...Looks like I need a BFD

Discussion in 'Archived Threads 2001-2004' started by Scott Simonian, Jun 23, 2002.

  1. Scott Simonian

    Scott Simonian Screenwriter

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    I have been enjoying my 210L Tempest for a few months now. I am constantly blown away by its performance, so much better than my DefTech.

    Anyway, I am still noticing one thing that I have always had a problem with: the non-flat response of my room. I have moved the sub in more places than Id like to list. I found the best spot to be on my right, front corner.

    Here are the measurements at the listening position:


    These values are corrected.
    10Hz 78db
    12.5Hz 88db
    16Hz 85db
    18Hz 92db
    20Hz 97db
    22Hz 98db
    25Hz 97db
    28Hz 100db
    31.5Hz 102db
    36Hz 108db
    40Hz 106db
    45Hz 100db
    50Hz 96db
    56Hz 105db
    63Hz 101db
    71Hz 105db
    80Hz 106db
    89Hz 95db
    100Hz 102db
    111Hz 97db
    125Hz 87db
    142Hz 86db
    160Hz 83db


    *Please note that when measuring I had my sub level up a little "hot" and since been running it about -6db instead of 0. I was taking these for a reference of how good or bad my response was, not to properly calibrate.



    Sigh. This is not an ideal frequency response for in-room. I was wondering if this would be a good scenario for getting a BFD. I dont know a whole lot about it. Just that everyone likes to use it as a para. equalizer.

    Is it presise to 1/6 octave? Can I "perfectly" smooth out my response? If it is possible, where is a good (reputable), place to get one?



    Oh and that link for the turtorial too. :b
     
  2. Craig Woodhall

    Craig Woodhall Supporting Actor

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    Scott,
    just sitting down to watch a movie, and don't have much time to address your post im sure more qualified people will jump in..
    I just bought a BFD for my tempests and love it.. As for places to buy them, im in Canada, so that doesn't help ya.. Ebay, or any number of online music stores in the US will have it. I think about $120 US is what you should shoot for..
    here is one of the links for you.
    http://www.snapbug.ws/bfd.htm
    Craig
     
  3. ThomasW

    ThomasW Cinematographer

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  4. TedO

    TedO Stunt Coordinator

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    I just ordered one from Zzsounds. $119 + $5 shipping.

    TedO
     
  5. Nice TedO!
    Let us know when you get it in[​IMG]
     
  6. jeff lam

    jeff lam Screenwriter

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    Go to guitar center if you have one nearby. You can deal them down to around $120 or so.
     
  7. Scott Simonian

    Scott Simonian Screenwriter

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    Craig - Thanx, thats the site I was looking for. [​IMG]
    Okay, I can see that I dont have to worry about the price. Good.
    What about my situation? How well can I fix it?
     
  8. I have seen much uglier things fixed!

    going from +/-15db to +/-3 or 5 db is a big difference=)
     
  9. Wayne A. Pflughaupt

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    Scott,
    A tip before you spend your money: Make sure your phase setting is correct. Improper phase can have an adverse affect on response an octave or more on both sides of the crossover point. Since your sub is at the front of the room, set your phase according to your crossover slope:
    • 1st order (6dB/octave) - 45deg.
    • 2nd order (12dB/octave -90deg.
    • 3rd order (18dB/octave) - 135deg.
    • 4th order (24dB/octave) - 180deg.
    After you adjust the phase take new readings with both the subs and mains on. If your phase was incorrect before, you should see considerable improvement. You will probably still benefit from the BFD, but you will have an easier response curve to correct.
    Regards,
    Wayne A. Pflughaupt
     
  10. Scott Simonian

    Scott Simonian Screenwriter

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    Anthony - Its good to see that it isnt imposiible. [​IMG] [​IMG]
    Wayne - Trust me. I have done more tweaking with the phase than I have changing spots. Thats saying a lot! It is currently set at 90*. In my case, this was the more tolerable freq. curve. There were dips and peaks on different spots. When I left it where it is now, I had the least amount of dips in the low 15hz - 30hz area.
     
  11. Wayne A. Pflughaupt

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