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Eminence Query

Discussion in 'Amps and Cabs [BG]' started by bass-shy, Sep 10, 2005.


  1. bass-shy

    bass-shy

    Jan 11, 2005
    Florida
    I've been thinking about building a cab that contains a 15" and two 8" drivers. While researching speaker specs, I came across the Eminence Kappa 15C and Alpha 8MR drivers. Does anyone have any experience with these models? Are they any good? The power handling is in the ballpark for my amp and the sensitivity ratings are 103db and 102db, respectively. They seem great on paper.......what about in real life?
     
  2. I don't have experience with those but I do with the Kappa Pro 15lf and the Alpha 8 drivers. They sound great together IMO.
     
  3. Petebass

    Petebass

    Dec 22, 2002
    QLD Australia
    On paper, you're looking at a cab for the 15 which is about 89litres (3.14cu.ft) which isn't too bad for a 15, tuned to 31Hz. Of course the down side of high efficiency cabs is thay don't always go all that low. With this speaker, you're looking at a -3dB point of 75Hz.

    However it does look to be good right up to 3K. I'm thinking you might not even need 2 x 8's. You should be able to get a strong midrange presence with just 1 x 8, given that it is going to overlap with the 15 up to 3K. Whether of not that's a bad thing is entirely up to you.

    As a comparison, Mizikman's Kappa Pro 15Lf, is not quite as efficient at 100dB, but produces more lows. Cab size is lightly smaller at 82 litres (2.19 cu.ft), which when tuned to 46Hz, gives a -3dB point of 55Hz. To me this speakers is better suited for bass than the Kappa 15c.

    The LF is only good to 1.5K but this is a non-issue since you're planning to use an Alpha 8MR for mids. Again I'd be leaning towards using only one of them.
     
  4. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    Agree with Pete 100% on that one. I'd cross to the A8MR at 800Hz.
     
  5. Doug Parent

    Doug Parent Supporting Member

    May 31, 2004
    San Diego, Ca.
    Dealer Nordstrand Pickups.
    Interesting project, reminds me of the Carvin Cyclops which is basically the same. 1)15 2)8's and tweeter. all using Eminence drivers. That cabinet is punchy but had very little lowend.
    The old JBL Caberet series 4528? was a K-145-15 and a 8"/tweeter combo. Pretty heavy, but the JBL is a good sounding unit.

    good luck with your project.
     
  6. ESP-LTD

    ESP-LTD

    Sep 9, 2001
    Idaho
    The Peavey 1516 is a similar box; 4 ohm 15" BW on the bottom, ported, with a pair of 8" 8 ohm Eminence drivers on top (they seemed like low end guitar drivers) in a sealed space. Their XO was 250hz I believe, while the 1810 was 125hz I believe; those seemed pretty low to me since a BW makes a lot of mids.
     
  7. If you're going to cross over these drivers you would have to choose wisely. If you stick with the Eminence line you should go with 1 driver for each frequency band so the volume of the cab would stay more even across the frequency spectrum.

    My current project involves running all drives full range. I'm using the Kappa pro 15lf in a vented enclosure approx 3.6 cu. ft. tuned to 50 hz. I am currently using a prototype vertical array 1.8 cu. ft. sealed enclosure for 4 Alpha 8's (not the MR). I'm not trying to produce a flat frequency response, I'm going for good volume, smooth underlying fundimentals, and punchy in your face mids and harmonics.
     
  8. bass-shy

    bass-shy

    Jan 11, 2005
    Florida
    Thanks for all of your replies guys, I am very excited about this project. You all seem to have a lot of experience and knowledge about these matters. Another thing I have considered is just replacing the speakers in my Carvin RL6815 combo. The stock speakers only produce 95db at one watt but are quite punchy, I get plenty of lows out of them, and I like the way they sound, but my goal is to substantially increase volume. The head in this combo is an R600, which can be run full range or bi-amped with a variable X-over from 200hz to 2kHz. Do you think this is worth doing, or should I just build the separate cab to use with the R600? I really love this head. It does everything well and I don't want to replace it. Thanks for your help.
     
  9. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    They're Eminence.
     
  10. bass-shy

    bass-shy

    Jan 11, 2005
    Florida
    I understand that they're Eminence, they're just not as efficient as the Kappa 15 and Alpha 8MR's. The way I understand it, the easiest and most efficient way to increase output is to either add speakers, or use more efficient ones. I like the idea of having everything in one box, so I don't want to add another cab. Also, I understand that I would have to multiply the power going into the cab by ten to get a 3db increase. This is way too wasteful. By just replacing the stock Eminence speakers, which produce 95db at one watt, with the Kappa and Alpha speakers, which produce 103db and 102db, respectively, I should get a significant increase in output. The combined cost of new speakers is around $200.00 US. This is way more affordable than anything else I can do to get my desired result. I am just curious to know if these particular speakers will be a good choice, or if there are others I should consider.
     
  11. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    Not necessarily. The ratings of the Kappa 15and A8MR are not broadband. The Kappa 15, for instance, only reaches 103dB sensitivity above 1.2kHz; through most of its range it actually runs around 98dB. It also has an xmax of only 1.6mm, making it's usefulness as a bass driver marginal at best. In order to make a useful comparison between drivers you must consider at least a half dozen specs, not just one or two.
     
  12. bass-shy

    bass-shy

    Jan 11, 2005
    Florida
    Are there other speakers I should be considering? I really don't know a whole lot about this sort of thing. I am trying to treat it as a learning experience. What other specs should I be concerned with? Thanks for your help.
     
  13. Petebass

    Petebass

    Dec 22, 2002
    QLD Australia
    These questions are loaded far more than you realise. I could answer them but I don't feel like writing a text book.

    Perhaps you should start by looking at

    http://www.epanorama.net/links/audiospeakers.html

    There's lots of info there about loudspeaker design and Thiele Smll paramaters, most of it and is in plain English.

    If after reading through that, you want to learn more, grab a copy of "The Loudspeaker Desing Cookbook" by Vance Dickason.
     
  14. bass-shy

    bass-shy

    Jan 11, 2005
    Florida
    Thanks for the link. I'll educate myself and hopefully, can reach a solution. Thanks everyone.