Aguilar DB 750 - Circuit board mounts?

Discussion in 'Amps and Cabs [BG]' started by Khrist92, Jul 10, 2022.

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  1. Khrist92

    Khrist92 Supporting Member

    Apr 5, 2018
    New Jersey
    I had a DB750 shipped to me recently and had the opportunity to plug it in yesterday. Turned on fine, seemed super quiet. Former owner told me preamp tubes might've shifted during shipping and causing the quiet-ness. I pop it open and done tube is completely out of its socket, and another bent, and the top circuit board (see pics) seems like its come off its mounts and caused the issues during shipping. No pins from the tubes were stuck in the sockets, thankfully. I could not find a schematic or other gut shots after a cursory search online.

    To anyone else with a DB750 - do those posts actually mount to the board or just support it? There are 4 of them. To me it seems like the circuit board is held in by tension, given the two strips of white foam on top of the circuit board would be making contact with the top cover - I find it very unlikely all 4 screws sheared off so the power control board just "floats".

    I had some extra/used 12ax7's lying around so I was able to confirm the amp works properly after replacing the two with bent pins this morning - it was a LOT louder and no odd noise issues were detected. I didn't crank it as its still before 10 am where I live.

    DB 750 Guts.jpg Circuit board mounting_.jpg
     
    Last edited: Jul 10, 2022
  2. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
    Nope, it looks like M-F standoffs were used and were either overtightened or damaged during shipping. This can be a real pain to repair, the top M-F standoffs need to be replaced and if the broken studs can’t be removed from the bottom standoff, they will have to be replaced as well.

    They are probably 4-40 but you need to verify and measure the length.

    Be super careful not to cause new damage when doing the repair.
     
    daddymactx and Khrist92 like this.
  3. Khrist92

    Khrist92 Supporting Member

    Apr 5, 2018
    New Jersey
    Thank you for your guidance. Looks like I'll have to replace both. So far they have all easily come out of the threaded holes on the bottom of the case and the circuit board. It also looks like the top parts were replaced when the damage first occurred and the white foam was placed there to hold the board in place. Would I have to contact Aguilar for new ones or can they purchased elsewhere? Took pictures to show approximate length and sheared part.

    Post 1.jpg Post 2.jpg Sheared.jpg PXL_20220710_145846073.MP.jpg PXL_20220710_145854116.MP.jpg
     
  4. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
    The foam is to keep the top cover from rattling.
     
  5. Wasnex

    Wasnex

    Dec 25, 2011
    FYI Aguilar requires people to sign an NDA before receiving schematics, so you don't tend to see them widely distributed online.