Subwoofer Insulation

Early B.
Early B. Posts: 7,900
edited November 2005 in DIY, Mods & Tweaks
I read Gaara's thread re: tweaking his Supernova with Dynamat and it got me thinking about subwoofer insulation. What is the best way to insulate a subwoofer?

I used a generous amount of inexpensive wave style foam in my sub (see pic).
I'm wondering if Dynamat or some other type of insultation would work better. I also heard that using peel-n-stick floor tiles work well, too. Very cheap.

Also, how much insulation do you add? In the SVS I used to own, there was only a smattering of insulation, but in the one I built, I covered up 80% of the interior walls. Should I re-do my work????

Thanks.
HT/2-channel Rig: Sony 50” LCD TV; Toshiba HD-A2 DVD player; Emotiva LMC-1 pre/pro; Rogue Audio M-120 monoblocks (modded); Placette RVC; Emotiva LPA-1 amp; Bada HD-22 tube CDP (modded); VMPS Tower II SE (fronts); DIY Clearwave Dynamic 4CC (center); Wharfedale Opus Tri-Surrounds (rear); and VMPS 215 sub

"God grooves with tubes."
Post edited by Early B. on

Comments

  • Dennis Gardner
    Dennis Gardner Posts: 4,860
    edited November 2005
    Sub insulation is less important than wall flex. With that said, I covered the walls of mine with open cell foam about 2 inch thick.
    HT Optoma HD25 LV on 80" DIY Screen, Anthem MRX 300 Receiver, Pioneer Elite BDP 51FD Polk CS350LS, Polk SDA1C, Polk FX300, Polk RT55, Dual EBS Adire Shiva 320watt tuned to 17hz, ICs-DIY Twisted Prs, Speaker-Raymond Cable

    2 Channel Thorens TD 318 Grado ZF1, SACD/CD Marantz 8260, Soundstream/Krell DAC1, Audio Mirror PP1, Odyssey Stratos, ADS L-1290, ICs-DIY Twisted , Speaker-Raymond Cable
  • tryrrthg
    tryrrthg Posts: 1,896
    edited November 2005
    The insulation in your SVS was most likely there to "fool" the driver into "thinking" the enclosure is bigger than it is. From what I've read polyfil or fiberglass insulation are the best things to stuff subs with. The stuffing are also in there to absorb high frequency info that passes through the crossover. Dynamat would only help with cabinet resonances, you would still want some stuffing in your enclosure.

    Here is a good discussion on stuffing

    I'm still trying to find a good article on stuffing...
    Sony KDL-40V2500 HDTV, Rotel RSX-1067 Receiver, Sony BDP-S550 Blu-ray, Slim Devices Squeezebox, Polk RTi6, CSi3 & R15, DIY sub with Atlas 15
  • VR3
    VR3 Posts: 27,970
    edited November 2005
    I am an advocate of FOAM... (as you already know)

    That Sonicbarrier stuff on PE, although expensive is awesome. I'm being serious... very dense foam.

    Their other type of eggcrate foam is alot different than regular egg crate and is also very dense....

    Foams does what Polyfill does - and it also dampens the panel (when coupled to the panel) - so I think its better.
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • tryrrthg
    tryrrthg Posts: 1,896
    edited November 2005
    That's the thing, I wouldn't want something very dense. The two things you want stuffing to do is absorb high frequency info that makes it through the crossover and make the enclosure "appear" larger by slowing down the air inside. something dense will just reflect high frequency info and actually take up enclosure volume because it's too dense for the air inside the enclosure to pass through. I could however see the merits of it on the enclosure walls.
    Sony KDL-40V2500 HDTV, Rotel RSX-1067 Receiver, Sony BDP-S550 Blu-ray, Slim Devices Squeezebox, Polk RTi6, CSi3 & R15, DIY sub with Atlas 15
  • Early B.
    Early B. Posts: 7,900
    edited November 2005
    I pulled the most salient quotes from the link given:

    "Ported boxes are lined with damping material, sealed boxes are stuffed at a rate of 0.5-1.5 lb/cu ft."

    "Start with 1 lb/cu ft. Then add more damping in 1/4 lb increments, as long as the bass continues to 'tighten' add more damping. At the point where the bass no longer tightens, and the only effect is a drop in the overall output level, remove the last amount of damping added."

    "A few rules of thumb: Stuff small enclosures – those with up to about 3 cubic feet of internal volume or less – with 1.5 pounds of fiberfill for each cubic foot of internal volume and you should get about a 30-percent increase in box volume without seriously affecting other performance variables. For larger enclosures, add stuffing at a rate of approximately 1 pound per cubic foot and you should get a virtual-space boost of about 25 percent."
    HT/2-channel Rig: Sony 50” LCD TV; Toshiba HD-A2 DVD player; Emotiva LMC-1 pre/pro; Rogue Audio M-120 monoblocks (modded); Placette RVC; Emotiva LPA-1 amp; Bada HD-22 tube CDP (modded); VMPS Tower II SE (fronts); DIY Clearwave Dynamic 4CC (center); Wharfedale Opus Tri-Surrounds (rear); and VMPS 215 sub

    "God grooves with tubes."
  • Early B.
    Early B. Posts: 7,900
    edited November 2005
    Thanks for the info, fellas. I suppose I'm OK with what I did. Here's a link to the pics of the sub while it was being built. It shows the amount of foam I added. The foam is about 1 inch thick and is not very dense.

    http://www.polkaudio.com/forums/showthread.php?t=28961&highlight=Atlas+DIY
    HT/2-channel Rig: Sony 50” LCD TV; Toshiba HD-A2 DVD player; Emotiva LMC-1 pre/pro; Rogue Audio M-120 monoblocks (modded); Placette RVC; Emotiva LPA-1 amp; Bada HD-22 tube CDP (modded); VMPS Tower II SE (fronts); DIY Clearwave Dynamic 4CC (center); Wharfedale Opus Tri-Surrounds (rear); and VMPS 215 sub

    "God grooves with tubes."
  • VR3
    VR3 Posts: 27,970
    edited November 2005
    Its not THAT dense... it will allow sound to pass through it very easilly - its just not a lightweight material like polyfill...

    The Eggcrate foam PE sells, although denser than regular eggcrate foam is a nice material to use... the sonic barrier stuff is designed specifically for what you're talking about though.
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • madmax
    madmax Posts: 12,434
    edited November 2005
    I'm being serious...

    You have been very serious lately Sid Serious. :D
    madmax
    Vinyl, the final frontier...

    Avantgarde horns, 300b tubes, thats the kinda crap I want... :D
  • VR3
    VR3 Posts: 27,970
    edited November 2005
    Im seriously not serious this time that Im serious...

    That would make me seriously unserious... seriously... this is retarded.
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.