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8" speaker for custom cab?

Discussion in 'Amps and Cabs [BG]' started by tuBass, Jan 6, 2006.

  1. tuBass


    Dec 14, 2002
    Mesquite, Texas
    I know this is unusual, but I need a suggestion.

    I have a homemade (by somebody else) cab that I would to improve. It's a well built 2x8, but the person that built it used aluminum cones, and it's a 16 ohm. I'd like to upgrade the speakers , and also bring it to 8 Ohm.

    Could somebody give me a starting place to look? My plan is to upgrade this cab, and then get a ashdown mag 115 go with it. I would think a 2x8 and a 15 would sound really nice together.

    Or, I could be wrong... somebody help me out
  2. Crockettnj


    Sep 2, 2005
    North NJ
    ify ou post the dimensions of the cab, the thickness of the wood it's made out of, and the size/length of the port, if any, then i bet some people will be able to give you advice.

    eminence alpha8?
  3. tuBass


    Dec 14, 2002
    Mesquite, Texas
    OK, here's more info

    exterior width 20.5"
    Height 13"
    Depth 12"
    Port (rear) 4"

    Thickness of wood 3/4"

    anything else?
  4. Call the guys at Low Down Sound for some 8's. I've got one of their 4x8 cabs and it's got cozy warm low end! I originally got it for use w/a EUB, but I also pair it up w/a Schroeder 1212 for std electric bass and it fills in that pillowy low end that the Schroeder lacks. A great blend! Who woulda thunk it!! Not sure if you'll want to add a 15" box then but your rig would definitely sound deep.
  5. tuBass


    Dec 14, 2002
    Mesquite, Texas
    I'll call them... I've heard they do some great things with 8's

    I was told the warmth of the 15 would be a good metch for the quickness of the 8's. What would you suggest I get, maybe a 2x12?
  6. It just occurred to me that I actually bought the LDS 4x8 from Ralf Patterson who apparently does some X-over design for LDS as well as builds his own brand of cabs. He's fond of the 8's also and was great to deal with. I'm sure if you sent him a PM he would be helpful w/some good suggestions for you. His username here on TB is: rpatter
  7. MODNY

    MODNY Guest

    Nov 9, 2004
    eminence beta 8's

    i love mine, they slam!
  8. luknfur


    Jan 14, 2004

    I've been dinking with a small homebuilt cab for a while. I assume you're wanting the 8's for mid-top. To cover the low end from what I can tell you have to go at least to a 10 and there aren't many of those to select from. Most 8 low ends will be 50 -60 Hz at best. That is adequate for a lot of players and maybe your application. You can probably get a sub to go deep but it won't go much over 200Hz or so - which is of no interest to me. The best thing I've run across so far is a Vifa from a Mackie monitor that will drop to 42Hz to about 5kHz in about a 1 1/2 cf ported box.

    I don't know if this is relevant for you or not but good luck finding a low end 8 if so - and let me know if you do.
  9. tuBass


    Dec 14, 2002
    Mesquite, Texas
    I plan on adding a 15 to the rig, so the extreme low end of the 8's isn't really what concerns me. The only reason why I'm going with 8's in the first place is because it's easier to upgrade the speakers in the cab I already have then buy a new 2x10.
  10. usspeaker is a good place to look at a selection of pro audio speakers. I think that Eminence beta 8 speakers would be a good inexpensive upgrade to a cab of that size. If you go that route the 4 inch port should be about 4.5 inches long. If you plan to put more than 200 watts into this cab you should probably use a high pass filter at around 50hz.

    FWIW my 4x8 cab is loaded with Eminence alpha 8's and I am very pleased with the results.
  11. tuBass


    Dec 14, 2002
    Mesquite, Texas
    The beta's are a little more expensive than the alphas, which is not a big deal. Thew low range of the betas seem to be a lot better, taking a little off the highs. If I'm using a 300W amp, and plan on adding a 15, is there any reason for me to go one way or the other concerning the Alpha/beta debate?
  12. watspan


    Nov 25, 2002
    madison, wi
    I have an ampeg pr-1528he cab which has 2x8 on top w/ a 45 degree angled 15 in a deep kind of half-scooped cabinet. I bi-amp w/ a hartke 5000 and I think the 2x8 1x15 mix is real nice--especially as I can sweep the bi-amp output to "balance" off bewteen the 8's and 15.
  13. MODNY

    MODNY Guest

    Nov 9, 2004

    boo ya

    i was thinking of adding another 2x8 sans tweeter though, hows taht for a mini stack
  14. You know of course that the speakers and the cab should match? The characteristics of the speaker determine how big the cab must be (how many litres) and also how long the ports must be. If you simply replace speakers there is a risk that the results will not sound good.
  15. That's why I suggested the Beta 8 speakers. The cab dimensions were given near the top of this thread.
  16. MODNY

    MODNY Guest

    Nov 9, 2004
  17. tuBass


    Dec 14, 2002
    Mesquite, Texas
    so the beta suggestion was based on the cab, not the specs of the speaker? That's cool, thanks.

    How do you go about figuring this stuff out? Is there a formula page out there?

    BTW, I just measured the length of the port, it's 5"
  18. I am using a cab design program called Winisd. You can download it for free. The 4x5" port should be fine.
  19. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    The Alpha and Beta 8s are only available in 8 ohms. Get the Carvin PS8 (an OEM Beta 8) in 16 ohms, wire the pair in parallel.
  20. tuBass


    Dec 14, 2002
    Mesquite, Texas
    If I have 2 speakers now that are together 16 OHM, does that mean that they are 32 Ohm speakers, or wired in series?

    If speakers can be wired in series to leave the ohms unchanged, then could I still get the Betas?

    Sorry if these seem like stupid questions, I really don't know this stuff.