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  • Help with sub 200hz

    So Ive built a soundbar for a friend of mine and am in the tweaking stages and am at a standstill. Im using the w5-1611sa full range drivers. Theyre in a .5cuft box tuned to 56hz. My trouble is very very low output below 200hz. Ive tried various amounts of stuffing to no avail. Ive tried some bsc and it helped but minute amounts. The only thing that could be off is the port. He actually made it 4 1/2 instead of 4. Shouldnt make that large of a difference. Does anyone have any ideas? Its driving me mad. Sent from my iPhone using Tapatalk Pro

  • #2
    Is f 56hz or box tuning?

    If f is 56hz, not box tuning, then 2" x 2.3" and box tuning is 65hz, with an f of 55.46hz.

    If box tuning is 56hz then the vent is 2" x 3.65" with f of 51hz

    2" x 4" vent gives box tuning of 52hz, f 50.12hz.

    They're all pretty close. Are they wired out of phase? More stuffing reduces port output.



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    http://techtalk.parts-express.com/fo...khanspires-but
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    • #3
      56 is box tuning, not sure why i wrote f3. They are wired in phase. I tried no stuffing to see if i was blocking the port and it didnt help whatsoever. I also tried sealing the port to create a large sealed box and still no change. Sent from my iPhone using Tapatalk Pro

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      • #4
        Look for leaks. If you tape up the port to make a smaller hole you can blow into the port to check for leaks. An impedance sweep would give the definitive answer.
        John H

        Synergy Horn, SLS-85, BMR-3L, Mini-TL, BR-2, Titan OB, B452, Udique, Vultus, Latus1, Seriatim, Aperivox,Pencil Tower

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        • #5
          Would a leak cause that much change? Sent from my iPhone using Tapatalk Pro

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          • #6
            Originally posted by jhollander View Post
            An impedance sweep would give the definitive answer.
            +1.

            www.billfitzmaurice.com
            www.billfitzmaurice.info/forum

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            • #7
              Until you measure we don't know how much we are talking about. Have re read this chance are there's no BSC correction. Do you have an x-o on the these?
              John H

              Synergy Horn, SLS-85, BMR-3L, Mini-TL, BR-2, Titan OB, B452, Udique, Vultus, Latus1, Seriatim, Aperivox,Pencil Tower

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              • #8
                Xmax @ 80Hz w/10w RMS?

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                • #9
                  Sounds like there has been no filtering for baffle step losses.

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                  • #10
                    Ive tried 1-3mH coils and 4-8 ohm resistors. My last test had 3mH and 8ohm resistor. It helped some but still worlds away from what it should be. I do not have any test equipment, just ran some frequency sweeps. 200hs is where it seems to drop pretty severely. Sent from my iPhone using Tapatalk Pro

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                    • #11
                      traced, guessed baffle, etc.

                      John H

                      Synergy Horn, SLS-85, BMR-3L, Mini-TL, BR-2, Titan OB, B452, Udique, Vultus, Latus1, Seriatim, Aperivox,Pencil Tower

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                      • #12
                        It may sound dumb, but did you break in the drivers? This is a modest driver with a 6g moving mass and 3mm Xmax. You may need to give the suspension a little help. If mechanical palpation doesn't do it, I'd run up the power at resonance frequency in free air (where impedance is 40 Ohms and nothing will overheat) until the cone got moving and let it run a few hours. Moving the cone with fingers is usually enough if there's a generous Xmech.
                        Frank

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                        • #13
                          Ive been working on breaking in the drivers some more. A few hours on 60hz tone. Even on 15w full volume it is pretty quiet. And that is free air too. Its strange and i cant figure out what is going on Sent from my iPhone using Tapatalk Pro

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                          • #14
                            They have a great midrange and are very clear but for lack of better words just sound like really articulate tv speakers; very thin Sent from my iPhone using Tapatalk Pro

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                            • #15
                              Originally posted by ameuba10 View Post
                              They have a great midrange and are very clear but for lack of better words just sound like really articulate tv speakers; very thin Sent from my iPhone using Tapatalk Pro
                              What are you using to drive the soundbar?

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