Closed Thread
Page 1 of 2 1 2 LastLast
Results 1 to 15 of 16

Reload Thread: Is there a way to empirically test the tuning of an enclosure?

  1. #1
    jibberjive's Avatar
    jibberjive is offline Senior VIP Member



    Join Date
    Jan 2002
    Location
    SLC, UT
    Posts
    206
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    0 Post(s)

    Is there a way to empirically test the tuning of an enclosure?

    As the title says, is there an empirical means of finding the tune of an enclosure other than using the math (or box building program) and the enclosure volume, port area and length?







  2. #2
    audioholic's Avatar
    audioholic is offline Moderator



    Join Date
    Aug 2003
    Location
    Parts Unknown
    Posts
    23,586
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    320 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    You want a way to find a mathematical answer without using math? I guess you could try praying to God for the correct answer. Im really not following what you think you want here.



    No speaker, in the history of speakers, has ever been blown by too little power. Ever. I don't care what your friend told you, he's a dirty liar.


  3. #3
    jibberjive's Avatar
    jibberjive is offline Senior VIP Member

    Threadstarter


    Join Date
    Jan 2002
    Location
    SLC, UT
    Posts
    206
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    0 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    Quote Originally Posted by audioholic View Post
    You want a way to find a mathematical answer without using math? I guess you could try praying to God for the correct answer. Im really not following what you think you want here.
    No, I'm curious if there's another way to test it other than the math (ie. measuring port mach or something).




  4. #4
    Twistid's Avatar
    Twistid is offline 150.5



    Join Date
    Jun 2004
    Location
    in a space out of sound
    Posts
    9,588
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    4 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    play test tones , where the subwoofer moves the most is the usual tuning



    "A modest little person, with much to be modest about."
    Winston Churchill

    REFS: Spicmonster(buyer), playa1(buyer), splthunder(buyer), 949runner (seller), dbman150 (trade), pbulous (trade), bumpin97jeep(trade) , spudracer326 (seller) , 99stanggt (seller) , xplicitACTS (trade) ... and forgetting a few others
    BHCSAOWKF

  5. #5
    helotaxi's Avatar
    helotaxi is offline Kilroy was Here



    Join Date
    Dec 2003
    Location
    South Central (New Mexico that is...)
    Age
    39
    Posts
    8,933
    Post Thanks / Like
    Images
    4
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    0 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    Actually it's where it moves the least. You can test it in the same manner as the T/S parameters are tested, but you need to already know the T/S parameters and then do the math backwards to figure volume. Tuning though is easy, wire a resistor in series and then measure the voltage across the resistor using a series of test tones. Where the voltage drop across the resistor is the least, the impedance of the driver is at its max and that the the resonance point of a ported enclosure. It works exactly the opposite for a sealed box.



    Artificial Intelligence is no match for Natural Stupidity.

    Never underestimate the power of stupid people in large numbers.

    Life's tough...it's even tougher when you're stupid.

  6. #6
    Volenti's Avatar
    Volenti is offline Senior VIP Member



    Join Date
    Feb 2006
    Location
    Australia
    Posts
    271
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    0 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    Quote Originally Posted by helotaxi View Post
    Actually it's where it moves the least. You can test it in the same manner as the T/S parameters are tested, but you need to already know the T/S parameters and then do the math backwards to figure volume. Tuning though is easy, wire a resistor in series and then measure the voltage across the resistor using a series of test tones. Where the voltage drop across the resistor is the least, the impedance of the driver is at its max and that the the resonance point of a ported enclosure. It works exactly the opposite for a sealed box.
    Yes, do this with the enclosure both outside and inside the car, and notice the difference in frequency and impedance value.




  7. #7
    ngsm13's Avatar
    ngsm13 is offline BSEE



    Join Date
    Sep 2002
    Location
    Cincinnati, OH
    Posts
    35,730
    Post Thanks / Like
    Images
    20
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    65 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    Quote Originally Posted by Twistid View Post
    play test tones , where the subwoofer moves the most is the usual tuning
    Completely and utterly incorrect.



    nG




    http://crunktimes.com/ct/
    nG - BSEE

  8. #8
    Immacomputer's Avatar
    Immacomputer is offline Cloud disappear



    Join Date
    Sep 2006
    Location
    Ocala/Oviedo, FL
    Age
    30
    Posts
    4,670
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    12 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    It's very simple to just play some tones about .5hz apart and check for the least amount of cone movement.

    I usually do this with a signal generator after I finish an enclosure to see how close the final product turned out.



    Video 1
    I may make you feel but I can't make you think.
    Your sperm's in the gutter -- your love's in the sink.
    Video 2

  9. #9
    jibberjive's Avatar
    jibberjive is offline Senior VIP Member

    Threadstarter


    Join Date
    Jan 2002
    Location
    SLC, UT
    Posts
    206
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    0 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    So the difference in excursion is distinguishable even up to .5 hz I take it then.
    Quote Originally Posted by Twistid View Post
    play test tones , where the subwoofer moves the most is the usual tuning
    No need for me to say it again since it's been said twice

    Volenti, so the environment outside of the enclosure affects the impedence rise of the enclosure as well? I thought just the enclosure affected it, but idk




  10. #10
    Volenti's Avatar
    Volenti is offline Senior VIP Member



    Join Date
    Feb 2006
    Location
    Australia
    Posts
    271
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    0 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    Quote Originally Posted by jibberjive View Post

    Volenti, so the environment outside of the enclosure affects the impedence rise of the enclosure as well? I thought just the enclosure affected it, but idk
    Yes indeed, the last vented enclosure that I did detailed measurements on had a tuning frequency of 47.5hz @ 14.4 ohms impedance (dual 4ohm sub, coils in parallel) in half space (box sitting on the ground) and a tuning frequency of 45hz @ 10.95 ohms rear firing in the boot of my small sedan.

    Even bigger changes can be seen in more exotic enclosure designs like transmission lines and horns.




  11. #11
    helotaxi's Avatar
    helotaxi is offline Kilroy was Here



    Join Date
    Dec 2003
    Location
    South Central (New Mexico that is...)
    Age
    39
    Posts
    8,933
    Post Thanks / Like
    Images
    4
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    0 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    Since the car is a small space, the air in the cabin of the car will affect the movement of the cone since it acts as another part of the enclosure. The cabin will thus affect the tuning of the enclosure and the response of the system.



    Artificial Intelligence is no match for Natural Stupidity.

    Never underestimate the power of stupid people in large numbers.

    Life's tough...it's even tougher when you're stupid.

  12. #12
    PV Audio's Avatar
    PV Audio is offline The Vision of Sound



    Join Date
    May 2004
    Location
    Indy
    Age
    25
    Posts
    19,655
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    0 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    Quote Originally Posted by Twistid View Post
    play test tones , where the subwoofer moves the most is the usual tuning
    You're merely boosting your output in that frequency range, not boosting speaker excursion. A frequency much lower than tuned in a large box will move quite more than the Fb.




  13. #13
    JohnBlayz142's Avatar
    JohnBlayz142 is offline CarAudio.com Elite



    Join Date
    Nov 2005
    Location
    Naples, FL
    Posts
    861
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    0 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    Quote Originally Posted by Twistid View Post
    play test tones , where the subwoofer moves the most is the usual tuning
    Here for 3 years and you still have this backwards? Just proves post count means nothing around here.




  14. #14
    Decipha's Avatar
    Decipha is offline www.EFI Dyno Tuning.com



    Join Date
    Mar 2005
    Location
    New Orleans, LA
    Age
    26
    Posts
    3,263
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    2 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    post count just determines how much time u spend on the forum

    i've seen people here as long as me with over 10k



    supercoupe enthusiast x9

  15. #15
    jibberjive's Avatar
    jibberjive is offline Senior VIP Member

    Threadstarter


    Join Date
    Jan 2002
    Location
    SLC, UT
    Posts
    206
    Post Thanks / Like
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quoted
    0 Post(s)

    Re: Is there a way to empirically test the tuning of an enclosure?

    Quote Originally Posted by Decipha View Post
    post count just determines how much time u spend on the forum

    i've seen people here as long as me with over 10k
    eh, not necessarily. Some people post alot, some don't. I've spent my fair share of time on the forum, yet I don't have an insane high post count.




Closed Thread
Page 1 of 2 1 2 LastLast

User Tag List

Posting Permissions

  • You may not post new threads
  • You may post replies
  • You may post attachments
  • You may edit your posts
1e2 Forum