Stuffing sealed shiva.. (1 Viewer)

[Seungsoo Hwang]

I am almost completed with my sealed shiva sub, and it appears the final volume with all accounted will be around 2.5 ft^3. How does one know to stuff, why to stuff, and how much to stuff

?. The sub will be playing mostly music, of the techno/rock variety, and movies once in a while. Thanks!

 

[Greg Monfort]

For your app, I wouldn't. I would also experiment with smaller volumes, like 1.5ft^3, by adding bricks or similar for more mid bass 'punch'.
GM
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Loud is beautiful, if it's clean

 

[Julian Data]

"Bricks"????????

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[Seungsoo Hwang]

Hmm interesting. Just out of curiosity, what would be the effects of it if I did stuff it? I know that the enclosure volume appears to be larger to the driver, and would lower the Q of the sub.. what is happening?
thanks for the suggestion.

 

[Julian Data]

The sound waves travel behind the cone travel slower thus..
following the driver that the box is bigger..
and..
You are dampening the driver.
I would start 25% fill and then work up to 50% See if there's a difference. It should be theorectically.
Remember 1lb of stuffing per cu ft.

 

[Jack Gilvey]

Well, I'd certainly follow GM's advice and listen to it unstuffed first. One thing about stuffing, it's easy, cheap, and reversible. Experiment. For some apps/tastes, an overdamped alignment can sound "weak", hence the advice on making the box "smaller".
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[Brian Bunge]

I agree with Julian's recommendation as far as stuffing is concerned. I just have one pet peeve about something he said. Stuffing the enclosure in no way DAMPENS anything! Now it does DAMP soundwaves but in order to dampen something, you need to add some type of liquid.
I'm not meaning to pick on you Julian, you were just in the wrong place at the wrong time! And my mom wanted to be an English teacher so certain things get under my skin (that doesn't mean I don't make plenty of errors myself, though). I even see this in major publications so it's pretty widespread. OK, off the soap box now!
Again, I do think starting with 25% to 50% stuffing is a good rule of thumb if you are going to stuff the cabinet.
Brian
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[Julian Data]

My bad!
hehe
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[Jack Gilvey]

Stuffing the enclosure in no way DAMPENS anything!

Well, one of the definitions of dampen is to deaden, reduce, or lessen. So, stuffing/lining can dampen resonances/vibrations in the enclosure, technically. No?
Don't mean to get semantic, though.

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[Brian Bunge]

Jack,
Hell, you're right! Damn, that's one less thing for me to get pissy about now. I'm sure I can find something else, though!
Thanks again!
Brian
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[Patrick Sun]

Well, dampit!
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PatCave ; HT Pix ; Gear ; Sunosub I + III ; DVDs ; Link Removed

 

[Julian Data]

Brian,
Are you in a bad mood today?
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[Brian Bunge]

Julian,
No I'm not in a bad mood at all! Even though work's been hell the last week or so! I have this little joke I tell people all the time. I say that I'm not happy if I don't have something to bitch about!
I'm just looking forward to the weekend so that I can continue working on my dual subwoofer cabinets!
Brian
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[Julian Data]

OIC..
Dual Subs, eh? What drivers? Volume of enclosure, Fb.. etc.. ?
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[Brian Bunge]

Julian,
Yes, dual subs! Nothing spectacular. One SV12 each in a 3.4ft^3 sealed enclosure with it's own PSA1 200W plate amp in an external enclosure to allow amp upgrades later. They will also double as stands for my Emeralds and will be finished in the same manner. If I remember correctly the sims show an F3 around 30Hz. I'm hoping to get decent output down to 20Hz but I know it won't be anything like I'd get from a ported enclosure.
Later down the road I plan to add a 24dB/octave 200Hz crossover between the Emeralds and SV12's and then build a ported enclosure with the SV18 that will be a dedicated LFE sub.
I'm just looking forward to getting them finished! Moving these sumbitches around is exhausting!
Here's a picture of my Emeralds to give you an idea of what the overall finish will be:
Link Removed
Brian
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[Julian Data]

Wow! What's the finish on the Emeralds?
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[Greg Monfort]

Yes, bricks. You want something that's acoustically inert, and easy to add/remove.
GM
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Loud is beautiful, if it's clean

 

[Brian Bunge]

Julian,
I painted the Emeralds with a textured black paint and then used red oak on the sides with 4 coats of Minwax's Antique Red stain and two coats of polyurethane.
When I finish the subs (I still have to get a 1/4" beading bit for the grooves on the main cabinet) I'll be using an eggshell black paint instead of the textured stuff. I'm sick of spray paint. It takes too damn long to do and is too hard to get right!
Brian
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[Julian Data]

I am going the laminate route on my next set of speakers. - Yes, other than a sub!

Anyhow, I am having a difficult time looking for "light" cherry laminate as in the M&K Speakers.
Any tips anyone?
If I can't find any, I am probably going to dark cherry, oak or rosewood.
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