Help Rewiring an 8x10.

Discussion in 'Amps [BG]' started by mrkreuzschlitz, Jul 24, 2008.


  1. mrkreuzschlitz

    mrkreuzschlitz

    Joined:
    Jun 30, 2008
    Messages:
    1,343
    Location:
    Dacula, GA
    I have to completely rewire an 8x10 cabinet, literally. Haha I can't figure it out, I have eight 8 ohm speakers, and I need to get a 4 ohm load. I want to wire it like its two 8 ohm 4x10 cabs, and then wire those to together to make it 4 ohms.


    I can't for the life of me figure this out, anybody have a diagram or can help me?

    Oh, by the way, my band is playing a show saturday afternoon, and I need my cab.

    :bag:
     
  2. Bass_Pounder

    Bass_Pounder

    Joined:
    Jan 19, 2002
    Messages:
    3,644
    Location:
    Palm Coast, Florida
  3. Vintage-Blue

    Vintage-Blue Gold Supporting Member

    Joined:
    Feb 13, 2008
    Messages:
    712
    Location:
    Cincinnati, OH
    Disclosures:
    Owner, Vintage Blue (repro cabinets)
    I believe you should be able to wire the top pair of speakers together in series, giving you a 16 ohm load. Do the same with each of the other 3 pairs of speakers and you should end up with 4 pairs of speakers, with each pair having an impedance of 16 ohms. Connect the pairs together in parallel and you should have a 4 ohm load.
     
  4. mrkreuzschlitz

    mrkreuzschlitz

    Joined:
    Jun 30, 2008
    Messages:
    1,343
    Location:
    Dacula, GA
    Thank you guys SO much. I'm replacing all of the speakers in the fridge with some cheaper ones that aren't as heavy :meh:, but they aren't blowing voice coils left and right. (they're not good speakers either, but the new ones aren't blowing up on me)

    Also, how long should it take the speakers to break in, and how will I know?
     
  5. Register to disable this ad
  6. Kenbuntu

    Kenbuntu

    Joined:
    Jun 6, 2005
    Messages:
    1,529
    Location:
    Ontario
    Uh, depends. Some people just run a looped track anywhere from 10-24 hours. It depends on the cones material, if it's stiff or not etc. I know theres a program for this but i cant remember its name.

    As for the frequency. It should be a frequency where max excursion is present, meaning its moving as far as it can without farting out. It's not necessary to get say, 6.2mm out of 6.2 mm, but its good to get them moving. throw some salt on them. If the grains aren't jumping around, lower the frequency.

    someone correct me if I'm wrong
     
  7. mrkreuzschlitz

    mrkreuzschlitz

    Joined:
    Jun 30, 2008
    Messages:
    1,343
    Location:
    Dacula, GA
    Thanks. Anybody have any ideas on songs to just play over and over?
     
  8. Kenbuntu

    Kenbuntu

    Joined:
    Jun 6, 2005
    Messages:
    1,529
    Location:
    Ontario
    just burn a cd with a frequency on it and let it play while you go to work, when you get back home, and a few hours after that, you should be good to go.
     
  9. mrkreuzschlitz

    mrkreuzschlitz

    Joined:
    Jun 30, 2008
    Messages:
    1,343
    Location:
    Dacula, GA
    okay, i made a wiring diagram. this what i want, correct?


    [​IMG]


    In hertz, what would a good frequency be?
     
  10. Kenbuntu

    Kenbuntu

    Joined:
    Jun 6, 2005
    Messages:
    1,529
    Location:
    Ontario
    The diagram looks right. so does the math. as for the frequency i think 32 Hz should be fine but its an educated guess. What speakers are they?
     
  11. Rick Auricchio

    Rick Auricchio Registered Bass Offender Supporting Member

    Joined:
    Nov 27, 2007
    Messages:
    4,748
    Location:
    Cambria, CA (Central Coast)
    You really should break in the drivers outside the cabinet. Otherwise it'll be loud as hell, or shake things off the walls.
     
  12. mrkreuzschlitz

    mrkreuzschlitz

    Joined:
    Jun 30, 2008
    Messages:
    1,343
    Location:
    Dacula, GA
    I guess since I'll have to rewire it, I will.

    The speakers? Don't laugh,
    But they're Johnson brand speakers, 125 watts RMS, not sure of the frequency responce, but they have a snazy looking whizzer cone!

    I've already used one, and it sounds good. A shop near me buys TONS at a time and sells them for about $30 a pop. I know, they're no Eminence, but its all I can afford. I'm saving up for a Peavey Tour 810 after this, and I'd LOVE an Aguilar GS412, but money ain't the best right now.
     
  13. Kenbuntu

    Kenbuntu

    Joined:
    Jun 6, 2005
    Messages:
    1,529
    Location:
    Ontario
    Don't worry, if i had a store like that, i'd do the same. Just start at 30 Hz. Listen to it on your computer through headphones, and kind of "eyeball" it in the sense that if it sounds like it'll harm the speakers just go up a few cycles.

    And it doesn't need to be to loud. Just enough so that the cone moves, and do the salt test.

    Actually when i think about it, the lower the freq is, the bigger the travel. so technically you could probably do it a bit lower, but dont turn it up to loud, other wise, there go the speakers. Haha, just stick to the 30's just to be sure. And break them in outside of the box. Otherwise you'll be pushing some serious air.
     
  14. mrkreuzschlitz

    mrkreuzschlitz

    Joined:
    Jun 30, 2008
    Messages:
    1,343
    Location:
    Dacula, GA
    Well right now i'm running one at 32 hz, seems to be the magic number. The cone is MOVING a lot, and i think its a good thing. I can feel a hum when I get close, but its not annoyingly loud. I was running it a full 350 watts, but after a few seconds I realized that maybe that isn't the best idea considering the speaker's handling. So, I'm just letting it play turned up about 3/8ths of the way, and it seems to work really well. I don't even have to do the salt test, its moving a lot. I'm gonna break in the rest tomorrow night because if somehow these speakers screw up, I'd rather have a bunch that work but don't sound amazing and one that doesn't work at all than a bunch that don't work. I doubt it can happen, but it couldn't hurt to ensure.
     
  15. Kenbuntu

    Kenbuntu

    Joined:
    Jun 6, 2005
    Messages:
    1,529
    Location:
    Ontario
    yeah, just make sure not to run too much power through them and you'll be fine.

    Time to get some sleep!
     
  16. Rick Auricchio

    Rick Auricchio Registered Bass Offender Supporting Member

    Joined:
    Nov 27, 2007
    Messages:
    4,748
    Location:
    Cambria, CA (Central Coast)
    No need to run that much power.

    Slap an AC voltmeter across the speaker terminals and adjust to 10-12 volts. If the cone moves too much, pull back a bit.
     
  17. mrkreuzschlitz

    mrkreuzschlitz

    Joined:
    Jun 30, 2008
    Messages:
    1,343
    Location:
    Dacula, GA
    Eh, I don't have an AC voltmeter, and I can use my power amp just fine. Its working pretty well so far.

    :bassist:
     
  18. Vintage-Blue

    Vintage-Blue Gold Supporting Member

    Joined:
    Feb 13, 2008
    Messages:
    712
    Location:
    Cincinnati, OH
    Disclosures:
    Owner, Vintage Blue (repro cabinets)
    I'm confused about the purpose of the second input, the one on the right. If nothing else, it looks as if it is wired as a dead short. :confused:
     
  19. Alexander Eddy

    Alexander Eddy

    Joined:
    Oct 10, 2005
    Messages:
    462
    Location:
    Out in the the bush, Australia
    Your diagram is incorrect. All is fine except for your second (the one on the right) input. The input on the left it a single 4 ohm input for all 8 speakers. DO NOT wire up that second input, you will only blow an amp. Sorry I cant draw you a diagram, I dont have access to CAD at the moment. Hopefully someone else can chime in wth a pic
     
  20. Femto

    Femto

    Joined:
    Jul 5, 2003
    Messages:
    427
    Location:
    Keighley, W.Yorkshire, England
    The only reason that I can see for the two jack sockets on your cab would be so you could connect another cab. For that, you would just need to wire both sockets to exactly the same terminals as if you only had one socket. Hence, the sockets would be in parallel.

    This would mean you could run your 8x10 and another cab that had the same impedance as your 8x10. This would present a 2 ohm load to your amp of course so if you did that, your amp would need to be designed to work safely at 2 ohms. The Ampeg SVT-CL will, so will the VR. The Marshall VBA400 will. Lots of SS power amps will too.

    + AMP -
    |.........|
    + 8x10 -
    |.........|
    + 8x10 -

    The dots are there so I could get the vertical bars to stay apart. Pesky HTML!
     
  21. mrkreuzschlitz

    mrkreuzschlitz

    Joined:
    Jun 30, 2008
    Messages:
    1,343
    Location:
    Dacula, GA
    Well thats how the jack is wired now, I just don't have all the speakers wired. It came that way, its just so you can use either input. I'm thinking about taking one out and replacing it with a good ol speakon.

    Now another 8x10? Buy me one, and hmmm.... An Ampeg SVT-VR or whatever the model is and I'll gladly run both cabs at 2 ohms. :D

    I'm not a HUGE fan of the CL. Too muddy for my tastes, but I like their VR.
    I'd still take the CL though. ;)
     

Share This Page