New Built sub enclosure not sounding right......

[abbss1]

Um...

Interesting... They probably had some serious power input...

I tried it and wasn't happy with it... maybe 2 would sound great!

 

[thejessman]

Hi Brian

Yes it does have a pole vent so I may move around with dimensions a little...

And I've tried it in a sealed box a little larger than recommended and it sounded s+++...

Could you tell us how large the pole vent is (rough diameter)?

I'm going to disagree with Brian and say you probably don't need a full 1.5" between the motor and the back of the box, but it does depend on how large the vent is.

 

[abbss1]

I think top of my head around 1.5" give or take .25... not sure but I'll check later and let you know mate...

Also checking the enclosure you recommended, it works out to 1.8 approx. After 0.29 sub displacement....

 

[thejessman]

I think top of my head around 1.5" give or take .25... not sure but I'll check later and let you know mate...

Also checking the enclosure you recommended, it works out to 1.8 approx. After 0.29 sub displacement....

Yup, you are right, my bad for not double checking my work. Ill fix it here in a bit.

 

[abbss1]

Sorry for the trouble again mate ...
Really appreciated...
Thanks

 

[abbss1]

So do you think the problem with the enclosure I built was due to the port area being too small????

Losing the output at lower freq....

 

[abbss1]

CONFUSED!!!!!!!
Really...

 

[thejessman]

Do you have any pictures of your current box? Do you have a picture of it in the vehicle?

 

[abbss1]

I've posted a pic earlier in this thread don't have pics of it in the car but can do tomorrow

 

[abbss1]

That's one of the pics mate with the top off for. ....

 

[thejessman]

Ok, so here is the proper design with 2.0 cu ft of net volume. I just made it .75 deeper and adjusted the port length accordingly. This should also alleviate any potential concerns about the pole vent having enough room to breathe.

 

[thejessman]

So do you think the problem with the enclosure I built was due to the port area being too small????

Losing the output at lower freq....

I think your port was too small for the size of box you had, and your net volume was too big. There could be other explanations for why your low frequency output suffered as well, but those two things jumped out at me.

 

[abbss1]

Hi mate...

Just checking out the box you designed...

I think you calculated the port as 12.5x3...
It suppose to be 12.5x3.5 to get 43.75 port area...
This is making the length around 50 inches...

Can you just confirm this please...
Cheers

 

[thejessman]

Hi mate...

Just checking out the box you designed...

I think you calculated the port as 12.5x3...
It suppose to be 12.5x3.5 to get 43.75 port area...
This is making the length around 50 inches...

Can you just confirm this please...
Cheers

Nope, I calculated it as 12.5 x 3.5".

If you are using WinISD, its going to give you a wrong number for port length because it doesn't properly compensate for end correction with 3 common wall slot ports, like what is in the design I gave you. What happens is the port interacts with the sides of the box and it performs like it is longer than it actually is. If you use the length WinISD gives you it will tune you lower than you intend.

The design I posted should be tuned to about 32 - 33 Hz. Tuning calculations aren't an exact science.

 

[abbss1]

Cheers thejessman...

So here's my plan...

The box I already have I will add a extra piece of mdf inside it so it's 2 cuft net...

As the port opening is 12.5x3.5 already just need to extend it...

Can you give me the length of the port please...

Cheers

 

[thejessman]

Sure, the port is 44" long, which is about as long as you can get away with before running into pipe resonance issues.

Make sure whatever you do you get good airtight joints. The slightest leak at all will destroy performance.

 

[abbss1]

Hi all...

Been really busy last few weeks... Family commitments...

I've modified the same box to 2 cuft and I've extended the port to 45 inches rather than 44 inches as I miscalculated the length some how.. my bad...
It's all definitely air tight...

Thanks to all for your comments and suggestions...

BIG BIG thanks to 'thejessman' ....

The Orion has come alive and it really really pounds almost everything...

Bass around 40hz-55hz is pretty impressive which I thought would be lost due to lower tuning and below 40 I'd guess early 30s the Orion is a BEAST... its really slamming the those lows now...

In a few weeks I'll hopefully be building a new box for it...
May need help lol...

Trying to post some pics of it but it's not allowing it...