Amp to cabinet question

Discussion in 'Amps and Cabs [BG]' started by HardRockBassMan, Feb 21, 2002.

  1. I'm using a Carvin DCM1000 power amp that provides 1000 watts bridged to 4 ohms. I'm connecting it to an Ampeg 4x10 and 1x18 (both 8 ohm cabinets). I'm running them in series, maybe not getting maximum efficiency, but I'm really not sure (any help is appreciated on that one as well).

    Anyway, I get a very weak sound. Like there's no (pardon the term) "balls" behind it. Does this make sense? Could the speakers be out of phase? If so, how do I tell?

    I'm kinda lost. I'm using an Ampeg B-2R head. When I use it by itself the 350 watts it pumps out sounds tons better than what I'm getting with the Carvin. I realize I'm not going to get 3 times the volume, but I shouldn't see degraded tone.

    Any help is appreciated.....Thanks.

    Chris Marye
  2. Acepiloto


    Aug 25, 2000
    Are you running any sort of Pre-amp into the Power amp???

    That may be your problem, your bass's pickups aren't strong enough to trigger your power amp's full output. If you run your B2's preamp out (or Effects send) into the Carvin, then you should get all the "balls" you want out of it.
  3. You da man!

    You replied to the other thread I put in this forum. You're very helpful.

    That's exactly what I'm doing. There's a "Pre-amp out" jack on the back of my B-2. I'm going out of that and into the Carvin. Relating to my other thread, I then go out of the Carvin, in stereo to my cabinets. That's why I asked if bridging mode would be better.
  4. Matthias


    May 30, 2000
    Vienna, Austria
    Are you sure? You would need a special cable to do that. If you just hook up one cab to the other with a regular speaker cable the cabs are still wired parallel (total impedance: 4 Ohms)

    If the Carvin puts out 1000W@4Ohms bridged I suppose it puts out 200W@8Ohms per side in stereo mode. This is about the same as the 350W from your Ampeg - each cab will see 200W from the Carvin resp. 175W from the Ampeg.
    By running the Carvin in bridged mode each cab would see 500W instead of 200W - this should make a difference.
    Don't know how 'safe' the Carvin runs in bridged mode though.

  5. Ok........It appears as though I'm talking out of my a$$. Sorry fellas!

    I'll do this-

    Put the Carvin in bridged mode and plug the 4x10 in. I will then go back out of the 4x10 and into the 1x18. If I'm right, after my chastising for not being born with this knowledge, both cabinets should be fed 500 watts from the amp. Correct?
  6. Richard Lindsey

    Richard Lindsey

    Mar 25, 2000
    Metro NYC
    Nothing to be sorry for. I believe you've got it!
  7. Good!!

    Thank you Richard. Thank you all!