Aguilar OBP-1 can handle 9-48V????

Discussion in 'Pickups & Electronics [BG]' started by Mario Lewis, Jan 4, 2002.

  1. Mario Lewis

    Mario Lewis

    Jul 6, 2001
    Clinton, MD
    At the bass gear review archive site, there is a link for a page that has information reprinted with the permission of Mr. dave King. There he offers advice on different preamps that can be used in his custom built instruments. He says that the Aguilar OBP-1 can handle from 9 to 48V. That is 5 9volt batteries wired in sequence. What kind of benefit would this offer? My Alembic only uses one 9 volt and it is EXCELLENT!!!! Why would a preamp need any more than 18 V? What advantage would 3 or 4 batteries give my tone that one or two wouldn't?
  2. more volts gives you more headroom. but the use of every battery beyond the first sinks exponentially.

  3. geshel


    Oct 2, 2001
    I don't get it. What do those numbers represent, and how did you get them?
  4. Nightbass


    May 1, 2001
    Seattle, WA
    Unless there's some sort of onboard voltage regulation, which I suspect there is for the following reasons:

    From the install sheet, it's clear that the amp is a single-ended amp, running on a +18V power source instead of +9V and -9V like a double-ended amp.

    I think the reason Aguilar designed it to handle 48V is not so that you would use 5 batteries (which is absurd!), but so that you can run it off of DI phantom power, if your bass is wired with an XLR jack. Shades of the external power supply on the Alembic Series basses. :)

    Hence, if the amp is going to give you the same output regardless of the supply voltage, then it probably has a voltage regulator.

    Write to Aguilar and get the story, though.

  5. well i was trying to represent what i meant by the exponential sinking of the use of each battery beyond the first....

    well it doesn't really matter
  6. geshel


    Oct 2, 2001
    Matters to me! :) Exponential sinking of *what*? I really haven't a clue as to why whatever "headroom" means doesn't increase linearly with the number of volts supplied.
  7. geshel


    Oct 2, 2001
    OK, I think I get what you mean. For a signal of a given RMS, if half the signal is contained within 9v, 75% will be within 18v, 7/8 within 27v, etc. Of course it depends on the statistics of the signal really, etc.
  8. ok that's more or less what i was talking about