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Question on Speaker Quality/Brand Quality

Discussion in 'Amps and Cabs [BG]' started by TheChariot, Jul 25, 2004.

  1. TheChariot


    Jul 6, 2004
    Boston, MA
    Alrighty... I plead ignorance on this one. figured I'd just ask a question on here and have one of the many brains around here answer it. :smug:

    Ok... so I've been searching for my next possible upgrade (power-wise), and I decided it should probably involve purchasing one cab that I can run my power amp bridged into. I checked out some brands, and I got to Epifani.

    I checked out the 6x10 cab, and it stated that the RMS is 800W. However, I noted that the peak was a lot higher than I normally see it in comparision to other cabs.... I think like 2400W. Until that point, I was under the impression that a cabinets Peak was usually at or around double the RMS. Does this fact sort of change with higher priced speaker cabinets? It even recommended putting about 1000W to 1600W into it. I'd be using 1400W Bridged.

    Is the lower RMS misleading? Is the higher Peak misleading? Or am I talking about things that are to insane that my head would explode if I'd even began to know what I was talking about?! :eyebrow:

    Thanks for reading :D

    PS: I <3 Family Guy
  2. JMX

    JMX Vorsprung durch Technik

    Sep 4, 2000
    Cologne, Germany
    RMS is probably the most reliable, even though it also differs from manufacturer to manufacturer.
    Peak power is much more unreliable and not as useful as a reference.

    That cab can take enough power IMO.
  3. Lockout


    Dec 24, 2002
    Peak power really doesn't mean anything.

    I wouldn't worry about putting too much power into your cab, because your amp generally will be putting out much less than 1400W in normal use. As long as you don't clip the amp, I think you should be fine.
  4. Yossarian


    Jun 24, 2004
    If I were you I would just email the company and ask. Or look at a FAQ or something on the website. I spent forever trying to figure out what to do with my Peavey rig and trying to understand RMS vs. program vs. peak, and then I looked on the FAQ at the Peavey site and it plainly said "the rule of thumb is you want no less than the RMS power and no more than the program." and that was all I needed.

    It sort of implied that just only applied to their cabs. Seeing as many dont even mention program power. There should be some scientific standard for this. crazy amp folk.
  5. Hollow Man

    Hollow Man Supporting Member

    Apr 28, 2003
    Springfield, VA
    Never go higher than the peak rating. That's the big rule. Everything else is secondary. You can go below the RMS rating, but your speakers won't be performing up to their full capability. This doesn't hurt anything; it just means the speakers aren't showing their full potential, either in volume or tone.

    RMS (or root mean square) basically tells you what the peak average signal can be. But since you don't produce constant waveforms as you play, you can safely exceed the RMS rating.
  6. TheChariot


    Jul 6, 2004
    Boston, MA
    Thanks for the input.

    I did my research wrong anyways :spit: Turns out the cab with the 800RMS is the 2x12... which I dont think I want. the 6x10 has an RMS of 1500W actually... and that's more than I'd need. I'm now considering dumping my heavy a$$ BXT cabs for $1000 if I'm lucky, and maybe picking up an Ultralight 610. Come to think of it... even the NYC version of the 610 would be more transportable for me than the BXT's, because it's got the tilt-back wheels.

    ::ponder:: :eyebrow:
  7. andruca


    Mar 31, 2004
    Madrid (Spain)
    Let's review some definitions:

    It's the power that the amp can give continuously from it's power stage. If applied to a cabinet or a speaker, it's the power that it can hold up with continuously also.

    Normally twice the RMS power, it's the power that an amp can deliver during an input peak (but not hold up continuously). Speaker-wise, it's the power it can stand for an instant without blowing. For example, the attack of a note (the pluck "moment"), that is a very brief lapse in which power is greater than during the sustain/release of the note (the second "moment" of a bass note).

    Both RMS and PEAK are measured in a wide frequency range.

    There is also another measure that, although not used for instrument amplification (more familiar with home audio) is very spread these days, the PMPO (peak music power output -not "peak"-) measure (about 20 times the RMS power). But I don't know how this measure can be represented phisically (not being RMS nor the old peak representation, what is it?). Maybe it's obtained measuring the peak power but in a very narrow frequency range (the range where the speaker can hold up more power) so they can obtain these very high power values. My main suspicion is that it's just an "eye catching" commercial purpose measure, but, hey, my old Peavey TKO-80 (75W RMS) is 1500W then!!!! WOW!!!

  8. Selta


    Feb 6, 2002
    Pacific Northwet
    Total fanboi of: Fractal Audio, AudiKinesis Cabs, Dingwall basses
    There is...it's in every college physics book too. :)
  9. Bob Lee (QSC)

    Bob Lee (QSC) In case you missed it, I work for QSC Audio! Gold Supporting Member Commercial User

    Jul 3, 2001
    Costa Mesa, Calif.
    Technical Communications Developer, QSC Audio
    Power amps do not use "program" power; that is a loudspeaker term. Reputable amp companies do not use "peak" or "music" power, either.

    Joris's amp FAQ page has some good and accurate definitions of power terminology.
  10. TheChariot


    Jul 6, 2004
    Boston, MA
    Oh, I get it and all, for the most part...

    Just... the Epifani cabs have a "peak" that is more than double the RMS. I just found peculiar. But anyways... my question isnt so relevant anymore, now that I looked at the site more accurately.
  11. Yossarian


    Jun 24, 2004
    Hehe I know, I mean like... a standard for how the amp companies show their measurements. I guess that would be more legal than scientific... shhh. Peavey tells me get higher than the RMS, but below the program, then GK tells me NEVER higher than the RMS, and they dont mention program, then talkbass people are like "twice the RMS, do it!" And then I just don't know how to feel, so I quit playing bass and take up harmonica. :(