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"Increased Headroom"

Discussion in 'Pickups & Electronics [BG]' started by Floating teetH, Sep 21, 2004.


  1. What does this mean? I see it all over. I searched for a definition, but all I found was, "electronics, dynamic headroom." What's up with that? Is dynamic headroom something that can't be measured in any way except to say "increased"?
     
  2. brianrost

    brianrost Gold Supporting Member

    Apr 26, 2000
    Boston, Taxachusetts
    Are you asking relative to pickups only or relative to the whole signal chain (amps, etc.)

    Any pickup will have a maximum output. No matter how much closer you get the string to the pickup, how much more string mass you have, how much more string moton there is, at some point the pickup can't generate any more signal (this is usually called "saturation"). If the pickup feeds into an onboard preamp (i.e. an "active" bass) then the signal is further limited by the power supply. Some active systems use two (or more!!) 9V batteries because the increased supply voltage allows a higher maximum output voltage.

    The point is not to increase output to get more volume but to allow a wider dynamic range, i.e. the difference between the softest and loudest parts of your playing can be greater. At some point it's overkill...if the bass' output is undistorted even if pound on the strings with a jackhammer then you probably have enough headroom :p

    On the other hand if you are after a compressed or distorted tone, you don't need as much headroom.
     
  3. I started thinking about this in relation to pickups w/ the 18V option. Then I remembered reading about it all over, in stuff about mixers etc. I was almost convinced it was a hoax (like second hand smoke or the ozone layer) due to there being no actual measurement of any sort that is associated with headroom.
    :meh:
     
  4. Lyle Caldwell

    Lyle Caldwell

    Sep 7, 2004
    Memphis
    Not a hoax. Increased voltage can not only give cleaner gain and more headroom, but respond faster to attack transients, making the sound more detailed and responsive.

    Notice I said "can." It depends on the circuit- there are lots of bottlenecks on transients and clean gain, but assuming everything else is the same, more voltage is a good thing.
     
  5. Passinwind

    Passinwind I Know Nothing Supporting Member

    Do a Google on "IHF dynamic headroom measurement". This is a power amplifier measurement, but it'll give you an idea how dynamic headroom can be (and is) quantified.