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Amp load question #2

Discussion in 'Amps and Cabs [BG]' started by fourstringbliss, Apr 13, 2005.


  1. My amp will put out 300w at 4 ohms. What would be the volume difference between a 4 ohm 212 cab and an 8 ohm 212 cab on this amp?
     
  2. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    About 1.5 dB; i.e. hardly anything.

    Alex
     
  3. So, if I got an 8 ohm Avatar 212 it would only be a little quieter than the 4 ohm Avatar 212? That would be really convenient for adding an 8 ohm 212 to later for the full 300w.
     
  4. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    Exactly.

    Alex
     
  5. Sweet! I'm pretty sure that a 212 will be enough for me, but if I want to add another cab I don't want to have to sell and buy different cabs to make the right amp load. Thanks again!
     
  6. Thought I read somewhere that a 4 ohm version of a driver was same volume as the 8 ohm version of the same driver.

    Sounded stupid, the 4 ohm gets more power, but if you think of "why" its 4 ohms vs 8 ohms it makes more sense. The reason the driver is 4 vs 8 ohms? Less windings in the voice coil. Twice the windings in the 8 ohm voice coil would double the mag field, but cuts the current in half, so its about a wash.

    So if that is true, there would be no loss of volume for the 8 ohm 212. If its not true, whoever said it'd be about 1.5 dB quieter is about right. Not noticeable, and with an 8 ohm cab you have the option of adding another 8 ohm cab.

    Randy
     
  7. 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
    It depends on the sensitivity of the cabs.
     
  8. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    It does?

    Alex
     
  9. I'm wanting to get an Avatar 212, and if an 8 ohm cab will only be a little quieter than the 4 ohm cab, I'll get the 8 ohm and add an 8 ohm 210 or 115 later.
     
  10. Highpipes just clued me into this great item: Speakermate. This would allow me to get the 4 ohm 212 and add a 4 ohm 210 later while still only loading my amp down with 4 ohms!
     
  11. Tim__x

    Tim__x

    Aug 13, 2002
    Alberta, Canada
    Hmm, I wouldn't trust that, it doesn't appear large enough to have a transformer in it, it's probably extremely lossy. Get the 8 ohm cab.
     
  12. It would have to have a transformer in it? What would be the real sound difference between the 8 and the 4 ohm cab?
     
  13. Eric Moesle

    Eric Moesle Supporting Member

    Sep 21, 2001
    Columbus OH
    There was a detailed thread on the Speakermate device some time ago. In a nutshell, the Speakermate is ONLY a device which lets you avoid having to use different cables when changing between series and parallel scenarios with different cab combinations. It does NOT have a transformer or otherwise let you perform magic or circumvent Ohm's Law.
     
  14. Tim__x

    Tim__x

    Aug 13, 2002
    Alberta, Canada
    Now that I've looked at the connection pics that's clear.
    The "equalized power" claim seems phoney, look at the fourth picture, clearly it parallels the two eight ohm cabs and puts that in series with the four ohm cab, but that in no way provides equal power to each cab.