Hello guys

Can you help to design a box for my subs, here is the info about what I want

Subs : 2 (ssa xcon dual 2) 10 inches( 2017 model). Here is the ts parameters

·         FS: 37.9

·         QES: .38

·         QMS: 5.3

·         QTS: .35 

·         SD: 310

·         VAS: 8.4L

·         SPL: 82.7

·         BL: 15.74/22.25

·         RE: .7 ohm / 1.4 ohm 

·         MMS: 279

·         Xmax: 29mm

·         RMS: 2000W

 

Sub amp : 2 zapco st-2000xmii strapped at 2 ohm

Car : yaris 2010 sedan

Box location : in the trunk with sub and port pointed toward the cabin because I wanna sealed the box off

Space available : I will have a weird shaped box because I have to have access to batteries the net available space inside the box is 5.8 cube.

Rear seat: I have 3 rear seats. I can fold one seat behind the driver seat or I can fold the middle and the one behind the passenger together because they are attached and of course I can fold them all  

Electrical : 1 singer alt 320 amp with 3 acid batt of 250 amp combined

Bandwidth needed : from 25hz to 50 Hz minimum. The wider the better especially on the lower side but if it will comes at the cost of achieving the goals over the needed bandwidth then I don’t want it

Goal : daily system with clear clean accurate sounding bass, extremely loud across the bandwidth while murdering the hell out of the lows especially 32 hz and below

Type of music : I listen to every type of music. Rock, jazz, pop you name it and I listen to a lot of slowed music . decaf djsnt and such

Proposed box : based on ssa recommendation and my little knowledge and the space available I thought  3.5 cube tuned to 31 with 60 inch squared of port area or 3.5 cube tuned to 28 with 52 inch squared.

I have graphed the tow boxes in Bassbox6 pro. The yellow graph is 32hz box, the orange is 28hz. here is the result

https://imgur.com/a/qMMou

This is the typical response and as you can see the 28hz box have an advantage over the other box from 30hz and below which is really what I want.

But

Here is the response when I apply the port resonance

https://imgur.com/CETIEWv

As you can see the 31hzbox is louder from around 27hz and up over the other box . which if it was true I will do it

My questions : is my tow proposed designs are going to help me achieve my goals and if so which one of them

Is the port resonance predicted by the program true

Where should I place the port ( behind driver seat or passenger seat or in the middle ) the port is slot

If my proposed designs are wrong what is your recommendation based on everything I mentioned

Any help is appreciated and if there is anything you want me to add please tell me

I hope I covered everything needed and thanks in advance    

  

 

  

Welcome to SSA

Thank you Randal

Welcome. You’ll love the subs 

Thanks ManzKea

Welcome to the forum.

I hope you'll find some good help for that box. 

 

You'll love those Icons !

Thanks guys 

@///M5 i would like to know your input 

What you want and what makes sense aren't two things I put together...but I have zero music that has lfe like you are desiring.  

@///M5 i didn't understand your reply can you elaborate. And which design do you think will help me achieve my goal and if you have any suggestions iam all ears 

Edited January 5, 20187 yr by Abo raya 111

I was saying your goal doesn't resonate with me.  And as for how your car will respond, that no one can predict.

So if it was your equipment iam interested in knowing your goals and what design you will do

I ONLY care about musical reproduction.  The lowest note on an upright bass is 41Hz and while yes a piano can play 27.5Hz it is really rare and not that important to me.  I would then setup my system to be able to deal with that.

 

I see. So what do you tune your boxes usually

Welcome to SSA!

Both designs look good for your desired goals. I personally would do the box tuned to 32hz with a little more port area. Either one will crush your throat and blur your vision, but the one will be a little more efficient. (make better use of the power)  Even tuned to 32hz, 28hz will be plenty loud.

  As far as port placement, you will not hear a difference by ear, so do what is most forgiving from the design side of things. 

I always love the sound of a sub firing into the cabin, sealed from the trunk. Good lucky with the build eh!! Don't for get to take pics and post a build log!!

Thanks man i really appreciate it 

I know the 32 will be more efficient but what about the 20s.ike that area very much do you think the 28hz will have more advantages in that area or not really at least down to 26hz

Thanks in advance i will upload pics as soon as I do it

I forgot, how much port area do you think is best if i go with 32hz and what is the benfit of a bigger port

Thanks in advance 

If you are obsessed with teh lower tuned box, then that is clearly the correct choice for you. 

Personally I think you are hung up on the math side of things and forgetting you are going to be playing music.... music is dynamic, not linear like the graph you are looking at. If a song has a 26hz sound, it will make that sound weather the box is tuned to 32 or 28.

At the volume levels I can already guess you plan on, 26hz will be there either way and the slight gain will be felt more than heard. Everything above will have lower output. IMO thats a shitty trade-off in a car. I would take the 3db gain from 30hz up knowing the 6db down at 26hz will still be shaking the hell out things. 

Port area is based more on the power planned, than the enclosure volume. If you plan on listening at full tilt most of the time the larger the port the better... because it will have less port resonance.

 

 

Yes you are right iam kinda obsessed. but you make a great point tho, if the difference is minimal then 32 hertz its

Thanks for your help man

@j-roadtatts i did a little calculation, i can tune it to 32.5 hertz with around 69 in^2

What do you think

5 minutes ago, Abo raya 111 said:

@j-roadtatts i did a little calculation, i can tune it to 32.5 hertz with around 69 in^2

What do you think

I think that would be tits! Will move a ton of air with almost 20" sq in of port per cube, without the port coloring the music at high volume.

You are the MVP thanks for your patience with me 

 Other part I forgot to mention is cabin gain, or the frequency your car is going to naturally amplify on its own. This will change your response curve somewhat also, but is not something you can really model as every car is different. It could mean you'll gain back the low-end. Or possibly gain some higher frequency, leveling out the response. Either way you're going to have loud head knocking bass!

 

 

 When you get tired of just being loud and low as possible, you can always smooth things out a little with the EQ, level the output with the frontstage and make it more acoustical.  Or depending on how easily you can get to your adjustments,  possibly have two different settings.  One for all out and the other for easy listening.

1 minute ago, Abo raya 111 said:

You are the MVP thanks for your patience with me 

 No worries. I'm not someone that has a single listening preference so can relate.