Discussion in 'Amps and Cabs [BG]' started by GrandMarkie, Mar 10, 2004.

  1. GrandMarkie


    Feb 7, 2004
    Waltham, MA
    Just picked myself up an SVT-4 along with an SVT 8x10. I've been reading alot about 4 and 8 ohms along with bridging, mono/stereo etc. What are my options for hooking up my cab and what are the differences between my options? Sorry for being such a noob...
  2. Well, with one cab methinks your options are limited to

    1) running bridged mode into your cab
    2) running one channel of your amp into your cab.

    Now if you get another cabinet you have more options. depending on the impedance of your cabinets, you could run the amp in bridged mode and the cabinets in parallel if they're 8 ohms each. Two of the same impedance cabinets in parallel halves the impedance that the amp sees. According to the Ampeg web site that amp won't take 2 ohm load in bridged mode. Or you could run them in stereo. I've never had a stereo amp before, but folks say that in bridged mode there seems to be more headroom that running the two channels independently.

    Generally speaking most amps running bridged want twice the impedance of a single channel. It has to do with how much current the amp can deliver, and how the signal is split between the two channels.

    BTW, noobs seem to be pretty welcome here. I seldom see you guys trashed for not knowing anything. That's what Talkbass is all about - sharing what we know :)
  3. seanm

    seanm I'd kill for a Nobel Peace Prize! Supporting Member

    Feb 19, 2004
    Ottawa, Canada
    I think your SVT 8x10 is actually two 4 ohm 4x10 cabs with two seperate connections in one box. If this is true, you have to run in stereo. Two 4 ohm cabs in parrallel is 2 ohms, which is below the minimum impedence for the head in bridged mode.

    Without getting into to much technical detail, a stereo amp bridged produces more power at a given impedence that in stereo but can only go down to half the impedence.
  4. Jerrold Tiers

    Jerrold Tiers

    Nov 14, 2003
    St Louis
    All the current 8-10 cabinets and the past ones I can think of are either set up as a single straight 4 ohm, or in some cases 2 x 8 ohm, which again gives 4 ohms as a single load.

    I can't think of any 8-10 that were shipped set up as a 2 ohm single load or 2 x 4 ohm. The SVT 2 ohm tap is for running two cabs.

    If someone re-wired it or replaced speakers, of course there could be almost anything in it, so you might just check it unless you know its history....... Look on the cab, it should say what impedance it is if the label is still on it. And modifications usually leave traces...

    A 4 ohm load is OK for bridged mono on the 4Pro, so enjoy the 1200 watts .......
  5. GrandMarkie


    Feb 7, 2004
    Waltham, MA
    Thanks guys. There aren't seperate inputs for each 4x10...only 1. So as I understand it, I can run the mono bridged which will supply the 1200 full watts. Or I can run my cab into 1 of the 2 internal amps (1 for low frequencies or 1 for high frequencies) but this would be pointless since it uses half the power. Am I correct? I assume if I bought a 2x15, thats when this would come in handy.