Cars Resonant Frequency.

[hawkei67]

Does anyone know the resonant frequency of a 1999 Ford Taurus 4-door sedan? If not then how would I go about finding the resonant frequency? After I find the resonant frequency of the car then should I tune the box to the same resonant frequency of the car?

I listen to a lot of Gucci Mane, Plies, Young Money, ect... I have been told that you can take a bass test cd, like Decafs Collection, THX, BassCube, ect... and play the individual frequency tests and which ever test frequency sounds the best (hardest hit with exceptional vibration) then that is the frequency to tune your box to. Is this correct? I am aiming at the most SPL I can get out of an old el-cheapo Polk Audio 10" db104 sub (which I know I won't get much outta this cheap old sub). I will be kicking it with an old school Pioneer 220 watt amplifier. I have also read that you should just tune your box to 33Hz and be done with it but I am also getting confused because I see others that are aiming at SPL designing their box's at 45Hz to 60Hz, this is confusing to me. The db104 Polk Audio 10" sub has an Fs of 26.7Hz, should I tune to that frequency instead or just tune to a frequency that my car hits hardest with using the bass test cd's? I have a space requirement of 14" Height, 38" Wide, and 28" in depth that I can work with to fit into the trunk of the car. I have designed one through BassBox Pro as a single tuned bandpass with A=14, B=28, C=38, D=38, E=14 and tinkering with the volumes of each chamber to equal to 3.4cu. ft. for each chamber so the baffle and sub will be dead center of the box and use 2 vents flush on both ends with a diameter of 3" and a length of 3.376" and enable the 12dB Octave to 50Hz. I came up with 11.9dB at 39.50Hz Normalized Amplitude Response and 122.2dB at the same frequency Custom Amplitude Response. Does this sound like a good design for a single cheapo 10" Polk Audio db104?

Could someone please enlighten me on the above mentioned questions?

[stefanhinote]

Your not competing, don't bother finding vehicle resonant frequency.

Tuning to 26hz would likely be louder in the lower range (in a range that most music doesn't drop into) and you'd lose output on the higher end (that most music is in fact in...).

33hz is an average middle of the road tune.

Some people tune lower (28hz or so) but for me that's sorta a waste for what I listen to...

[blownengine]

That ^^. It really doesnt matter if its just a daily driver. Only SPL competators really use that.

Daily boxes are tuned anywhere form 30-35 hertz. I would tune closer to 34 with your sub.

[hawkei67]

Well I just went out in my car that has the crappy 8's in it and listened to the Tojo Bass Collection and did the tracks that had a 10Hz then another track that had a 20Hz, ect... up to about 150Hz and had my volume turned down to about 2 dots (wide open is 10 dots), amplifier turned 3/4 up and windows up, sub's in a sealed box 9"H X 30"W X 9"D pushed right up against the frame of the back seat with the subs facing the trunk and had the split backseat folded down and 60Hz made a hell of a sound, the side mirrors you could not see out of and the rear view mirror vibrated tremendously to the point of my necklace hanging off it boucing up and down pretty heavy and it sounded amazing. The box was a prefabbed box that came with them old crappy roadmaster 8's in it with a divider seperating each speakers chamber and it used to have 2 - 6" X 3" tweeters one on each end of the box which I removed them and sealed the empty holes up with wood I had laying around and and replaced the subs with the old radio shack csw-8000 8" subs, hooked them up to the old pioneer 220watt amp just like I mentioned above. A lil history...

Since everything pounded like that at 60Hz then should I design the box to 60Hz also?

[Robert8252]

Is the box in the trunk or getting sealed off? If in the trunk tune to 35-6. If sealed forward tune to 36-38.

[hawkei67]

The box is back up against the back of the back seat frame under the deck (when I lift up my back seats then I don't see the box) and the subs themselves are facing toward the back of the trunk lid, where the trunk latch is at. There is about a 5" gap between the top of the box and bottom of the rear deck where the 5x7's are installed and about 4" in between the side of the box and the fenderwell on each side and yes it is sealed now but it formally had 2 long rectangular tweets on each end on the same side as the front of the subs but I removed those and sealed those holes off with some old wood I had laying around so yes it is sealed and I also replaced the old Road Master 8's with the 2 CSW-8000's 8's. Thanx for info and I will try those out and see what comes up, Thank you all for being so polite with your responses and for understanding that they themselves were newbies at one time.

[hawkei67]

Should I stick with these Radio Shack 8" CSW-8000's (100 watts each) or do any of you think I should go with that old Polk Audio db104 10" sub (300 watts) in a vented or bandpass to achieve some awesome thump with the best possible spl or do you think the 8's are doing me better than the single 10" could in my particular car?

[tlee2]

Don't tune it to 60hz that's WAY too high for daily

[kr15]

if you dont compete, then tune to a freq that is compatible with the FS of your sub..its basically that simple...some VERY vague generalizations; lower tuning can usually create a flatter response curve, while tuning higher can generate more output over a short bandwith, but overall slope will be sharp

[shogen]

if you dont compete, then tune to a freq that is compatible with the FS of your sub..its basically that simple...some VERY vague generalizations; lower tuning can usually create a flatter response curve, while tuning higher can generate more output over a short bandwith, but overall slope will be sharp

^^^this...