How To Combat Speaker Cabinet Resonances

Comments · 89

• FO

  @Forensic_Audio · 2 years ago · pinned

  Below are some of the damping materials that I like to use:<br>Peel and stick butyl rubber sound dampening peel (Generic Dynamat): <a href="https://amzn.to/3Nk29nJ">https://amzn.to/3Nk29nJ</a><br>Sonic Barrier 3 layer system: <a href="https://amzn.to/3M7TXrb">https://amzn.to/3M7TXrb</a><br>Sonic Barrier foam 1/2&quot;: <a href="https://amzn.to/3S4GJzh">https://amzn.to/3S4GJzh</a><br>Polyfill: <a href="https://amzn.to/3Fn9RtR">https://amzn.to/3Fn9RtR</a><br>1/4&quot; MDF sheets to laminate inside of cabinet with: <a href="https://amzn.to/46VoGzG">https://amzn.to/46VoGzG</a><br>Carpet padding 3/8&quot;-1/2&quot; - Available at any home improvement store <br>Blu-Tack (great for making gaskets and sealing port holes): <a href="https://amzn.to/3CC3DoL">https://amzn.to/3CC3DoL</a><br>Dayton Audio DATS v3: <a href="https://amzn.to/43PBZAu">https://amzn.to/43PBZAu</a><br>Rockwool Acoustic Stuffing: <a href="https://www.acoustimac.com/roxul-rb6-2in?utm_term=&amp;utm_campaign=PMax/Insulation/2023&amp;utm_source=adwords&amp;utm_medium=ppc&amp;hsa_acc=4716037441&amp;hsa_cam=17880814997&amp;hsa_grp=&amp;hsa_ad=&amp;hsa_src=x&amp;hsa_tgt=&amp;hsa_kw=&amp;hsa_mt=&amp;hsa_net=adwords&amp;hsa_ver=3&amp;gclid=Cj0KCQjwhL6pBhDjARIsAGx8D595-ldQnngjCv6lEevkFWJpPpR4tMOCJ4-jHq2IIPRKGUDxeymsUukaApVnEALw_wcB">https://www.acoustimac.com/roxul-rb6-2in?utm_term=&amp;utm_campaign=PMax/Insulation/2023&amp;utm_source=adwords&amp;utm_medium=ppc&amp;hsa_acc=4716037441&amp;hsa_cam=17880814997&amp;hsa_grp=&amp;hsa_ad=&amp;hsa_src=x&amp;hsa_tgt=&amp;hsa_kw=&amp;hsa_mt=&amp;hsa_net=adwords&amp;hsa_ver=3&amp;gclid=Cj0KCQjwhL6pBhDjARIsAGx8D595-ldQnngjCv6lEevkFWJpPpR4tMOCJ4-jHq2IIPRKGUDxeymsUukaApVnEALw_wcB</a><br>My videos about upgrading speakers can be found here: <a href="https://www.youtube.com/playlist?list=PLg0Xq1LbiZBV3JdrXQtMPgv3Lc6YB6fdr">https://www.youtube.com/playlist?list=PLg0Xq1LbiZBV3JdrXQtMPgv3Lc6YB6fdr</a>

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• NE

  @NeilBlanchard · 2 years ago

  Here&apos;s a method I use to find the resonances in speakers - place the two speakers face to face, and wire one of them with the speaker wires inverted i.e. connect the positive wire to the negative binding post, and the negative wire to the positive post. Use an online tone generator to play tones from the bass up to treble (20Hz to ~5kHz). The main output from the drivers will largely be canceled out by playing a mono signal and one speaker being inverted. What you can then hear/feel is the cabinet resonances (and a few other things). If the cabinet &quot;lights up&quot; with vibration in certain areas, you can feel/hear where the weakest points are in the cabinet.<br><br>I would also <b>always</b> add a rib across the inside of the narrow web of the front baffle between the drivers. The movement of the woofer/midrange cone is always going to stress the weakest part of the baffle - which is always the narrowest &nbsp;web. A rib of 3/4&quot; plywood the is an 1&quot;- 1.5&quot; wide, glued on its edge across the width of the front baffle is a minimum. I would look at a strut connecting the new rib to the back baffle next - this adds a lot of stiffness to both the front and back baffles. You can also add ribs to the side panels that overlap with the rib on the front baffle at the corners; and a rib across the back baffle that is parallel with the front rib. You can go all the way and have a strut side to side and front to back, that are glued to each other in the middle - this forms a so-called window brace. The stiffness of all the speaker panels are multiplied by an order of magnitude. And the total reduction of the interior volume of the cabinet is fairly small.<br><br>Repeat this at a different height(s) in a tower speaker. It is a good idea to have the spacing of the ribs at ~1/3rd or ~2/5ths of a given panel span. This distributes the resonances and their harmonics out. Putting a rib/brace right at the midpoint of a panel will have stronger 2nd harmonic resonances that sum up for the two halves of the panel; if that makes sense?<br><br>I would advocate either for thin panels added to the cabinet panels (and possibly using silicon rather than glue) - OR - using foam like the carpet pad, or 3-layer damping foam like Parts Express sells on the remaining open panel areas. The foam won&apos;t displace the volume of the cabinet, and it will actually lower the tuning somewhat. If you use 1/4&quot; MDF panels with flexible glue/silicon, they will damp the panel <b>because</b> they flex a bit, and they won&apos;t displace as much volume as thicker panels.

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• NI

  @NicksStereoStuff · 2 years ago

  This was an awesome video. Very interesting. You make me want to try DIYing some things, haha.

  3

• RO

  @RobertCookcx · 2 years ago

  This is a fantastic video. I use the laminate process myself. One point is that if you stage the laminate pieces so they are non-uniform between parallel walls, that is also a benefit as you don&apos;t have walls coupling as you would if you simply have a brace. Nice work

  2

• BB

  @bbfoto7248 · 2 years ago (edited)

  Great video. &nbsp;Just note that this process and the materials used should be referred to as &quot;Damping&quot;, not &quot;DampENing&quot;, which would have to do with moisture issues, not resonance/vibration control.<br><br>In addition, the fibers from mineral wool/Roxul are also harmful and should also be contained. &nbsp;If you encapsulate the mineral wool within 3 mil thick plastic sheething or &quot;bags&quot; it will still be acoustically effective but will contain or encapsulate the fibers. &nbsp;<br><br>I have used &quot;Turkey Oven Bags&quot; for this because they are incredibly tough &amp; resilient and will not deteriorate over time. &nbsp;Find them in the cooking goods section in your local supermarket. &nbsp;They come in a small box similar to plastic Zip-Loc bags.<br><br>Personally, I always choose natural lambswool as my preferred &quot;fiberfill stuffing&quot;, which is not harmful to your health and is also one of the best performers in terms of these types of acoustic fiberfill materials.

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• MA

  @marieduty9279 · 10 months ago

  Thank you very much for the valuable info. well done

• BI

  @Birmingham_racing · 2 years ago

  Wish I knew more about this before getting rid of my kef q950s

  1

• BL

  @blakewillson18 · 1 year ago

  Awesome video, great stuff!

• AL

  @alexugljesic · 1 year ago

  I just saw this video, and it is great, because I am starting overhaul of my kit/DIY 3 way boxes, and I was thinking about laminating them from inside with MDF. Now, I am definitely do that. Thanks for sharing your process.

• BL

  @blaze2051 · 2 years ago

  Thanks!

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• BO

  @boriken395pr · 2 years ago

  Thanks! Well done!

• BU

  @buzzcrushtrendkill · 2 years ago

  Two pieces of cabinet material with a constraining layer of urethane between them.

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