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opinions on what to do.

Discussion in 'Amps and Cabs [BG]' started by outofthere, Oct 18, 2000.


  1. outofthere

    outofthere

    Oct 18, 2000
    I picked up a peavey cs-400 (not cs-400x) which has been lab tested to clip at 2x266w RMS at 4 ohms per side. I'm currently running just one side of the amp into a 6 cubic feet ported at 35hz isobarically loaded 2x15 cab built by myself.

    I'm reasonably satisfied at the sound qual but I'm wondering what to do about loudness factor. Not that it isn't damn loud for my bedroom when I play normal music through it (obviously more brutally crossed over) but my original and current plan is to get another two of these 15's and cram them into about 6-8 cubic feet (bearing in mind that each isopair only needs 3 cubic ft) so I could maximise both sides of the amp.

    Is this a wise idea or would I benefit from just getting new, more costly drivers and less of them in terms of loudness (assuming that the amp was being drove to basically its limits). I play a 5 string so I do need good low response which I get from the woofers.


    On a side note the subs are 94db/w sensitivity and have 120w RMS power handling per speaker.

     
  2. CS

    CS

    Dec 11, 1999
    UK
    Your post title does not reveal the technical nature of text inside. You have had two hits and I dont have a clue.

    Try e-mailing Joris or repost with a different title.
    THere is someone else here who made a monster cab with 8x8s and 2 15s in it. I THINK its Bob Golier (sp)
    I hope you get your answer.
     
  3. brewer9

    brewer9

    Jul 5, 2000
    Oh man, i read your post several times now and have no clue what you're talking about. Please state in simple form what's wrong. Is it that you arent getting volume from your rig? thats my best shot at it.

    Hint: lose the tech-talk.
     
  4. mikemulcahy

    mikemulcahy

    Jun 13, 2000
    The Abyss
    CALLING JORIS........COME IN JORIS
     
  5. ihixulu

    ihixulu Supporting Member

    Mar 31, 2000
    getting warmer
    At sensitivity of 94db you simply aren't going to get much in terms of efficiency. If you are going to be pushing 200 watts or so you probably want to find drivers that have an SPL of 98 and up to get more volume.
     
  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
    You'd be better off just getting back to the basics ... an Eden WT-800 and two D-410XLTs. Problem solved.
     
  7. outofthere

    outofthere

    Oct 18, 2000
    My question is mainly related to whether drivers with a 94db sensitivity are sufficient.. as in what the norm is with pa drivers and whatnot. For a 15 inch sub 94 db is pretty good but would I benefit from going to say.. as a test case one or two peavy black widow's instead of 4 of these drivers.

    I'm trying to find out whether this configuration of about 500 watts going into 4x15 is going to cut it in a live setting (I know the venue size is important but I can't really be sure what size we're talking about yet).

    Sorry about the subject name of the thread, I wasn't really paying attention to what I was doing.

    Brewer: If I lose the techtalk I lose the specifics of my question.


     
  8. ihixulu

    ihixulu Supporting Member

    Mar 31, 2000
    getting warmer
    Go to Eden's site (www.eden-electronics.com) or SWR's site (www.swraudio.com) and check out the specs on their 2x15 cabs, you'll see that they tend to have a higher SPL. In fact I think 94 is pretty low for musical instrument applications, although ACME's efficiency go lower. Whether it's sufficient depends on how much power your amp puts out and in my opinion you need way more power than what you're pumping now.

    I have to agree with Munjibunga, there are simpler solutions out there for what (I'm guessing) you're trying to do.
     
  9. There are a few variables we need to know, the ohms of each speaker, and the minimum load the amp can drive. An isobaric setup in which the two speakers are coupled together either face to face or in a small chamber (doggie style) results in a decrease of 3db in sensitivity over one speaker giving you 91 db. It also halves the size of the cabinet required. You could drive each speaker separately from the two power amps(paying attention to phase) and gain a little output. If you are sucessfully driving both speakers from one amp than either the speakers are 8 ohm or the amp can drive 2 ohms.
    Limited to 120 watts per speaker, you are pretty much at the limit and doubling the number of speakers seems to be the only practical way to increase output. PA and instrument speakers aren't really designed to go to 31 hz. I'd think that with over 500 watts avaliable, even with 91db of sensitivity, you could make a lot of noise