Old cabs w/New Speakers/DIY adventure club....the good, bad and the fugly.

Discussion in 'Amps and Cabs [BG]' started by Stumbo, Oct 10, 2012.

  1. Stumbo

    Stumbo Wherever you go, there you are.

    Feb 11, 2008
    So. Cal.
    With so many recent threads on the topic, I thought it would be interesting (and a great information source) to get as many detailed posts/pics/clips as possible about updated/DIY cabs in one mega thread. Or, if you know of a recent thread, have a thread already or planning on starting one, take a second and post a link here. :)

    Let's see your project(s)! :bassist:

    Here are a few links to start things off:
    JohnK_10 http://www.talkbass.com/forum/f15/custom-diy-2x15-cab-build-854517/
    Jmac http://www.talkbass.com/forum/f15/jmacs-nidacore-composite-215-cab-build-thread-877782/
    Chokeslam512 http://www.talkbass.com/forum/f15/yet-another-diy-cab-thread-597736/
    Stumbo http://www.talkbass.com/forum/f15/new-era-diy-cab-builders-cabs-needing-replacement-speakers-861927/
    SBrown http://www.talkbass.com/forum/f15/another-d-i-y-cab-project-quest-light-gear-808851/
    Rhythm5 http://www.talkbass.com/forum/f15/diy-speaker-threads-438514/
    gimp http://www.talkbass.com/forum/f15/peavey-2x15-project-complete-823227/
    fEARful TB wiki Builds in progress or completed
    greenboy website: http://greenboy.us/fEARful/
  2. ThisBass


    Aug 29, 2012
    Some important information for all DIY.

    WinISD and WinISD pro calculates erroneous dimensions for the vents.

    The error increases dramatically with the number of speakers.

    If there is only one speaker in a given box then the vent dimensions seem to be ok.
  3. CL400Peavey

    CL400Peavey Supporting Member

    Nov 7, 2011
    Grand Rapids Michigan
    First I have heard of this. Care to back up this statement with a source?
  4. ThisBass


    Aug 29, 2012
    The implementation for the Helmholtz-Resonator seems to be wrong.

    I myself had problems with erroneous vent dimensions some years ago.
    A prof cab designer here in Germany told me the reason is erroneous WinISD.

    Since this happened I give more trust to a simulation software that is also used by Emminence.
    The OEM version is from HT Audio.

    Pull up any Emmince cab design from their website and try to compare with WinISD.
    The vent dimensions are very different.

    If I remember correctly,
    the calculated vent length for a given fb is far too long.
    2 speakers approx. +40% error
    4 speakers approx. +70% error

    If you don't know what you don't then it is not mandatory audible that the vent length is bit too long for a designed fb.

    The lower frequency response lacks a little bit but the lack is not dramatically for a 210/212/215 cab.
    By the other hand it is good practice IMO to do the fine tuning for the vents length with the ears.
    So if the length is a bit too long calculated but the ears say the length should be a little bit shortened ....
    Of course it needs some experience to do like that and yield the goal.
  5. Passinwind

    Passinwind I Know Nothing Supporting Member

    Greenboy has documented it pretty well for the case of shelf ports.
  6. CL400Peavey

    CL400Peavey Supporting Member

    Nov 7, 2011
    Grand Rapids Michigan
    Good to know. Shelf ports only or does it work with cylinders as well?
  7. Passinwind

    Passinwind I Know Nothing Supporting Member

    I got tired of searching for links to my own DIY project threads over and over, so I'm slowly porting all the pics and documentation over to my own website: http://passinwind.com .
  8. Passinwind

    Passinwind I Know Nothing Supporting Member

    Not sure, but I always measure actual tuning for myself and then let my ears ultimately decide anyway.
  9. will33


    May 22, 2006
    Never had a problem with WinISD and round ports. They've all come in as expected, or within the small tolerance that the human ear can't tell the difference.

    Did have a problem getting a shelf port to act right though. As I understand it, there is a bit of the cabinet walls acting as a port "lengthener" when the port is particularly short in height compared to it's width, or maybe just shelf ports that don't have much height in general.

    Some discussion of it in this thread. http://www.talkbass.com/forum/f15/cab-building-question-about-shelf-port-length-823673/

    This online calculator http://www.carstereo.com/help/Articles.cfm?id=31 is said to be more accurate with the shelf ports.

    Ironically, when doing some preliminary modeling on my next build, the car audio calculator and WinISD both gave me the same length for some 2" x 5" shelf ports. The car audio calculator will not accept measurements that have a height to width ratio of greater than 1 to 8. WinISD will. Perhaps that has something to do with the inaccuracies?

    Never done a really detailed build thread here. The next one (if I can ever get damn time to do it), I will take photos, do some step-by-step and explanations. Will include final measurements vs. modeling program predictions, etc. Don't expect it anytime soon though. Ah...life gets in the way sometimes....such is life.:)
  10. astack

    astack Supporting Member

    Nov 12, 2011
    Washington, DC
  11. ThisBass


    Aug 29, 2012
  12. Stumbo

    Stumbo Wherever you go, there you are.

    Feb 11, 2008
    So. Cal.
  13. Stumbo

    Stumbo Wherever you go, there you are.

    Feb 11, 2008
    So. Cal.
    Any more DIY cabs finished? In process? Thinking about? New threads to link?
  14. Stumbo

    Stumbo Wherever you go, there you are.

    Feb 11, 2008
    So. Cal.
  15. BogeyBass


    Sep 14, 2010
    I did this really ugly 2x15 thread as a experiment

    Have a extra pair of Eminence 3015's
    and plan on starting the 2x15 build tomorrow.

    Thread will follow of course.
    This one is serious build too.
  16. I inherited an old Traynor 2x15 PA cab. I bought some re-coned EV Force 15s. I added some batting, plugged one of the 1/4" holes in the cab and added the EVs. At low volume, the cab sounds awesome. At high volume it sounds like it's falling apart.

    Then I did something... Plugged my son's Epi Valve jr into the 2x15 and holy crap it sounds awesome! So awesome that I can't wait to get another guitar head & run it through that cab. Little discoveries like that are kinda fun.