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2X15" speaker replacement question

Discussion in 'Amps and Cabs [BG]' started by bazzanderson, Aug 18, 2005.


  1. bazzanderson

    bazzanderson

    Oct 7, 2002
    Austin, TX
    2X15” speaker replacement question.

    I’m most likely going to be replacing my peavey black widows….they are starting to sound really bad due to running a low wattage amp at high volumes through them.

    I’m probably going to replace them with two 8ohm Eminence Delta 15LFs. Since these are 8ohm speakers would I wire the hot from one speaker to the ground of the other then wire the remaining hot and ground to the jack to achieve a 4ohm load? I’ve never done this before so your advice is greatly needed. The whole point of this of course is to achieve a 4ohm load with two 8ohm speakers.

    Thx,
    -Bazz-
     
  2. RobertUI

    RobertUI Thumper Supporting Member

    Apr 7, 2005
    Herndon, VA - NoVa
  3. Jarno

    Jarno

    Jan 27, 2005
    Hello Bazz,

    I used RCF L15/554K 's in my cabinet, these are very very loud (efficiency 102dB/ 1W/ 1m). And as these are PA speakers I feel that they are a bit more articulate than instrument speakers. But if you're looking for a "warmer" sound, look elsewhere (although I think the Black Widows are also quite the "high efficiency - higher Fs" type).

    Regards,

    Jarno.
     
  4. Petebass

    Petebass

    Dec 22, 2002
    QLD Australia
    2 things. Firstly, the wiring you described is refered to as "series" wiring, will achieve a 16 ohm nominal impedance from 2 x 8 ohm speakers.

    To get to 4 ohms, you need a "parallel" connection. This can be done 2 ways. To make you feel more comfortable, I keep using "Hot and ground" instead of the more traditional "positive and negative" terminology:-

    1) wire the hot from one speaker to the hot of the other, then wire the ground from one speaker to the ground of the other speaker. The result is a 4ohm load.

    2) Run 2 wires the hot from the jack, one going to each hot terminal of each speaker. Then run 2 wires the ground from the jack, one going to each ground terminal of the speaker. Again we get a 4 ohm load.

    Now to the issue of Delta 15lf's. The Thiele small paramaters of those speakers dictace a very large cabinet size. For optimal performance, they require upwards of 10cu.ft per speaker. That's an enormous cabinet and I doubt your existing cab is that big?

    I suggest you post the cab's dimensions and we find a speaker tha suits it better.