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Should I try a Notch Filter?

Discussion in 'Amps, Mics & Pickups [DB]' started by NickyBass, Mar 9, 2006.


  1. NickyBass

    NickyBass Supporting Member

    Nov 28, 2005
    Southern New Jersey
    I was wondering what anyones expierience with notch filters are. I would like to control feedback, but am not a techie. How easy is it to find the offending freq, and is it usually the same freq, or does it change from room to room? My thoughts; turn up the amp to the point where it starts to feedback, then twist the notch filter until the feedback is subdued. But wouldn't that make those notes softer than the rest? How much more gain can I realistically expect?
     
  2. anonymous0726

    anonymous0726 Guest

    Nov 4, 2001
    Did you mean to post on the Slab side?
     
  3. brianrost

    brianrost Gold Supporting Member

    Apr 26, 2000
    Boston, Taxachusetts
    My experience has found that notch filters do help a bit but you don't get HUGE increases in gain before feedback kicks in again (usually at a DIFFERENT frequency). Yes, use of any extreme EQ can cause certain notes to sound very weak by removing too much signal.

    A much better solution I found was to dampen the tailpiece with foam (stuff some between the tailpiece and body)...some guys even use towels for this! Then roll off some bass EQ so that body resonances that are BELOW the open E string don't excite upper harmonics. For instance I found that feedback I often got an octave above the open A string (sometimes closer to Bb) could be tamed this way. Many preamps for bass pickups have phase inversion switches and these are very worthwhile in fighting feedback.
     
  4. seamonkey

    seamonkey

    Aug 6, 2004
    The Feedback eliminators have some very narrow notches and are good about not causing a bunch of phase problems (keeping it sounding natural)

    I shouldn't mention the "B" word, but I did notice that they're showing up even in hi-fi systems.

    http://www.partsexpress.com/projectshowcase/colossi/index.html
    http://www.partsexpress.com/projectshowcase/colossi/list.html

    I've been kicking around the thought of picking up a FBQ2496 for feedback and tone shaping, or jumping up to a DEQ2496 to also use in a home studio.
     
  5. brianrost

    brianrost Gold Supporting Member

    Apr 26, 2000
    Boston, Taxachusetts
    Actually I tried my Behringer Feedback Exterminator once with my DB and while it removed the feedback the resulting tone was reallly odd with all the notches in response.
     
  6. seamonkey

    seamonkey

    Aug 6, 2004
    Good to know.
    Was the the FBQ2496, the previous model, or a shark?
    Just wondering which one not to try.
     
  7. NickyBass

    NickyBass Supporting Member

    Nov 28, 2005
    Southern New Jersey
    Thanks for the info guys. The unit that I was considering was the D-TAR Equinox. I've heard great things about the eq, so even if the notch filters don't give me a whole lot more gain, I would still have a nice eq that can double as a preamp. If I decide to get one, I will post an update here.
     
  8. Bob Rogers

    Bob Rogers Left is Right

    Feb 26, 2005
    Blacksburg, Virginia
    I had an early model Behringer feedback destroyer for PA and got rid of it quickly. The automatic feature was awful - tone deteriorating at random times during a gig. It was also rather noisy, so even using it with fixed notches wasn't worth it.
     
  9. B String

    B String Supporting Member

    Apr 11, 2002
    Los Angeles
    I could be wrong, but I don't think the D-tar has a notch
    filter on it, only lows, mids and highs. The notch filter on
    my Focus has come in quite handy. I had never owned one
    before. It took about two minutes to get it, and I only use it
    once in a while, but it comes in handy when I do need it.
     
  10. Rick Turner

    Rick Turner Commercial User

    Jul 14, 2004
    I design and build electric basses and pickups under the Turner, Renaissance, and Electroline brand names.
    B-String, you're confusing the D-TAR Equinox, a three band parametric EQ plus two bands of notch filtration with the Solstice mixer/blender. The Equinox will fit the bill here if you like it's feature set and sound.

    I'm the "T" in D-TAR
     
  11. B String

    B String Supporting Member

    Apr 11, 2002
    Los Angeles
    Rick. You are correct. I'm such an idiot! I'm so stupid! Why
    can't I learn to read? Whats the frekkin matter with me???
    oohhh..... ok.....I feel better now. Sorry about the bad info.