what makes GK amps "quick"?

Discussion in 'Amps and Cabs [BG]' started by MacheteJames, Oct 7, 2003.

  1. I'm thinking of picking up a used GK400RB as a spare head. You always hear about how GK amps are "quick", meaning that the sound just kind of jumps out of the speakers faster than say, an Ampeg SVT or something. Why is this? There has to be some kind of technical explanation. I heard something about GK using large toroidal transformers, what are these, are these the reason why this is so?


    Aug 13, 2003
    Sulphur LA
    Former GK employee here. GKs have high current capacity which translates into a ton of headroom and that fast response. I don't know any easy way to explain current capacity. Sorry about that.
  3. Thanks Trip, I knew it had to be something like that.
  4. Correct me if I'm wrong here...

    Basically, the power supplies in GK amps are capable of providing a lot more current than the amp can draw under average conditions, so that the rail voltage doesn't sag when the amp is driven hard. This improves the transient response of the amp. Good transient response is interpreted as 'fast' by our ears.
  5. JMX

    JMX Vorsprung durch Technik

    Sep 4, 2000
    Cologne, Germany
    Also, solid state amps are "faster" than tube amps.
  6. I think that's more related to damping factor than anything else. Tube amps have inherently low damping factors because of the output transformer. This tends to give them less LF cone control than SS amps and why tube amps tend to sound their best into sealed boxes...
    Slew rates in tube amps are sufficiently fast enough to be beyond our perception, and are just as fast as those in many SS amps.
  7. JMX

    JMX Vorsprung durch Technik

    Sep 4, 2000
    Cologne, Germany


    Aug 13, 2003
    Sulphur LA
    You are both correct! Good explanation Mark! Hey, JMX I played a Bass Art pre and Bugatti Power amps at Bass Quake for my show. It was godlike!

    "I think that's more related to damping factor than anything else."

    GKs have low damping factor according to Bob Gallien. Love to all!
  9. Actually the 800RB has low damping. The other GK amps have high damping. Not as high as a PA amp, but that's not necessarily good for an instrument amp.
  10. Petebass


    Dec 22, 2002
    QLD Australia
    Correct ME if I'm wrong.....

    Is this why some people think that their 2 ohm capable amps sound better when operating on a 4 ohm load?
  11. Low DF? How low?
  12. Subculture13

    Subculture13 Jamming Econo

    Apr 9, 2003
    Toronto, Ont. Canada
    I have a GK 700RB head that has never been used. I've carried it around as my backup, and never really needed it. It's a great amp, I tried one out in the store when I bought mine, but didn't take the "floor" model when I made my purchase, I took one from the stock room, hence the "never been used" status. I have decided to upgrade my main amp, so I am selling off the 700RB, with the intention of "demoting" my current main amp to backup status. I'm about to go on Ebay with it, if you are interested I'd consider an offer here first, if you wanted it.
  13. One of our engineers is going to measure it this week so I'll let you know what the actual numbers are.
  14. miccheck1516

    miccheck1516 Guest

    Feb 15, 2003
    ive never seen a rep from a company here
    well done to DK
  15. Petebass


    Dec 22, 2002
    QLD Australia
    Hang around, there are quite a few more........'
  16. I'm probably gonna wait till closer to christmas time, but damn.. if I had the $$ on hand I'd take you up on that. Thanx anyways.
  17. IvanMike

    IvanMike Player Characters fear me... Staff Member Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    when comparing a gk to an svt it may have a bit to do with the preamp as well
    for example, demeter makes 2 preamps, one has 2 tubes and the main out is tube driven, the other has one tube and drives the main out with a solid state device - the 2nd one sounds a bit tighter and "quicker" which demeter told me is inherent when comparing tube to ss (at least in the final output stage)

    oh, besides a gk is quicker than an svt cause you can run faster with it