My Homegrown Cabs

Discussion in 'Amps and Cabs [BG]' started by rllefebv, Aug 12, 2002.

  1. rllefebv


    Oct 17, 2000
    Newberg, Oregon
    After coming to the conclusion that 10's weren't for me, I decided to build a pair of 1X15 cabs and get back to simpler components...



    The construction is 3/4" 7 ply birch plywood, dadoed and rabbetted joinery, stackable corners, spring loaded handles, 12 Ga. wiring throughout, caulked seams, etc... Initially, I was going to cover them with black carpet, but my son, with his 14 years of wisdom, convinced me to keep them wood. He kinds digs that 'HomeMade' vibe... Glad that I listened. The matching 3 rack-space box holds my Carvin R600 with room left for my soon to be ordered tuner...

    The speakers are Eminence Kappa 15LF's... box volume is the recommended 3.9 cu. ft. with three 2 7/8" ports to give a vent mach of .04... AcoustaStuff fiber lining the walls, about 2 lbs per cab, (it only looks as though it's right against the ports... They're clear for 3"). I'm pretty lame with WinISD, so I don't even have a guess as to the tuned freq of the cabs... Somewhere below 48Hz... I just know that they sound massive...

    I finished them yesterday morning in time for an outdoor party hosted by a local drummer that I jam with from time to time. I was pretty anxious to hear them in a band-type setting and wasn't disappointed. Of the six bassists in attendance, three of us brought rigs but everybody wanted to try mine! It ended up as the player for everybody's sets, so I got to hear it with a variety of styles and from varying positions around the field. I was very happy with the way they sounded. Surprisingly bright when someone played slap, (definitely not me!), deep, clear lows through the B of a Musicman 5. Punchy as hell with my P-Bass. Can't wait to try them next weekend at an outdoor party with my band.

    As for the grills, I'm thinking maybe a cane-type cloth, but my kids and some folks from work have me leaning very heavily towards a tie-dye grill. That would be cool for those Grateful Dead tributes, huh?

  2. they look good, you should be proud.
    how did you know the port size to make?
    and with the fiber, stuffing, how did you know how much to put in...
    i am making a speaker cab for my 15, it has to have an internal volume of 150 litres (which is 5.28 cubic feet) and the port size is one port 6 inches diameter and 5 3/8th inches long. now with the stuffing can i make the cab smaller, but still acousticly sounding the same?
  3. Mara


    Jan 11, 2001
    It's a very nice looking rig you've made, well done!
  4. mans0n


    Jun 15, 2002
    wow that looks great, im envious. i think the tie-die idea would look amazing with the wood grain.. very good work there
  5. mikeboth

    mikeboth The last thing you'll ever see

    Jun 14, 2002
    Tallinn, Estonia
    Operator: prophecysound systems
    Nice work! How many hours did it take for you to put them together?

  6. Great! Beautiful! Wood! Transparent finish! 15s! A guy who knows his stuff! We should hang out together! Playing our homebrew equipment.....


    Edit: tip: you should try to keep those ports and their ends free of damping stuff (at least 4 inches of free space). Makes the air flow more freely from the inside of the cab into the ports...
  7. K Dubbs

    K Dubbs Just graduated from OSU, Go Bucks!

    Mar 16, 2002
    Toledo, Ohio
    Do you have to subtract the volume of the acoustastuff fiber when determining the volume of the wooden cabinet? Does the volume of the wadding not matter?
  8. Joris and rllefebv where did you get all that information about speaker design?
  9. check his site out he as info and some books u should think about buying.
  10. fast slapper

    fast slapper

    Dec 11, 2001
    Fresno, CA
    Those are homemade! Very nice! :cool:
  11. rllefebv


    Oct 17, 2000
    Newberg, Oregon
    Thanks for the replies folks! I again have to admit to a very limited knowledge of acoustical design. I downloaded a program called WinISD and plugged in the speaker's parameters. Then took the default design, toyed with different port sizes, asked questions, read many posts here, (literally a ton of information on the 'Amps' forum!!), and went for it...

    For the ports, I looked at what was available at Parts Express, decided on a workable size, (2 7/8"... I have a 3.25" hole saw which worked perfectly for cutting the holes), plugged it into WinISD, asked questions about 'Vent Mach and WinISD' which bgavin was kind enough to answer, worked that one out, (3 ports at 2.875" dia. X 3.75" len. for a VentMach of .04)... Deep bass response with no port noise!

    For the fiber-fill, I used the 'Acousta-Stuf' polyfil. Again, took the default of about 1/2 lb. per cubic foot of enclosure. I've read about keeping the fill at-least 1 port diameter from the opening, which I did. bgavin recommends using nylon netting to accomplish this which I will be doing this week. I was in a hurry on Saturday, so I just relied on the spray adhesive to do the trick. The fill is 3" from the port openings, it just doesn't look like it in the picture. When I put in the netting this week, I'll give it 4" of breathing room as Joris suggests.

    I didn't re-calculate the box size based on the fill, which may have been an error on my part. I've used the stuff on cabinets in the past to tighten up bass response as it claims and have been very satisfied with the results. I went ahead with it on that premise...

    I did want to come out with a pair of smaller, lighter, more portable cabinets than my current 1X15. The new cabs measure out at 20.5" X 23" X 18.75" compared to my old cab, (also home-grown), at 25" X 25" X 18.75". Switching from particle board to plywood made a difference too... even with a heavier driver, the new cabs tip the scales at 52 lbs. each compared to 79 lbs. for my 1X15.

    I tried to get tricky with the handles and place them in exactly the center of the magnet structure when lifting. I was pretty bummed after I cut the holes because they seemed too low, too far forward, and the cabinets swung top-heavy when they were empty. My son, the eternal optimist, kept insisting that they were fine and 'Hey, it'll only matter when you're moving them!'... Turns out that he's right again. The boxes balance perfectly when moving with the handles right where they're at!

    All in all, figuring design time, I'd say these took between 24 and 32 hours, not including waiting for the glue to dry. After admiring Joris' stuff for so long, it's gratifying to get a positive response to my own attempt! I second the recommendation to browse his site for some really top-drawer home-brewed equipment!

  12. they look great. I guess the only reason why companies put carpet on the cabs is to make them more roadworthy, because yours look sooo much better than carpet-covered cabs.

  13. They're much too pretty to take out of the house. :)
  14. BassMann2112


    Jun 21, 2002
    no doubt... These cab's are really nice looking. I guess they wouldn't be as road worthy without carpet covers. but for some select users that don't move their rig much or at all (like a studio set).......
    So.... When are you gonna start your own buisness?
    Good Luck :D
  15. rllefebv


    Oct 17, 2000
    Newberg, Oregon

    Actually, these are going to be gigged every weekend for the next 7 weeks... They load in and out of my car with very little trouble. Even so, I'm having a friend in the upholstery department at work make some heavy duty covers... Always money well spent!

  16. Matthias


    May 30, 2000
    Vienna, Austria
    Very nice, indeed.

    Look at my ugly duckling, sitting beneath my GK MB 150.
    But it does play and makes it a very small, light and comparatively loud rig :)
  17. patrickj


    Aug 13, 2001
    Baltimore, MD

    Very nice! What kind of bracing do you have inside the cabinets?
  18. ldiezman


    Jul 11, 2001
    yeas.. I agree with everyone here. they do look very nice.. any plans on making more in the future??