Mobile Electronics Australia > resident frequency for a 1997 mirage

Full Version: resident frequency for a 1997 mirage

Mobile Electronics Australia > Mobile Electronics Discussion > SPL and Competition Discussion

orion_rules

Feb 9 2003, 11:44 PM

it would save me heaps of time if someone could tell me what the resident frequency for a 1997 model mitsubishi mirage is. im builing a SPL car, and i really need to know. thanx for your help

bassmekanik

Feb 10 2003, 12:10 AM

all cars are normaly between 40 and 55 hz as a rule...

lancer guy

Feb 10 2003, 12:17 AM

I think the resonant frequency for a Mirage would be around 47Hz. I'd use this as a starting point. If you are building an spl car the best thing to do would be to go to your nearest car audio shop and ask them to help measure your car for it's resonant frequency. This isn't hard to do and helps take out the guesswork cause even 2 Mirages can have different resonant frequencies.

Bassaholic

Feb 10 2003, 01:47 AM

The peak frequency depends on box/sub location, the car, even the SPL and sub/amp(s) can affect it a bit..

If you are building an SPL car, you really need to do some testing..

bassmekanik - I agree that many cars are between 40-60hz but I can certainly think up of plenty exceptions of very loud cars (in all classes) that use notes that are not in this range..

Feb 10 2003, 01:53 AM

some cars peak @ ~30hz....or made to peak there

Walkinshaw

Feb 10 2003, 01:58 PM

KraSE you and your aspirations of 150dB @ 30hz in the pannie

hardon

Feb 10 2003, 03:18 PM

If you get yourself a dB meter from Jaycar or Triky Diks, run some test tones and measure the output with different frequencies without adjusting the volume. keep all system settings the same, and just change the frequency. The resonant frequency will be the highest reading on the meter. Once you've found that, try moving the enclosure around the boot area to find the highest output at that frequency. Once the highest output has been found, check if the resonant frequency has changed.

The tones don't have to be at maximum volume, just a decent level for the meter to read it. maybe 120 dB - most of the lower SPL meters around max out at about 130 dB.

So play with freq's, play with box position.

If you find it hard to justify ~$150 on a meter, keep in mind that you will refer back to it often when testing a fair bit. I'm just looking at getting one for myself soon!

Good luck, and have fun!
(that's what it's all about!)

Feb 10 2003, 03:48 PM

QUOTE

Originally posted by Walkinshaw:
KraSE you and your aspirations of 150dB @ 30hz in the pannie

150 blah

lancerman

Feb 10 2003, 04:32 PM

I find that the cheap Jaycar/DSE meters aren't sensitive enough at lower frequencies. According to my handheld meter, I peak best at 52hz. But at comps I have always found the peak to be around 46-47hz. So the cheap meters would only give you a general guideline as to resonant frequency.

Bodyjar

Feb 10 2003, 04:35 PM

And don't forget, you have to do it with a sealed box! not ported!

hardon

Feb 10 2003, 09:14 PM

I was under the impression if you use the "A" weighting setting on the meter, the frequency response is relatively flat?

Bassaholic

Feb 11 2003, 12:33 AM

QUOTE

Originally posted by hardon:
I was under the impression if you use the "A" weighting setting on the meter, the frequency response is relatively flat?

Actually it is the C weighting, but yes the frequency response on those meters (well at least the dse one..) is still relatively flat.. But yes, I agree it isn't so much the frequency response, but the level of SPL you are able to test at (that explains the difference between the dse/jaycar meter and the proper rtas)..

Anonymous

Feb 11 2003, 02:56 AM

'resident frequency'?? i think hes talking about those frequency bugs that sit in the bottom of cars!!! lol
i wouldnt have a clue about resonant frequencies but i thought i'd pull the piss anyway, considering nobody else had

Roddas77

Feb 12 2003, 12:44 PM

Using the handheld dB metre test inside my gf's mirage, the peak frequency with a sealed box was at 63Hz at half volume (so it wouldn't read off the metre)!

I'm a little bit suspect on this reading, so I'm going to go to a car audio place and test it properly when I get my new amp.

This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.