Your car's resonant freq?

[tommyk90 5,000+ posts]

Resonant Frequency Is Actually A Complicated Thing To Find Out In Vehicals,because Every Vehical Is Different Acoustically,but 1 Way Is To Take A Single Sub In A Sealed Box And Put In Ur Vehical And Meter It Playing A Sweep,then U Want To Try And Tune Ur Ported Box As Close As Possible To Wat The Meter Said

Sorry, but that is an incomplete test.

The 2nd part of that test involves metering the box OUTSIDE the car, say, in an open area such as outside. Set the sensor a few feet away (making sure to keep this distance consistent), and play TONES (not a sweep, in either case) to find the SPL level of each tone.

Subtract the SPL number you got on the outside metering from the SPL number from inside the vehicle for each note (30 hz SPL inside minus 30 hz SPL outside). The biggest difference between the numbers is the resonant frequency of the vehicle. At least this is the way I have personally been taught.

But knowing the resonant frequency does NOT always reflect where the car will peak at. As was mentioned, the box, sub, power, body style, and other things will also affect the peak note.

 

[Flipx99 5,000+ posts]

What Are You People,english Teachers

No, I am an international finance student. Proper english is essential to clear communication. These skills, you obviously lack.

 

[mikey060 10+ year member]

What Are You People,english Teachers

What are you, illiterate?

 

[Flipx99 5,000+ posts]

Sorry, but that is an incomplete test.
The 2nd part of that test involves metering the box OUTSIDE the car, say, in an open area such as outside. Set the sensor a few feet away (making sure to keep this distance consistent), and play TONES (not a sweep, in either case) to find the SPL level of each tone.

Subtract the SPL number you got on the outside metering from the SPL number from inside the vehicle for each note (30 hz SPL inside minus 30 hz SPL outside). The biggest difference between the numbers is the resonant frequency of the vehicle. At least this is the way I have personally been taught.

Again, wouldn't that be dependant on the box, or does this concept hold for all box enclosures, types of subs, etc.

or do we go back to the same old song: test, test, and then test some more

 

[Meka 10+ year member]

Only on caraudio.com

 

[Mr. Opportunist 10+ year member]

No, I am an international finance student. Proper english is essential to clear communication. These skills, you obviously lack.

What are you, illiterate?

//content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

 

[Flipx99 5,000+ posts]

It looks as though lloyd has left. I was hoping for some insight on wall building.

 

[tommyk90 5,000+ posts]

Again, wouldn't that be dependant on the box, or does this concept hold for all box enclosures, types of subs, etc.
or do we go back to the same old song: test, test, and then test some more

Like i said, it does not necessarily reflect where the vehicle is going to peak, but it does give you a start. The key in that test is to keep everything consistent. Use the same sealed box inside and outside the vehicle, keep the meter in the same place, use the same test tone CD on the same volume for each test.

And yes, it does come down to test, test, and more testing. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[B_Campbell 10+ year member]

Typin' Like Dis Makes Me Look Smarta Did U No Dat?

 

[Flipx99 5,000+ posts]

Like i said, it does not necessarily reflect where the vehicle is going to peak, but it does give you a start. The key in that test is to keep everything consistent. Use the same sealed box inside and outside the vehicle, keep the meter in the same place, use the same test tone CD on the same volume for each test.
And yes, it does come down to test, test, and more testing. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

How would you test a wall? With an adjustable port? [i am not sure if such a device exists, but I believe you could perhaps using ducting]

 

[Mr. Opportunist 10+ year member]

How would you test a wall? With an adjustable port? [i am not sure if such a device exists, but I believe you could perhaps using ducting]

start w/ a big port and keep cutting it in incriments until you stop peaking. that wont be where your resonant frequency is but where that specific application peaks at...

 

[Flipx99 5,000+ posts]

start w/ a big port and keep cutting it in incriments until you stop peaking. that wont be where your resonant frequency is but where that specific application peaks at...

Which matters more than resonant frequency anyway. So...under your method I would start with a lower note and move up (in frequency).

 

[Mr. Opportunist 10+ year member]

Which matters more than resonant frequency anyway. So...under your method I would start with a lower note and move up (in frequency).

correct.

 

[tommyk90 5,000+ posts]

Which matters more than resonant frequency anyway. So...under your method I would start with a lower note and move up (in frequency).

Not necessarily. You can also play around with the port LENGTH as well. Since most walls don't have any port length (besides the baffle), you aren't going to see a huge difference in port tuning with the decreasing port size.

Dammit, where is loyd at. He has WAAAAAAY more experience with walls than I do.

 

[Flipx99 5,000+ posts]

correct.

Thanks,

Now I just have to convince myself a wall is practical. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif