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DB680 owner? I need you to do me a solid.

Discussion in 'Amps and Cabs [BG]' started by jasonbraatz, Aug 18, 2005.


  1. jasonbraatz

    jasonbraatz

    Oct 18, 2000
    Oakland, CA
    My new DB680 hasn't been sounding as good as it is supposed to, so I decided to replace all the tubes. Crack it open and SURPRISE instead of being three 12AU7's and two 12AX7's it's all 12AX7's! Gee, I think that would do it.

    The users manual says nothing about replacing tubes, so I need someone to help me out here.


    -------front of unit-------
    ...........0...........0........
    ........................0........
    ...................0...0........
    -------back of unit--------


    The 0's are the tube sockets. Which sockets are the AU7's and which ones are the AX7's?


    :help: :help: :help: :help: :help: :help:
     
  2. Munjibunga

    Munjibunga Total Hyper-Elite Member Gold Supporting Member

    May 6, 2000
    San Diego (when not at Groom Lake)
    Independent Contractor to Bass San Diego
    Dunno, but I'll be surprised if it makes a significant difference.
     
  3. jasonbraatz

    jasonbraatz

    Oct 18, 2000
    Oakland, CA
    The problem is that there is distortion in places there shouldn't be, and controls that seem too sensitive. I can definitely see that a circuit designed for an AU7 would distort if a higher gain tube was installed.
     
  4. Munjibunga

    Munjibunga Total Hyper-Elite Member Gold Supporting Member

    May 6, 2000
    San Diego (when not at Groom Lake)
    Independent Contractor to Bass San Diego
    Perhaps.
     
  5. tombowlus

    tombowlus If it sounds good, it is good Gold Supporting Member

    Apr 3, 2003
    North central Ohio
    Editor-in-Chief, Bass Gear Magazine
    As I recall, the two tubes closest to the front panel are the 12AX7's, and the other three are the 12AU7's.

    Tom.
     
  6. metron

    metron Fluffy does not agree

    Sep 12, 2003
    Lakewood Colorado
    I wouldnt worry about high voltages in the preamp very much. Just dont go messing around in there with it on. :rolleyes: :D It will absolutely make a difference if you have all AX7s in there. Man I was just under the hood of that thing a few months ago changing them all out but I cant remember which is which. Email or call Aguilar and they will tell you for sure.
     
  7. inazone

    inazone

    Apr 20, 2003
    Colorado
    This is correct. When looking at the front, the input is on the left. the first two (front to back) are 12ax7. The rest are 12au7.

    I put tungsol tubes in mine and really like them. Very clear and tight but nice warmth at the same time.

    do a search, there is more info on the db680 and preamp tubes.
     
  8. jasonbraatz

    jasonbraatz

    Oct 18, 2000
    Oakland, CA
    Well just to clear things up, I emailed Aguilar, and heres what the schematic they sent me said:

    ----front------
    ......1.....2....
    ............3.....
    .........4..5....
    ----back------

    1, 4, and 5 are 12AU7's
    2 and 3 are 12AX7's

    also there are trim pots, which should help me pin down and eliminate any remaining distortion. :) ROCK.