1. Welcome to TalkBass 2014! If you're new here, we just went through a major site upgrade. Please post all concerns and bugs to the Forum Usage Issues forum. We will be monitoring that forum. Thank you for all of your feedback.

    The TalkBass iphone/android app is NOT WORKING currently. We're working on it. Tapatalk IS working, so if you need to use an app, use Tapatalk. Try using your browser though - TalkBass is now 100% responsive to your phone/tablet screen size ;)

    Please read the TalkBass 2014 FAQ for lots of great info on the new software.

GK MBFusion 800 Tube Rolling

Discussion in 'Amps [BG]' started by 2string1, Nov 27, 2013.

  1. 2string1

    2string1 Supporting Member

    Joined:
    Apr 1, 2013
    Likes Received:
    0
    Has anyone done any tube rolling in the Fusion 800. What where your results. I called GK,they didn't seem to know which tube did what...
  2. JonnyAngle

    JonnyAngle Supporting Member

    Joined:
    Nov 24, 2008
    Likes Received:
    0
    I don't own one or have any experience with them, but here's what my memory produced from what I think I remember reading.

    You have to move a circuit board to access the tubes any your warranty will be void afterwards.

    I'm sure GK knows exactly what tube does what, but they're hoping you'll forget about it from their non-response and move on. I'm sure there are a lot of people "who know what they're doing," and mess things up. They will have a response like, "GK told me if I put tube X in my MB800 X will happen. I did exactly what they said and now my amp won't work."
  3. 2string1

    2string1 Supporting Member

    Joined:
    Apr 1, 2013
    Likes Received:
    0
    No...the tubes are right under the cover very easy to get at. I did end up getting and email, this is what they said.

    "OK, I spoke with the engineer and he supplied the following information regarding what tubes drive which stages. The tubes are placed in the circuit left to right as you look at the front of the amp. Each tube has multiple stages stages so each tube may effect multiple functions".

    V1 – Input driver and Contour
    V2- High Mid
    V3- Low Mid/ Bass and Treble

Share This Page