Ampeg SVT-6 Pro Run W/O Load?

Discussion in 'Amps and Cabs [BG]' started by KoolCharisma, Dec 18, 2016.

  1. My SVT-6 Pro has 4 tubes in the power section, but it's also solid state. Do I need to load the amp to play or can I use it for DI purposes without a cab? Ampeg addressed the issue in their faq, but unfortunately didn't cover the 6 Pro.

    "Any Ampeg amplifier with a solid state output (SVT-4PRO, SVT-3PRO, SVT-350H, B-5,4, and 3R) can be used for recording purposes using only the line output to record and without speakers attached to the speaker jacks. The amp must have a speaker load if the amp has a tube output section (SVT-CL, SVT-2PRO, and V-4B), not doing so can result in extensive damage to the amplifier."
  2. LiquidMidnight


    Dec 25, 2000
    The SVT-6 has tubes in the preamp, not the power amp. As long as the amp doesn't have an output transformer, you should be good.
    DiabolusInMusic likes this.
  3. JimmyM

    JimmyM Supporting Member

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    Yep, you're good with the 6 Pro, too.
    DiabolusInMusic likes this.
  4. There are two tubes in the preamp, 4 in the power section, but the transformer is the big round Class D kind for SS DC conversion. That's why I'm leary, because it's really a different animal. All other Hybrids I've seen have tubes exclusively in preamp section, which doesn't require load.

    Ampeg says:
    "Preamp: Tubes (2 x 12AX7)
    Driver Tubes: 2 x 12AU7, 2 x 12AX7
    Power Amp: Solid State "

    So 4 tubes are "Drivers", whatever that means. Is there a particular transformer, component, or other marker inside that would indicate the necessity of load?

    Jim, I know you know your ampegs, I'm just curious why you're confident I can run without load. I've invested a lot of time in rebuilding the amp, so don't want to torch it.
  5. JimmyM

    JimmyM Supporting Member

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    Driver tubes can't be used for generating power...they are used for driving the SS power section, whatever that means :D The SVT 3 Pro also has driver tubes, and it can safely be used without a cab. And there is no output transformer in the 6 Pro, and that is your main concern when using an amp without a cab, as an output transformer without a speaker load on it sees what's called "infinite ohms" and goes into panic mode and burns up if you let it go too long. Tube amps almost always have an output transformer, and SS and hybrid amps almost always do not. Your 6 Pro does not, so it's safe to use without a cab.

    I would not steer you wrong on that. If I thought there was a possibility that it was unsafe to use without a cab, I'd tell you not to do it. You are in the clear.
    KoolCharisma and LiquidMidnight like this.
  6. DiabolusInMusic

    DiabolusInMusic Functionless Art is Merely Tolerated Vandalism

    The SVT-6Pro is a solid state amp, it can most definitely be run without a load. I have done it.
  7. Awesome. Just the answer I was looking for.