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cabinet question

Discussion in 'Amps and Cabs [BG]' started by blong1, Oct 23, 2000.


  1. blong1

    blong1 Supporting Member

    Apr 10, 2000
    Alabama
    hi all!

    maybe this is in the right forum. i have a question for some of you wiring gurus because i don't have the slightest idea.
    i have a 2x10 peavey cab (4ohm) and i am about to get a 15" peavey cab (4ohm) only because i am getting a great deal on it. now, my question is...can these cabinets be converted to 8 ohm cabs. i can't push 2 4ohm cabs with my amp, but it will push 2 8ohm cabs. if this can be done, is it alot of trouble to do, or should i just trade in for 2 8ohm cabs. how much would it cost to have it done. thanks in advance.
     
  2. Your 2x10 is most likely two 8 ohm speakers wired in parallel and can't go anywhere else but to 16 ohms. The 15 is probably just a 4 ohm driver. It is possible to change the voice coil of a speaker to make it a different impedence but I wouldn't go doing that to a perfectly good speaker. About the only thing you could do would be to wire the two cabinets in series for an 8 ohm load but I've heard that's not really a good idea with mismatched cabinets.

    Basically, you're screwed. Get two new 8ohm cabs or buy a second power amp.
     
  3. White_Knight

    White_Knight

    Mar 19, 2000
    USA
    Don't know about prices, but I'd try to trade out your cabinents or buy a power amp that can handle a 2 ohm load (mono) or a stereo power amp that handles at least 4 ohms per channel.
     
  4. You could use a power amp to drive the second speaker. or slave two amps and drive the second speaker this way. If your realy lucky your amp has a crosover output to drive to drive another amp.
     
  5. blong1

    blong1 Supporting Member

    Apr 10, 2000
    Alabama
    thanks for the replys people. sounds like the easiest thing to do is just get different cabs. oh well...anybody need some 4ohm cabs???
     
  6. Munjibunga

    Munjibunga Total Hyper-Elite Member Gold Supporting Member

    May 6, 2000
    San Diego (when not at Groom Lake)
    Independent Contractor to Bass San Diego
    Seems to me that a simple solution would be to connect the two 4-ohm cabs in series for 8 ohms. You need to make (or buy) a special cord for this, but it ain't that hard. I think Bass Player had a how-to on this a couple months ago. It should work.
     
  7. Munjibunga is right run them in SERIES which will give you 8ohmes in total. For details on the special cable go to http://www.bassplayer.com then click on GEAR then scroll down to the 13'th articale on the left titled IMPEDANCE. It worked well for me.

    [Edited by pkeeg on 10-25-2000 at 08:36 PM]
     
  8. blong1

    blong1 Supporting Member

    Apr 10, 2000
    Alabama
    sweet!!! i'm going to try to wire them in series first and see how it sounds. thanks guys.
     
  9. From what I've heard, it's not a good idea to run two different speaker cabs in series. It's fine to run in series if all the speakers in the line are identical. But if they're not, you could get some unexpected results. The speakers will react to each other and the result could sound less than desirable.
     
  10. blong1

    blong1 Supporting Member

    Apr 10, 2000
    Alabama
    what do you mean by "less than desirable"? will it damage my speaker or my amp? or just sound like crap?
     
  11. I don't know from personal experience. This is just what I heard. I don't think it would damage anything. I think you would just get weird phasing effects if one speaker is more efficient than the other. I guess that as one speaker sucked up the juice the other would get less power and it would vary with frequency. You can try it. You've got nothing to lose as long as you wire it correctly. Make sure you get the polarity right and don't put them out of phase with each other. If you did that it would definitely sound like crap.

    The other problem is that with an 8 ohm load you won't be using all the power of your amp anymore. You'd be adding a speaker but cutting the power at the same time. It might sound fuller but not any louder.

    Good luck man.

    P.S. I still think your best option is to get a seperate power amp.
     
  12. blong1

    blong1 Supporting Member

    Apr 10, 2000
    Alabama
    your're probably right. i'm going to try the wiring thing and see what it sounds like first (try to go the cheapest route first). if that doesn't work and sounds bad, then i'll go with the power amp...i'll let you know what happens. thanks everybody for your input.
     
  13. blong1

    blong1 Supporting Member

    Apr 10, 2000
    Alabama
    ok, so i've got the 15" cab (it is actually an older peavey combo with the amp and speaker shot). i replaced the speaker basket last night with a new black widow, following the direction exactly. then i go to plug it into my amp just to test it out and nothing. no sound or anything from the cab. what could be some possible causes for that? i'm pretty sure i hooked the wires back to the speaker correctly. any suggestions that i can do myself before i take it in and have someone look at it?