1. Register NOW and become part of this fantastic knowledge base forum! This message will go away once you have registered.

bass boost proximity effect?

Discussion in 'Bass' started by Marcelo, Apr 11, 2002.

  1. Marcelo

    Marcelo Guest

    I am having a little trouble understanding the cancelling of high frequencies due to closeness of directional mics to the sound source. what´s the relation between high freq and it´s wavelenghts coming from 0 degrees cancelling at the mic diaphragm? and why does the dual capsule omni mode exhibit so little effect? I know single capsule omnis don´t at all.any help will be much appreciated.Thanks
  2. realdynamix

    realdynamix Well-Known Member

    Feb 23, 2001
    This is very basic , so forgive all the missing details..
    It's not canceling the highs; it's increasing the low frequency with proximity effect. I think you are referring to figure 8 setting as dual mono?
    (I could be way off here thinking that, if so, let me know), the figure 8 setting is designed to cancel at the sides, not the rear as in cardioid designs, which give the effect that you describe because some sound is allowed to reach the back of the capsule through a small opening. At close distance, the mic itself becomes an obstacle to the high frequencies at the rear, where the bass will wrap around and enter the port at the rear increasing the low end. Some mics have a roll-off to help flatten the response back out, and some like EV RE-20, or PL-20 have variable roll off as you get closer.
    Hope this helps,

  3. Bear's Gone Fission

    Bear's Gone Fission Active Member

    Jan 4, 2001
    My understanding was he was asking about a double-sided presure gradient capsule (ala U87 or 414) with bothe sides used in omni mode as opposed to a true presure transducer omni, which most small diaphragm omni condensors are.

    Doesn't help me come up with a good answer, though, as I'm not quite clear on what's going on. Phase cancellation between two or more mics?


Share This Page