Need solutions for flattening frequency response....

Discussion in 'Speakers' started by Jeff_Wi, Oct 19, 2004.

  1. Jeff_Wi

    Jeff_Wi Stunt Coordinator

    Joined:
    Sep 13, 2004
    Messages:
    53
    Likes Received:
    0
    I recently ran some frequency sweeps using Spectrum Lab and a Radio Shack spl meter.

    http://pg.photos.yahoo.com/ph/cr8250/album?.dir=/8848

    Can someone recommend what is the best approach to reducing the nasty bump centered at 80Hz? I have read about the BFD being good for this, but what about broadband eq, such as a 31-band eq? I have tried multiple xover settings and phase settings. The problem is actually coming from my mains, in conjuction with the room properties
     
  2. MingL

    MingL Stunt Coordinator

    Joined:
    Mar 26, 2003
    Messages:
    214
    Likes Received:
    0
    The free way is to adjust the x-over on the sub to a lower value.

    At 80Hz, it may be the case that both the subs and mains are active at the same time and they are reinforcing each other (thats probably why 80hz is approx 6dB higher)

    Maybe try crossing over at 60hz or 70hz and things may just measure better.
     
  3. Jeff_Wi

    Jeff_Wi Stunt Coordinator

    Joined:
    Sep 13, 2004
    Messages:
    53
    Likes Received:
    0
    Well, actually the xover is set to the lowest of 40Hz. I measured the response of the sub only and the true slope is at about 70Hz -3db. By the way, can anyone see my graph? It was there at first, I think. Now it isn't.
     
  4. MingL

    MingL Stunt Coordinator

    Joined:
    Mar 26, 2003
    Messages:
    214
    Likes Received:
    0
    Don't see it now.

    Could you post the graph of the subs alone, mains alone and the sub+mains superimposed on the same graph? Its easier to see things this way sometimes.
     
  5. Jeff_Wi

    Jeff_Wi Stunt Coordinator

    Joined:
    Sep 13, 2004
    Messages:
    53
    Likes Received:
    0
    Ok, finally got the graph to work. As soon as I get a chance, I will do a comparison graph.
     
  6. Mark Seaton

    Mark Seaton Supporting Actor

    Joined:
    Oct 10, 1999
    Messages:
    600
    Likes Received:
    0
    Real Name:
    Mark Seaton
    First try setting the crossover for the mains up at ~80Hz. Then measure again.
     

Share This Page