Dual 20-39 CS+ Frequency response

Discussion in 'Archived Threads 2001-2004' started by ShalM, May 4, 2002.

  1. ShalM

    ShalM Extra

    Joined:
    Dec 29, 2001
    Messages:
    16
    Likes Received:
    0
    Trophy Points:
    0
    Hi,
    I am looking for some help/opinion from some of the experienced members of the forum. Here is a Frequency response using sine waves disk and Radio shack SPL meter that I obtained and graphed using the excel file available at sonnie's site.
    I was just wanting to know what you guys think about the curve and if the dips or peaks are significant enough to warrant an equilizer. Would I get a significant improvement using a BFD. By the way this is for a Dual SVS 20-39 CS+ with a Samson S1000 amp, and my preamp is at -20 dB volume.
    Will appreciate any opinions and guidance on this.
    http://www.villagephotos.com/pubimage.asp?id_=252709
     
  2. Ned

    Ned Supporting Actor

    Joined:
    Feb 20, 2000
    Messages:
    838
    Likes Received:
    0
    Trophy Points:
    0
    Well, do you think it sounds uneven now? It may not graph linearly but if you're happy with the sound then forget about it. If you did get a BFD, the only correction needed would be to reduce the peak at 40hz. The rest is pretty good and you could achieve a nice rising response from 80 down to 20hz. Play with the sub positioning before spending the money on a BFD. Where are your subs placed now?
     
  3. ShalM

    ShalM Extra

    Joined:
    Dec 29, 2001
    Messages:
    16
    Likes Received:
    0
    Trophy Points:
    0
    I have both the subs placed together in front corner. They do sound very good. I guess its just a quest to see if I am missing anything significant. I was myself surprised to see that the curve was fairly reasonable except for that little peak at 40 Hz and the dip at 50 Hz and thats what I was really curious if it would be considered anything significant by others who might have been through this kind of a path.

    I might play around a little with sub positioning though cant do much in that department coz of the room layout.

    Thanks for the reply Ned.
     
  4. SVS-Ron

    SVS-Ron Screenwriter

    Joined:
    Jun 2, 2001
    Messages:
    1,074
    Likes Received:
    0
    Trophy Points:
    0
    Shal,

    Tom might happen along later and has forgotten more about bass equalizaton than I know, but the general rule of thumb for simple guys like me is that is that you can generally trim room-induced "peaks" pretty effectively... should you want flatter response than you have already.

    "Nulls" as the mild one you are getting at 50Hz can only really be dealt with by repositioning (even moving one sub a few inches can have a radical effect here) or more complicated "bass traps" and such. Some mild boost there might help a bit, but if nothing else changes it can turn into a black hole of amp power too.

    As has already been suggested your response is VERY good actually, but a simple device like the BFD or the ART 351 would work very well to help. Even if you got things flatter you might not notice much difference.

    BTW, very nice job on the chart!

    Ron
     
  5. ShalM

    ShalM Extra

    Joined:
    Dec 29, 2001
    Messages:
    16
    Likes Received:
    0
    Trophy Points:
    0
    Thanks Ron for stopping by and giving me a good input.

    Two votes for repositioning the subs a bit means I really ought to try that.

    " Even if you got things flatter you might not notice much difference " ...

    That kind of opinion is really what I was looking for as to whether the little dip is worth meddling with or just be happy and enjoy the terrific subs. Anyway, appreciate your thoughts.

    Regards.
     

Share This Page