Proper Tuning Freq- Ported Enclosure

ratchetdu
ratchetdu Posts: 3
edited January 2011 in Custom Fabrication
Hello,

New here and tried searching, but didn't have any luck.

Just wondering what the best frequency to tune the box for my DB1040DVC would be? I'm not exactly sure which spec that would be on the spec sheet? Everything I've found show's frequency as Fb, but thats not listed in the specs... Is that the frequency response @28-200Hz or the Fs @37Hz (both from manual). Whats the difference between these 2 specs? Is one a range and the other ideal? One of the calculators (http://www.reaudio.com/speaker_box/LPort_Box_Calc.html) for my dimensions is showing tuned freq of 29.05Hz.

I want to start building, but a little unsure whats needed for the sub. Saw something about lower being better, as long as its not below 20Hz...It's going to be a slotted box (my first attempt at building ported/slotted). Also, if i slant the face on a slotted box, will that mess with the outcome? Hopefully this all makes sense.

Before the questions arise, I will be using 3/4" MDF, and aware of the importance to make it solid/tight. The amp used is Kicker MX700.5 Marine and this set-up is going in my boat, so box will be coated in rubberized coating.

Any help will be greatly appreciated. Thanks. :confused:
Post edited by ratchetdu on

Comments

  • ratchetdu
    ratchetdu Posts: 3
    edited January 2010
    Already checked out that site, but didnt get what i was lookikng for, or at least i dont think i did... Came up w a tuning frequency of 25.77Hz. Seems really low to me...

    All i want is the tuning frequency of a ported box for the DB1040DVC. Fs is 37Hz and i'm thinking i should be closer to this...
  • Jstas
    Jstas Posts: 14,707
    edited January 2010
    Unless you are going for an SPL competition, you should be tuning to the resonance of the sub and enclosure for peak efficiency overall, not just the sub. The Fs is a good guide but if you are tuning to that resonance then you need to consider box dimensions. Often times, space is at a premium so an enclosure cannot be as large as it needs to be to accommodate the Fs of the speaker itself. So you go for the next best thing and tune to a harmonic that compliments the Fs.

    It also depends on what you want to do. If you want loud then you need a big box and big ports. If you want clean, fairly tight bass that isn't overly boomy, you need a small box with a smaller port and that is going to drag the tuning frequency way down.

    For a first time builder, I'd recommend a sealed enclosure. They are much more forgiving as you learn what works and what doesn't.

    Here is the best reference on the Intarwebs for all things car audio related: http://www.the12volt.com/

    Lots of good info there. very recommended for a novice.
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  • Chase lapsed
    Chase lapsed Posts: 17
    edited January 2010
    Jstas wrote: »
    Unless you are going for an SPL competition, you should be tuning to the resonance of the sub and enclosure for peak efficiency overall, not just the sub. The Fs is a good guide but if you are tuning to that resonance then you need to consider box dimensions. Often times, space is at a premium so an enclosure cannot be as large as it needs to be to accommodate the Fs of the speaker itself. So you go for the next best thing and tune to a harmonic that compliments the Fs.

    It also depends on what you want to do. If you want loud then you need a big box and big ports. If you want clean, fairly tight bass that isn't overly boomy, you need a small box with a smaller port and that is going to drag the tuning frequency way down.

    For a first time builder, I'd recommend a sealed enclosure. They are much more forgiving as you learn what works and what doesn't.

    Here is the best reference on the Intarwebs for all things car audio related: http://www.the12volt.com/

    Lots of good info there. very recommended for a novice.

    is there a good book out there that can tell me about what all the terms are and as well to explain more about what were talking about ?
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  • mrbigbluelight
    mrbigbluelight Posts: 9,197
    edited January 2011
    reported
    Sal Palooza
  • JimAckley
    JimAckley Posts: 1,138
    edited January 2011
    is there a good book out there that can tell me about what all the terms are and as well to explain more about what were talking about ?

    Loudspeaker Cookbook. Or just use the internet. There are a handful of quick guides that people have written up that explain this stuff. Personally I learned most of what I know from the Loudspeaker Cookbook. It's pretty in depth.
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