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OK, is a preamp needed for feedback issues?

Discussion in 'Amps, Mics & Pickups [DB]' started by Flat Bass, Oct 27, 2004.


  1. Flat Bass

    Flat Bass

    Dec 8, 2002
    I am having more trouble with my K&K bassmax with feedback. Should a preamp help with the feedback issues? Is a phase switch needed on the preamp? What is the deal? Would a Raven Labs preamp do it? What about one of the K&K preamps? I am just tired of wrestling with feedback. It just causes me to have very inconsistent tone you know. :help:
     
  2. Chris Fitzgerald

    Chris Fitzgerald Student of Life Staff Member Administrator

    Oct 19, 2000
    Louisville, KY
    Here are a couple of things you can try:

    1) Mute the afterlength of the strings (between the bridge and tailpiece) with foam, felt, or anything that keeps them from vibrating. When I was playing a BM equipped bass as my main axe, this cleared up 90% of all feedback problems.

    2) Identify the problem frequencies. Is it a low "woofy" feedback, or is it more of a "screeching" high-pitched sound? A good way to do this is to get your hands on a decent parametric EQ (borrow one if you can), turn up the volume, and then try to "seek and destroy" the feedback with a variable notch filter. The beauty of parametrics is that they are built for "seek and destroy".

    3) Reexamine the relationship between the placement of your amp and your bass. If your amp is driving sound directly into the body of the bass, that's a sure-fire recipe for a feedback loop. Try getting your speaker high off the ground so it doesn't sound right into the bass, or try tilting it up toward the ceiling at an angle, which can also be very effective.

    Hope this helps.
     
  3. Flat Bass

    Flat Bass

    Dec 8, 2002
    Yeah thanks alot Chris. I talked to Bob G today and he told me the preamp is not my problem. I think I am going to try and put some foam like you said in between the tail piece and body. I am also going to try and wrap or insulate, if you will, the wire going from the input to the actual piezo piece on my K&K bass max. My feedback if always a low end woofy feedback. Usually when it is feeding back if I grab the wire in between the input and the actual piezo it will usually stop instantly.
     
  4. Chris Fitzgerald

    Chris Fitzgerald Student of Life Staff Member Administrator

    Oct 19, 2000
    Louisville, KY
    I bet the afterlength dampening solves your problem, as this is where the low "woofy" feedback most often comes from, IME. You may be damping the afterlength strings in order to get to the pickup wire as well. Let us know how it turns out.
     
  5. Flat Bass

    Flat Bass

    Dec 8, 2002
    Chris,
    You da man!I just checked out your website and read up on you and am listening to you right now. Man great tone, intonation, and playing in general. Is that red thing wrapped around your strings in any relation to what we have been talking about with feedback? Maybe I will try tying a hanker chief around my strings and pickup wire in the same spot. I am working on my bachelors in performance right now. I am currently in theory III/ Aural skills III. Where is a great program for me to go and get my Masters?
     
  6. Chris Fitzgerald

    Chris Fitzgerald Student of Life Staff Member Administrator

    Oct 19, 2000
    Louisville, KY
    Thanks for the kind review. Yup, that red thing is a piece of piano felt tied tightly around the afterlength on my old Czech bass, which still has a double bass max, BTW. My new bass hasn't needed the same treatment because of the Full Circle/AMT combination, but I haven't played much high volume stuff since getting it, either.

    Where are you located, and what are your goals as a player?
     
  7. Flat Bass

    Flat Bass

    Dec 8, 2002
    Chris,

    I am in the southeast US. I am in Birmingham, AL. right now going to UAB. As far as my goals I would like to be the best bass player I can be on upright and electric. I guess my real life goal right now is to just graduate and go on to my masters. Then maybe get a job teaching Fundamentals, theory I or II and playing in a Jazz group on the side. I am realizing more and more that my goals of actually touring with someone big are getting less and less. But the real job thing is getting closer and closer :help: . Anyways thanks alot for letting me take your time.

    Thanks,
    Freddie Smith
     
  8. Chris Fitzgerald

    Chris Fitzgerald Student of Life Staff Member Administrator

    Oct 19, 2000
    Louisville, KY
    So I take it you're more of a jazzer then than a legit player...you have plenty of options. If you want to end up teaching, you'll want to think about what level you want to prepare to teach. If elementary, middle, or high school, then you'll probably want to look into an education masters, whereas if you want to end up teaching bass, that's obviously more of a performance kind of thing. If you want to teach at a university, you'll need at least a Masters and perhaps a Doctorate, depending on the particulars of who's hiring where.

    I guess if I were you I'd look very closely at what I wanted to specifically get out of a graduate program before I went shopping. Once I knew what I wanted, then I'd have a better idea of what schools were right for me.

    How'd that feedback thing turn out? :D
     
  9. Flat Bass

    Flat Bass

    Dec 8, 2002
    Chris,

    I wrapped a rag around my strings where yours is wrapped around on yours. I plugged it up last night and stood right in front of my rig even facing it and no feedback? :bassist: :hyper: Maybe it has something to do with different rooms also. I hope this is the ticket.
     
  10. dvmweb

    dvmweb

    Apr 20, 2002
    Atlanta MI 49709
    Even though you have solved your problem, I would consider adding a preamp with your Bassmax. If you are satisfied with your sound ok, but, if you want to add to your sound, then get a pre amp. It will allow you to shape your sound more and maybe even get more volume.

    If you feel the need to add to your rig I would get one.

    I don't play at high levels. When I first got my URB I played directly into my amp. Since I have bought a Fishman Bass ProEq. It sounds better. It is hard to describe but you add a little compression, and eq, it some and the tone is fuller and just "there". I got mine from Bob G. He's a good guy to deal with. :hyper:

    Walt MI/US
     
  11. fdeck

    fdeck Supporting Member Commercial User

    Mar 20, 2004
    Madison WI
    HPF Technology LLC
    If nothing else, a preamp will give your pickup the frequency response that it was designed for, and you will get more consistent results from one amp to the next. FWIW, with piezo pickups, a higher impedance preamp is also lower noise, though it takes a bit of math to prove this.