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is my amp capable of pushing two 4 ohm spkrs?

Discussion in 'Amps and Cabs [BG]' started by Bjazz, May 15, 2003.

  1. Bjazz


    May 14, 2003
    i gots a peavey megabass, it gots a pair of outs for high output, and a pair for the low. They both say
    200 watts rms, 28.3v rms 4 ohm
    parellel spkr output 4 ohm min.
    What is parallel mean?
    can i run a 1 x 10 w/ a mid (both 4 ohm),(1-4 ohm
    and 1- 8 ohm),(both 8 ohm)
    Which would i get a better sound from?
    what would be the most powerful spkr i could get?

    with this amp and said cab design,is it better to run it full range or in the bi-amp mode.
    any help is appreciated.. :meh:
  2. you can either use two 8 ohm, or two 4 ohm cabinets, just don't ever use one of each . with 8 ohm cabinets hooked up to most amps, you only get about two thirds of the amp's rated output at 4 ohms, because it will present a "load", or resistance, which isn't a bad thing, necessarily, it just means less output for you. so with 200 watts, you really only get about 130 watts , but with a 4 ohm cab, you get the whole 200, capish?...and parallel just means plugging a speaker cabinet into channel one and another into channel two.:p

    bi-amping is something i've tried, but didn't like, my feeling is that:

    a) it doesn't benefit your sound one ounce
    b) it isn't great for your speakers
    c) it sounds horrible onstage
    d) your audience wouldn't notice

    others will have totally different opinions about this, but that's my two cents:D
  3. BryanB

    BryanB Moderator Staff Member Supporting Member

    You CANNOT use two 4 ohm cabs unless your amp is capable to handling a two ohm load. Most amps are not, so please check your amps specifications before plugging them in.
  4. yes, my bad...sorry

    if you're using a MONO amp, which i think you are, then your choices are:
    one 8 ohm cab, or
    two 8 ohm cabs, or
    one 4 ohm cab

    i was on drugs, when i posted that. but everything in that post still holds true if you'd had a STEREO head, or a power amp....oops:meh:
  5. its peavey man, most peaveys take 2 ohm loads, and that's the problem... you have to have a 2 ohm load to pull out the intended amount of power and that blows in my opinion. So when you try using a quality amp you most likely end up using half the cabs. I hope none of you come screeming back to me about how Peavey bass amps don't suck; I'll tell you to go plug into an Eden or something. And for the price, Hartke will blow Peavey out of the water once you get something above the 3000 model. It sucks because it NEEDS to do two ohm loads, just because it CAN do two ohm loads doesnt mean its powerful, it just means you need to have it run at 2 ohms for maximum performance, and most amps wont be able to do the amount of cabs you're using with the peavey at their impedance ratings, so you've got a wasted cab practically if you have multiple cabs if you decide to get a better amp.
  6. Ignore all of the previous posts, they didn't bother going to the Peavey web site and reading the manual on your amp.

    Your amp has, basically, two power amps. They can be run bi-amped, meaning the amp has an internal crossover that diverts the highs to one channel and the lows to the other. Or you can run in full range mode, meaning the crossover is bypassed and both amps get the exact same signal. Regardless of whether the amp is running bi-amped or in full range, each amp is capable of running a 4 ohm load. So you can plug a 4 ohm cab into the high section, and a 4 ohm cab into the low section, then decide if you like the sound better with the bi-amp switch in or out. What would NOT be recommended: don't plug both 4 ohm cabs into the same section--both into the low section, for example. The Parallel writing by the jacks means that the ostwo jacks are connected in parallel, so if you plug two 4 ohm cabs into those two jacks, you'll wind up with an effective load of 2 ohms which is not recommended for this amp. Although you could plug two 8 ohm cabs into those two plugs, then the effective load is 4 ohms.

    With two 4 ohm cabs plugged in (one into the High and one into the Low) the amp will put out 200 watts into each cab (for a total of 400 watts). If you plug one cab in, that cab will still get 200 watts, because each section is independent, but the other amp sits there idle. So run two cabs, and enjoy a total of 400 watts.

    Also ignore the BS about the 2 ohm power. My ancient Peavey Series 400 can run into a 2 ohm load, but it still has plenty of oomph into 4 ohms, in fact the difference in power is relatively minor. And I have a Hartke 5000, it can't run into a 2 ohm load.
  7. ESP-LTD


    Sep 9, 2001
    After saving my post I discovered NashvilleBill covered much of it; excellent reading. I would concur about the 2 ohm load issue; any amp puts out different power into different loads, but not every manufacturer makes a head sturdy enough to push a 2 ohm load; it's a feature, not a liability.

    Parallel is referring to how the speakers are wired. Every cabinet I have seen is wired in parallel (as are the output jacks of just about every amp I have seen). Even when you "daisy chain" speakers together, they are most likely wired in parallel. If you were to look at the terminals on the speaker and the jack on the amp it would look something like:

    + --------- + --------- +
    amp speaker1 speaker2
    - --------- - ---------- -

    where series would be more like:

    amp + ----- + speaker1 - --_-- + speaker2 - ---- - amp

    I don't understand what you mean. If you are referring to a cab with 2 speakers and a crossover, normally both speakers are the same impedance (like 4 ohms) and the complete load is 4 ohms because the amp only "sees" one speaker at a time because the crossover handles that.

    The "better sound" really has little to do with impedance of the drivers.

    The "most powerful speaker" could mean many things- loudest, highest power handling before it catches fire, biggest in diameter ... . Generally, most powerful is not a selection criteria for speakers.
    The manual is available at: http://www.peavey.com/media/pdf/manuals/80300567.pdf

    Better is not a simple decision. Biamp allows you to save money by using the crossover in your amp instead of a passive one in a speaker cabinet; I'd call that a big plus (maybe saves $50 per cab) but you have to wire your cabinets to allow that.

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