Tech question please

Discussion in 'Amps and Cabs [BG]' started by p12bassnut, Jun 28, 2020.

  1. p12bassnut

    p12bassnut Supporting Member

    Aug 27, 2009
    Can you tell if this amp has a class AB or class D power section based on this picture ?
    Inquiry to manufacturer yields no results as of yet.
  2. nilebodgers


    Nov 25, 2017
    I’d guess AB judging by the emitter/source wirewounds and the lack of obvious output filter chokes. Markbass LM?
    fdeck likes this.
  3. p12bassnut

    p12bassnut Supporting Member

    Aug 27, 2009
    Yes LMIII
    Just pulled the top to find out because I was told Markbass changed from AB to a class D in 2013 and this is an early 2013 model. Nothing wrong with the amp, works perfectly.
  4. beans-on-toast


    Aug 7, 2008
    I see a transformer date code of 25/12, 25th week of 2012. Another is 20/12. There is a chance that your amp was manufactured in 2012.
  5. dbase

    dbase Gold Supporting Member

    Jan 3, 2008
    South Jersey, USA..
    I would say Class D since I don't see a big heavy transformer plus the fact it weighs only 6 lbs. I'll stop there since that's as far as my knowledge goes. ;)
  6. BassmanPaul

    BassmanPaul Inactive

    It has a Switch Mode Power Supply - that's the stuff on the right of the chassis. One of those can supply a Class D output stage OR a Class AB. With my lack of Class D tinkering I would say the beast is Class AB.