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4 ohms amp 8 ohms speaker

Discussion in 'Amps and Cabs [BG]' started by fenderaholic, Jun 26, 2005.


  1. fenderaholic

    fenderaholic

    May 25, 2005
    Burbank ca
    will this work. this is not a head and cab this is a combo amp that i plan to replace the internal speaker. will i lose lots of volume or tone maybe cook the amp. plz give me some input.

    eric
     
  2. ESP-LTD

    ESP-LTD

    Sep 9, 2001
    Idaho
    OK, a combo with an 8 ohm speaker, and an amplifier capable of driving a 4 ohm load.

    First, make sure it's an 8 ohm speaker in it; it might be and it might not; Ampeg B100's have a 4 ohm speaker and I imagine others do as well.

    You will NOT cook the amp driving an 8 ohm speaker with an amp capable of a 4 ohm load.

    Any speaker other than the original will certainly have a different tone and volume. Some you might like, and some you might not; depends on how big the cabinet is internally and how it is tuned.

    The SEARCH feature will reveal a lot of this.
     
  3. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Chicago
    Like ESP-LTD said...

    There are so many variables involved when you change drivers that without knowing a lot of information (which drivers are involved, the size of the cabinet, tuning, etc.) it's not as easy as saying :hyper: or :scowl: .

    If the new driver is much more efficient, the overall combination could actually be louder.

    Why do you want to change the speaker to begin with?
     
  4. Lowtonejoe

    Lowtonejoe Supporting Member

    Jul 3, 2004
    Richland, WA
    Yes, it will work. And if you don't already have a 'speaker out' jack you can install one and use an 8ohm extension cab with your combo!

    If your current speaker is 8 ohm, the power going into the 8ohm replacement will be the same. If your current speaker is a 4ohm then you will lose somewhere around 1/3 to 1/2 your available power. Yes, you will lose some volume in this case.

    Speaker sensitivity comes into play also. If you have a speaker with 97db sensitivity and replace it with one that has 103db sensitivity (and both were the same impedance) the new speaker will be louder.

    Tone should not be a huge factor as long as you are using a bass instrument speaker as opposed to a subwoofer. But...there are exceptions. This will require some thought on your part.

    You will not cook the amp by using either a 4 or 8ohm speaker as long as the amp can go down to 4ohms. But if you install a 4 ohm speaker and then try to add an extension speaker you will dip under your minimum impedance and possibly fry your amp. But you can put in an 8ohm speaker and use an 8ohm extention cab. (Like I said before.)

    :D

    Joe.