

That is awesome!

[@keithladd-yx7bg]

Thank you for what your doing. Love the channel

[@caraudiolab]

So glad you enjoy the channel! I only keep going because people let me know that I am helping them. I appreciate your feedback so much! If you have content you want me to cover, let me know and I will add it to my video ideas list. :)

[@jasongrant3202]

This video is excellent! Great explanations!

[@caraudiolab]

Thank you!

[@dylantoney3322]

I feel so much more confident in my knowledge now 😄

[@caraudiolab]

That is awesome! I am glad I could help! There is so much to understand with this type of build!

[@Paxozpz]

Love the channel brother, could you do a video on 4th orders? Also interested in enclosures in outdoor environments and the science behind it. Just an apprentice here tryna learn more audio. Thanks

[@caraudiolab]

Sure! I have added the topics to my list. I think I might have an expert that I can interview for the science behind outdoor enclosures. You specifically want to know about subs in outdoor or mids and highs as well?

[@abelscaliber7969]

Outdoor bass is 99% some form of a horn enclosure. Since it does NOT need walls of a car or environment to load off of. The wave has already been acoustically amplified by the horns throat.

[@caraudiolab]

@@abelscaliber7969 Great feedback, I was already thinking something along those lines. My mind immediately went to turbo box. Although, you could use a corner outside for some loading or use a big box that incorporates loading. Although, that isn't very efficient.

[@Paxozpz]

@@caraudiolab I have definitely been tempted to build a horn enclosure, but don’t know enough technical to properly build it. I make boxes for ATV vehicles and SXS which typically have no enclosed cabin. I have tried multiple regular ported enclosures and 4th orders. Still working on getting my numbers and ratios right and learning everything the correct way

[@caraudiolab]

@@Paxozpz Awesome, that gives me something to work with!

[@KianF]

just an FYI, VituixCAD can model series tuned 6th’s in the Enclosure Design section. it’s called a “bandpass type 2” in the software. it’s definitely easier to use than Hornresp and there are a lot more filter/EQ options to simulate cabin gain and stuff.

[@caraudiolab]

Love it, thank you!

[@johnnysix7162]

thanks so much for putting this information out, i've been kinda comparing this with information i'm finding via 6th order build logs and it seems to be pretty accurate... it's helped me a lot... gonna be building my first 6th starting this weekend so trying to get as much knowledge as possible.

[@caraudiolab]

Glad it was helpful!

[@NateHarrisCreations]

You can do a negative port, all that is the port extends above the baffle.

[@poopandfartjokes]

I hope you’re joking

[@blakebrockhaus347]

People are absolutely choking off their builds when they do super small rear ports imo. It will net you more ultra lows, since it acts more like a leaky 4th than anything else. But that comes at the cost of any real boost to the lows in the main tuning range

[@caraudiolab]

I completely agree! The trend is to make the bottom/back chamber port smaller at the same time that subwoofers are gaining excursion! They are totally chocking their lows!

[@blakebrockhaus347]

Tbh I think the rise in high excursion subs may be part of why some guys do it. They've been told that a 6th is better for lows so that's what they build. But high excursion low motorforce subs make up most of the budget market, and those do best in 4ths. This is what I found with super small ports in my build. I tried out a single 4" aeroport for 2 12s and it behaved more like a sealed box until I ran into chuffing. But even then, the fact that I was choking off output helped because I could play all the way down to the single digits without completely unloading.

[@caraudiolab]

@@blakebrockhaus347 I haven't necessarily thought of it that way, thank you for the new perspective! I am going to have to look at it from a new angle and rethink on it. Thanks!

[@dylanhall1588]

So ive always heard that adjusting the rear chamber tuning frequency will change the front chamber tuning frequency and vice versa. How would one predict this to reach a plan to build a baseline (prior to fine tuning through testing)? Or just use a generic port length calculator to find innitial port length for each chamber assuming the are not correlated?

[@Randy_G]

Super awesome video. Please do the negative and what about an isobaric 6th order? Showing my age there. :)

[@caraudiolab]

I would like to talk to someone running high excursion subs in an isobaric 6th orders before doing a video on it. I know the traditional technical side but wonder if running a half sized box with half sized ports would work well with newer high excursion subs.... Interesting idea! I have added the negative ratio to my video list. Thanks Randy!

[@user-sw5fe3rf9s]

great info

[@caraudiolab]

Glad you enjoyed it!

[@nicholasram8235]

Brotjer now uk u gotta help out on 4th orders.. specifically hkw to get windy with a single or double 10/12" 500wRMS subs in a trunk

[@caraudiolab]

I have a video planned on 4th orders and one planned for how to get windy. Keep a look out, not sure when I will get those done, I am still putting together stuff for them!

[@nicholasram8235]

@@caraudiolab gaawwwtt daamnnn i fkin love you man, no homo... you and probably 2 other person described a 6th order sooooo good for me eh.. i love it, thamk you soooooo much❤️🙏

[@cristovalmontoya5222]

Wish you could go more in depth about port area in rear low and from high. Like some say 4.5 to 6.5 or port area per cube in rear and 4 to 5 times that in front higher tuned port. Can you do a revision and get into port area?

[@caraudiolab]

I plan on doing a video where I design a series 6th order, I can go into more depth on the port sizes in that video.

[@caraudiolab]

Also, most people go with 3 to 4x the size in the front as what you use in the rear, but they still test and adjust after making the box.

[@guhhran8614]

The reason why the Front port should be way Bigger is cuz the high er frequencies needs to be way louder in the car cuz they dont get as much cabin gain as the low Notes so you Design the 6th order to Boost the higher Notes more than the lower Notes which needs a way Bigger port. For Series tuned 6th order the lows also needs to go through the high Port so it must be even Bigger. Someone told me He would always Start with designung the low chamber like a normal ported Box, then Start to adjust the high chamber to the tuning and volume it needs, simulate which port size it needs in both chambers to dont chuffing and after that He adds the port area of the low port to the are of the high Port area and this is the final high Port area. Thats why i build a parallel tuned no wall 6th order, way smaller high chamber an smaller Port resulting in a smaller Overall Box. If i want to put in even more woofers in i would need to build a Series tuned since it gaves me more space for woofers but then it would be a wall build ​@@caraudiolab

[@rasmusnrlev9094]

How do I determine port length? Am i just missing something? 😅

[@caraudiolab]

I will create a walk-through example that will help clarify. But, you figure out the port length using a port calculator, just like you would with a ported box. The rear chamber size determines the rear chamber port and the front size determines the front port.

[@johny-xy7iu]

What software are you using?

[@waltlivernois6241]

Keep the Rockford in same box just add 4 more skar vxf in different box with 4 more amps

[@idanoknin8241]

Can you male a 1.5/1 box guideline

[@anubisprince36]

What about Port compression in the rear chamber because of the small port area?

[@caraudiolab]

Consider you start with a big sized port, you should get pretty loud on the lows. As you shrink it, you will start to loose spl in the lows but gain wind. AS you continue to shrink it even more, you will still continue to loose lows and stop gaining wind but will hit port compression. Honestly, once you start to loose spl from shrinking, you already hit some port compression, that is why you start getting windier. Once you shrink the port to much, it acts like a 4th order that has a leaky box.

[@anubisprince36]

@@caraudiolab Starting with 10-14 SQ inches per cube is where I'd like to start. I treat the smaller chamber as a normal ported box.

[@Alanreaks35]

Is there a place where i can DM you to discuss 6ths further? thanks in advance

[@caraudiolab]

I just created a CarAudio Lab facebook account today, you can friend me. Additionally, you can email me at [e-mail]

[@waltlivernois6241]

I have 4 Rockford 12p3 and 3000 watts mono amp very very punchy at 35 to 45 hrts so I have room so I want to add the skar vxf 12s 4 more I know that they play 20 to 36 very loud and low hope that they will play all hrts with authority

[@caraudiolab]

You mixing the skar with the Rockford subs?

[@dqmnjohn_4491]

hi i wonder if you could explain how to get loud bass outside the vehicle

[@caraudiolab]

Interesting idea, I just posted a video on it for you. Cheers!

[@waltlivernois6241]

I don't do this for a living in just a machanical contractor

[@anubisprince36]

How much 9f the rear port do I extend into the top chamber?

[@caraudiolab]

I have seen it done lots of different ways, every build may like something a little different. A good start it half in the top and half in the bottom. Then if possible, you can adjust it with testing in the future.

[@olekristianrannekleiv762]

6 min into the video, 30-70 is not a large gap in tuning and abit missleading. In PA application the tuning can be much futher apart. Nexo stm118 for example is tuned 36hz, 100-120hz somewhere, it is their top of the line touring grade subwoofer. I mean no offense to you video, just a small correction.

[@caraudiolab]

Appreciate the feedback, I am not as familiar with PA applications.

[@jonathanwall2814]

I guess it depends in your desired frequency range. In car audio most people aren't going to be interested in anything over 60hz, maybe 65hz for a demo/spl build.

[@caraudiolab]

@@jonathanwall2814 very true, which is why I would never consider tuning as high as 79 hertz. thanks for the support!

[@tommykammers5246]

You can't draw any better then you can fake like you know what your talking about. It's ppl like you got us out here. wasting hundreds of dollars on wood. Go talk about something you know about and leave the rest to ppl that actually know what they are talking abut ⁹

[@Chris-B-Bassin]

Well please show us the correct way

[@XXXCRSPL]

Dickhead much?