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BMAX INPUT GAIN MOD??

Discussion in 'Amps and Cabs [BG]' started by stanknuckle, Aug 17, 2007.


  1. Can someone explain what modification BBE make to their BMAX (SS) PREAMPs? I'm forever reading that you need to send it back to them for an INPUT GAIN mod but no threads on what the mod is. cheers.
     
  2. Crabby

    Crabby

    Dec 22, 2004
    There is lots on TB about this mod. Many owners of this preamp, like myself found that the unit had a ridiculously hot input stage. Even with a passive bass, the input volume control had to be turned down almost as low as it would go to avoid clipping.

    The pre amp has no input clipping lights so its ahrd to know whats going on until the sound gets really bad!

    I sent mine in and BBE modded it and sent it back (return shipping paid by BBE), and the problem was solved.

    I wasn't even the original owner so this was great customer service.

    For me, the pre amp still had issues with strange static noise that I could not get rid of, so I eventiually sold off the BBE. But if you find one that doesn't have this issue, its a very nice sounding unit for the price.
     
  3. afroman

    afroman Supporting Member

    Aug 31, 2000
    Austin, TX
    Yes, I used to own both the BMAX and BMAX-T. I had to setup the gain at about 1-2 and volume not much more than 4 to get stupidly loud. The mod apparently fixes this so you can dial more gain/volume settings w/o having your speakers blow up.

    Nice to know that they even pay shipping back to you. Now, if every manufaturer would do that.:rolleyes:
     
  4. bongomania

    bongomania Gold Supporting Member Commercial User

    Oct 17, 2005
    PDX, OR
    owner, OVNIFX and OVNILabs
    Seems like you could probably achieve the desired result by putting a larger resistor at the input. Try de-soldering one end of the input resistor, and using alligator clips to test different values of resistor clipped on between the existing resistor and the point where it used to connect (putting the two in series).
     
  5. Thanks Bongo, now we are getting somewhere....
     

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