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4ohm + 8ohm?

Discussion in 'Amps and Cabs [BG]' started by spidersbass, Apr 18, 2005.


  1. spidersbass

    spidersbass

    Nov 29, 2004
    Downtown L.A.
    a friend of mine just got a Hartke vx215 (4ohm). so we put that under my vx410(8ohm) and powered it up with my HA4000, man, that sounded (and felt) sweet :bassist: .

    i just wanted to make sure of one thing... will putting these two cabs together of different ohms mess up my amp head? the head is rated at 400w at 4ohm, 300w at 8ohms. and when both cabs are connected, their in parallel. i just don't want to eff anything up with the ohm issue you know... thanks!
     
  2. Lowtonejoe

    Lowtonejoe Supporting Member

    Jul 3, 2004
    Richland, WA
    If your amp head has a 4 ohm minimum you will run the risk of frying it by hooking up these two speakers to it in paralell.

    8 ohms in paralell with 4 ohms = 2.67 ohms. Too low for your amp.

    Sorry dude.

    :D

    Joe.
     
  3. popinfresh

    popinfresh

    Dec 23, 2004
    Melbourne, Aus
    That makes 2.6 ohm. On an amp that goes to 4ohms. Not good.

    Edit: Joe beat me :)
     
  4. spidersbass

    spidersbass

    Nov 29, 2004
    Downtown L.A.
    dang, alright then.

    hmmm, :eyebrow: is there a way to rewire those vx215 speakers to make it an 8ohm cab? i dont' know what each individual speakers ohms is though, sorry.
     
  5. Lowtonejoe

    Lowtonejoe Supporting Member

    Jul 3, 2004
    Richland, WA
    More than likely they are 8 ohms each.

    That means your ohmage options are 4 ohm (paralell) or 16 ohm (series).

    If you hooked the speakers up in series and then made sure you had the phasing correct you could safely run both cabs together in paralell and get almost full power.

    However, if you ran the 215 by itself you would only get about half power.

    :D

    Joe.
     
  6. spidersbass

    spidersbass

    Nov 29, 2004
    Downtown L.A.
    how would i make sure this "phasing" is correct?

    oh, and if i run the 215 by itself at 16ohm, will it eff up the amphead?
     
  7. Lowtonejoe

    Lowtonejoe Supporting Member

    Jul 3, 2004
    Richland, WA
    In this particular situation by 'phasing' we just want to make sure that all your speakers are going in at the same time and going out at the same time. If one or more speaker is 'out of phase' with the rest you will lose a substantial amount of bass.

    1. Connect both cabs together with a speaker cable (no amp needed).

    2. Make a pigtail with one end bare wire and a connector on the other.

    3. Plug the connector of the pigtail into one of your parallel jacks.

    4. Take a 9v battery and touch one wire to the plus side and one wire to the minus side at the same time.

    Your speakers will either move in together, move out together or some combination of this.

    If they all move in the same direction you're good to go. If they move opposite of each other you should rewire one cab (or speakers) to match the others.

    Good luck.

    And yes, you can run your amp at 16ohms per the manual.

    :D

    Joe.
     
  8. spidersbass

    spidersbass

    Nov 29, 2004
    Downtown L.A.
    alright, thanks everyone! :bassist:
     
  9. spidersbass

    spidersbass

    Nov 29, 2004
    Downtown L.A.
    wait, one more thing...

    how much power will i be pushing with my HA4000 connected to only the vx215 at 16ohms?

    thanks
     
  10. popinfresh

    popinfresh

    Dec 23, 2004
    Melbourne, Aus
    Just a question on this.. You know if you run 4+8 ohm cabs.. the 4ohm gets more power than the 8 right.. I can bi-amp my 1516.. So if i run 3 8ohm cabs into an amp that can run at 2 or 2.6.. will they all get the same power?
     
  11. Steve S

    Steve S

    Jul 26, 2000
    I have the Eden WT 550 that goes down to 2 ohms. How much power would go to a 4 ohm cabinet and how much to an 8 ohm if I play them together?
     
  12. Lowtonejoe

    Lowtonejoe Supporting Member

    Jul 3, 2004
    Richland, WA
    Probably about 1/2 the power of what you would get at 8 ohms.

    Them's the breaks.

    :D

    Joe.
     
  13. Lowtonejoe

    Lowtonejoe Supporting Member

    Jul 3, 2004
    Richland, WA
    Yes, three 8 ohm cabs connected in paralell into the same amp will all get the same power regardless of speaker power rating.

    But if they have different sensitivity levels one may sound louder than another.

    :D

    Joe.
     
  14. Lowtonejoe

    Lowtonejoe Supporting Member

    Jul 3, 2004
    Richland, WA
    With both cabs connected at the same time to the same amp you would get:

    4ohms = 2/3 power

    8ohms = 1/3 power

    :D

    Joe.
     
  15. Steve S

    Steve S

    Jul 26, 2000
    I have a WT 550 that pushes 500 watts into 4 ohms and I think 650 into 2 ohms. If I connect a 4 ohm Peavey 410 TVX and an 8 ohm GK 115 to it, will it sound ok. Do people mix ohms in their speakers? Would it be better to have both cabinets at 4 or 8 ohms?
     
  16. Lowtonejoe

    Lowtonejoe Supporting Member

    Jul 3, 2004
    Richland, WA
    If it sounds o.k. then it sounds o.k. Give it a try. Ohms don't effect tone.

    All that will happen is that your 410 will get about twice as much power as your 115.

    Now...if you don't like the way that particular mix sounds, don't do it. But it won't hurt anything to try since you say your amp can go down to a 2 ohm load.

    And just FYI I run my 115 and 210 cab together for big gigs and the 115 is 8 ohms and the 210 is 4 ohms. I run in stereo so I can adjust the mix and I have never had a problem with it.

    :D

    Joe.
     
  17. Steve S

    Steve S

    Jul 26, 2000
    Thanks Joe..I understand how ohms works now and what you mean about the sound if one speaker receives more watts than the other.
     
  18. Funkengrooven

    Funkengrooven Turn it down? You gotta be nuts!!

    See my response to bassjunior
     
  19. Lowtonejoe

    Lowtonejoe Supporting Member

    Jul 3, 2004
    Richland, WA
    Cool.

    I aim to please. Sometimes I miss but I aim to please.

    Hope I was helpful.

    :D

    Joe.