Closed Thread
Results 1 to 6 of 6

Reload Thread: 4th order bandpass ported chamber question

  1. #1
    DFW40's Avatar
    DFW40 is offline CarAudio.com Veteran



    Join Date
    Aug 2004
    Location
    Keller, TX DFW area
    Age
    40
    Posts
    2,057
    Post Thanks / Like
    Images
    10
    Mentioned
    0 Post(s)

    4th order bandpass ported chamber question

    What would be the response difference in two boxes one with a sealed chamber of 1 cube and the ported chamber 1 cube tuned to 55hz and the other box has the same size sealed chamber 1 cube and the ported chamber being .75 cubes and tuned to 55hz? In other words what would be the response difference on two chambers tuned to the same freq but on is larger than the other.







  2. #2
    Kangaroux's Avatar
    Kangaroux is online now I put on



    Join Date
    Dec 2010
    Location
    Maine
    Posts
    9,590
    Post Thanks / Like
    Mentioned
    82 Post(s)

    Re: 4th order bandpass ported chamber question

    The smaller the ported chamber the less peaky it is thus the less efficient it is. As you get closer to a 1:1 ratio the response becomes less peaky (notice I say less peaky and NOT "flat").

    IMO, a 4th isn't worth the time unless you do like a 1:1.5 ratio. You can play around with the tuning to get it so where your response starts to fall off the cabin gain of your vehicle picks it back up, so you can get it very peaky and efficient while still having a flat response because the vehicle's cabin gain evens it out. Also, 55hz is pretty high for a 4th...most people do 45-50. How do you know you want it at 55?




  3. #3
    DFW40's Avatar
    DFW40 is offline CarAudio.com Veteran

    Threadstarter


    Join Date
    Aug 2004
    Location
    Keller, TX DFW area
    Age
    40
    Posts
    2,057
    Post Thanks / Like
    Images
    10
    Mentioned
    0 Post(s)

    Re: 4th order bandpass ported chamber question

    Looking at the spec sheet for an IDQ v.3 and it had a 1:1 ratio on one example tuned to 61hz and it shows and in car response that is pretty close to the ported but not exactly the same. I have a trunk sub and there are too many rattles and the low end is not quite there like it was in my Camry plus it gets much louder with trunk open. I have done all the test with box position etc and even seats folded down helps but I was going to try a 4th order piping thru a 6x9 hole.




  4. #4
    pro-rabbit's Avatar
    pro-rabbit is offline Moderator pro-rabbit is a Supporting Member of the forum!

    pro-rabbit is a Supporting Vendor of the forum!

    Join Date
    Jan 2004
    Location
    OKC, OK
    Age
    32
    Posts
    12,395
    Post Thanks / Like
    Mentioned
    374 Post(s)

    Re: 4th order bandpass ported chamber question

    You will have lots of trial and error to get this build right, I don't see it being right the first time or any where close to be honest.




  5. #5
    DFW40's Avatar
    DFW40 is offline CarAudio.com Veteran

    Threadstarter


    Join Date
    Aug 2004
    Location
    Keller, TX DFW area
    Age
    40
    Posts
    2,057
    Post Thanks / Like
    Images
    10
    Mentioned
    0 Post(s)

    Re: 4th order bandpass ported chamber question

    Built the box .8 sealed and 1.1 ported with a 4 inch aero tuned to 50hz. I did not mess with going thru the 6x9 hole and just firing it back. It sounds very solid hits the lows and has massive punch on the upper end. I could not be happier. FYI I had the IDQ v.3 in a 1.3 cubed box before tuned to 32 hz and have to say in this trunk believe it or not the bandpass sounds better, goes lower and punches higher. I could be crazy but it seems like there is almost no cancellation and all I can attribute it to is the smaller radius of where the sounds is coming out has less cancellation than the sealed 15 I had which dispersed the sound waves wider earlier which maybe had to do with the cancelllation issues. Now when I open the trunk the sound goes down vs up as before. I am sure there will be some group delay issues but so far so good. This is all theory but this 10 is louder and more balanced than the sealed 15 ID v.3 so go figure. I might try a slightly higher tuning because it is easy to do for kicks and giggles. I tried a bandpass a couple of years ago and it did not work out and I could not get it right either way way to high and punchy rumblings around 50 hz but I think I got lucky on this one.




  6. #6
    DFW40's Avatar
    DFW40 is offline CarAudio.com Veteran

    Threadstarter


    Join Date
    Aug 2004
    Location
    Keller, TX DFW area
    Age
    40
    Posts
    2,057
    Post Thanks / Like
    Images
    10
    Mentioned
    0 Post(s)

    Re: 4th order bandpass ported chamber question

    Pro-Rabbit looks like you live in Okc I went to OU and go up to Okc for business often. You build boxes professionally what would you have done differently on the box just curious. Also do the ID specs on their site for bandpass just not work at all or sound terrible the graph shows a relatively even in car response compared with sealed and ported. I changed up the tuning and increased the sizes from the ID sight but it really worked out pretty well so far. I might check out your shop and work next trip up if that is cool. If you can build a box that sounds better I will buy it for sure I am always open to sounding better.




Closed Thread

Similar Threads

  1. (2) RE Audio 10" SX's in a 4th order bandpass ported through the rear deck of a Lexus
    By SHiZNiLTi in forum Car Audio Build Logs - Cars/Trucks/SUVs
    Replies: 37
    Last Post: 04-22-2011, 01:22 PM
  2. 4th order bandpass port area?
    By Supergumby5000 in forum Enclosure Design & Construction Help
    Replies: 12
    Last Post: 12-06-2009, 09:18 PM
  3. 4th Order Bandpass question
    By Boomintempo in forum Enclosure Design & Construction Help
    Replies: 6
    Last Post: 10-26-2009, 01:42 AM
  4. ported or 4th order bandpass
    By SWFL in forum Enclosure Design & Construction Help
    Replies: 28
    Last Post: 09-10-2009, 08:41 AM
  5. 4th order bandpass or ported clamshell?
    By tooloud4tv in forum General Discussion
    Replies: 7
    Last Post: 05-09-2008, 08:34 AM

Posting Permissions

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