Whats the point of knowing the peak of ur cars cabin

[J.Reed]

I think to FULLY understand resonant of EVERY vehicle you have to look at more then just wavelength. Wavelength is cool and useful tool. But I think one thing that can be happening that changes this is many factors like flex that will change the cabin shape and effecting the wave along its path. I think a HUGE factor would be the airflow over certain objects ie seats, consoles, headliners, even different materials. There are millions of variables. I guess thats why the only way to see for sure it to test, test, test.

[kirill007]

So what J Reed is trying to say, quarter wave works in some cases and can be a decent starting point if u don't have a TL to test test test.

But to actually find the peak quarter wave won't work effective, in some cases it will.

(Although J. Reed if u have only tested about 10-12 cars , you shouldn't try to apply it to all cars, only if u have done atleast 120 cars and a lot of different ones.)

You can't just rely on quarter wave to find the RF of a car since way too much variables are involved.

There is no simple way to calculate RF of a car accurate, there is a way but it's quite impossible(and time consuming) to do.

Just use the TL to find it, build a sealed box which plays "flat" and play sweep tones.(doesn't works on walls or (very)big enclosures)

To answer the title of the thread:

You can use it in your advantages in SQ or SPL.

If u tune a few hz below the RF you can get high spl gains in some cases.

You can use it in SQ too.

[J.Reed]

So what J Reed is trying to say, quarter wave works in some cases and can be a decent starting point if u don't have a TL to test test test.

Correct

But to actually find the peak quarter wave won't work effective, in some cases it will.

(Although J. Reed if u have only tested about 10-12 cars , you shouldn't try to apply it to all cars, only if u have done atleast 120 cars and a lot of different ones.)

You can't just rely on quarter wave to find the RF of a car since way too much variables are involved.

There is no simple way to calculate RF of a car accurate, there is a way but it's quite impossible(and time consuming) to do.

Just use the TL to find it, build a sealed box which plays "flat" and play sweep tones.(doesn't works on walls or (very)big enclosures)

I have used this method for quite some time (since late 90's). Granted mostly wall builds and larger suvs for SPL. Never saw a reason to do an spl vehicle any other way when doing a SPL ride. My days when I was really doing it, there were no walled, non-walled classes. Only power classes and consumer or pro lol. My philosophy was go BIG or go home then, you had to to be competitive lol. Cone area was king. I have used it numinous times in daily systems with great results. And I do not "just rely" on quarter wave alone. I always back it up on a TL. Most the time in the vehicles I have tested it is a good ball park to what works. There is NO better substitute then testing on a meter. Even with my method it only ball parks you. You still have to test to verify even when it works its only close. Then with more tuning you can and WILL see even better results. Sometimes it seems to be dead nuts but mostly just close.

I also agree there is no "simple" way to get RF for ever ride. Testing is KING, but not everyone has access to a meter. This is where using math and theory of sound can be VERY useful. I personally would like to learn more about fluid dynamics. Im sure there is more out there to help gain that has not been explored using fluid dynamics.

I like the sealed box method too, but also requires you to have a good sealed sub, enclosure combo and mic. I have used this with trunks or cars that would not work to wavelength. seemed to work, but as I said I don't do those much I can't help if I like to understand more why something happens then "it just does" lol There is something causing the change. I am the type to want to know why and how I can use it to my advantage or get ride of it to help if possible.

[TheyDontWantMusic]

where do I measure from on this?

[AMI CUSTOMS]

What size are those? Is that the box that is in your car now with speakers from your avatar?

[TheyDontWantMusic]

What size are those? Is that the box that is in your car now with speakers from your avatar?

yes, they're 10's

[AMI CUSTOMS]

What size are those? Is that the box that is in your car now with speakers from your avatar?

yes, they're 10's

How much power you have on them and what numbers you doing in that laser?

[fecupe2001]

box looks sexy, i just hope you don´t get any unloading problems, there are sub WAYYY to far from the port!!

[TheyDontWantMusic]

box looks sexy, i just hope you don´t get any unloading problems, there are sub WAYYY to far from the port!!

its not a port.

clamped at 1800watts, it does 147dB on music.

I need to fix my second amp.

[fecupe2001]

then what the hell is that?