Is my head too weak?

Discussion in 'Amps and Cabs [BG]' started by RicPlaya, Aug 22, 2003.

  1. RicPlaya


    Apr 22, 2003
    The Mitten
    I have a GKRBIII400 head puts out 240w @ 4 ohms. when I run this with my Ampeg HVT 4x10 cab it seems I can always get a muddy, farty sound at high volumes. I have adjusted every knob into every possible configuration and it still does this. The cab is rated for 500w @ 4 ohms, if I upgraded my head would this solve my problem? For example if I went to a GKRB1000, or a Carvin1000 would it clean it up? Or, could I bridge the RB400 to double the output by putting a splitter cable which has two jacks for the two outputs from the head into a single input into the cab without damaging the head?
  2. mikezimmerman

    mikezimmerman Supporting Member

    Apr 29, 2001
    Omaha, Nebraska
    More power might help.

    However, you most certainly cannot "bridge" the RB400. Bridging is for combining two halves of a stereo power amp, so that you can put the output from both halves into a single cabinet--it's not a way to "double the output power" or "get something for nothing". The GK isn't a stereo amp, just an amp with two jacks.

  3. I agree. A head with more power will give you more headroom, especially on a 5-string. But do try it first.

  4. pyrohr


    Aug 28, 2001
    Pakistani compound
    I too had the same head but in a combo form. I had the 400RBIII 1x15 combo, and a RBH 1x15 cab. At low volume it didn't sound bad , at a higher volume it did start to woof and fart. The reason for that is the combo only put out a max of approx 120w's into a 400w cab severly underpowering it. To fix this problem I traded in the 400RBIII combo for a 1001RB 2x10 combo. Now I have the headroom and use of the tweeter amp at my disposal. you might want to go to 5 or 600w head with that bottom to enjoy the cap the right way it was meant to be heard.
  5. IvanMike

    IvanMike TTRPG enthusiast, Happy, Joyous, & Free. Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    it sounds like you are describing the amp "clipping"
    this occurs when you run out of headroom and the amp is no longer able to accurately produce the signal being fed into it
    the bad news is it sounds terrible
    the really bad news is you can easily destroy your speaker by doing this
    belive it or not, more speakers are blown by 200 watt heads than they are by 2000 watt power amps
    if you are running into this problem you should definitely check out other more powerful heads (or preamp/power amp combinations) before you destroy your speakers
  6. RicPlaya


    Apr 22, 2003
    The Mitten
    thanks everyone!!!! I need a new head.
  7. c-ba55

    c-ba55 Supporting Member

    Feb 6, 2001
    San Francisco, CA
    Or, you know--theoretically, you could not play so loud.
  8. RicPlaya


    Apr 22, 2003
    The Mitten

    That would be no fun at all!
  9. KeithPas


    May 16, 2000
    You probably have already gathered this by other posts but do not plug two heads into one cabinet. Believe me, nothing good will come of that. :eek:
  10. wushuguy


    Jan 9, 2002
    Flagstaff, AZ
    It seems that you already have your answer, but I just wanted to chime in. I had a GK400rbIII and 400rbIV. Niether had the had the headroom to get the volume that I wanted. It did the same as yours, farting and all. Now I have an SVP through a QSC power amp, and can get as loud as I'd ever want. Your problem is most definitely the amp clipping.
  11. Something about that...

    My Torque Cab, 4*10, 240Watts, Celestion speakers, has got 2 imput jacks.

    Why 2???? 1 should be sufficient. When I use 2 cables from my amp into both jacks I hear no difference. Both Jacks give me the same sound.
  12. KeithPas


    May 16, 2000
    The two inputs on the back of the cabinet would be for your amp and another speaker. Running two heads into one cabinet can damage the head and the speakers. Email the manufacturer of the amp and cabinet and double check but be careful.
  13. going carvin would be a horrible downgrade... BS it's 1,000 watts... get the 1001RB
  14. Eric Moesle

    Eric Moesle Supporting Member

    Sep 21, 2001
    Columbus OH
    Its there for flexibility, NOT for connecting two cables from your amp to the cab, that will damage your gear.

    Example: One cable from amp to cab1, then a cable out of cab1 to cab2.
  15. RicPlaya


    Apr 22, 2003
    The Mitten
    two words MORE POWER! I'm trading that sucker in and getting gkrb1000 or comperable..