[keiko1fr]

Hi, to all the DIY sub, I am about to build my first sub. My spouse is with me at 100% for the noise but she is keeping a look at the $$$. I was looking at a vented box made by Rythmik Audio DS1500.

Woofer :Goldwood Delmar #GW-15PC/8.
Amp : Dayton SA240-B 240W.

Can you guys tell me about my choices ?.

about the finish of my box I would like to use the same technik used by Rodny Alvarez for css 10" project.
what is the different step used to end with such an incredible finish details are very welcome.

Thank you very much for your consideration

PS: I am a 95% movie, 5% music

 

[Mike P.]

The Goldwood is not a subwoofer for HT use with a Fs of 33 hz and an Xmax of 3.5 mm. State what your budget is for the sub and the amp, also state what the biggest size enclosure would be that's acceptable and we'll find a combination that meets your needs.

 

[ironglen]

Rodney's finish is VERY nice. And he has alot of experience and equipment (and it shows). I believe that a similar finish can be achieved using less effort, if you have the time to allow the finish to dry between coats. Not sure how well oil-based will dry in higher humidity air. I used rust-oleum gloss black oil enamel on my endplates and it is quite glossy even though I used cheapo foam brushes to apply only two coats, though mine is not quite up to his finish level, but I think it could be done if you use mdf instead of plywood, sand lightly between coats, and finish with more coats of polyurethane than just the single coat I used. That poly will give you the 'depth' I think you're wanting.

 

[keiko1fr]

my budget for both woofer and amp is about $300 to $400. For the enclosure I was looking at 18" wide x 24" deep x 25" high but I am open to every suggestion.

 

[Mike P.]

18" wide x 24" deep x 25" high would give a net volume of about 4.5 cu.ft. good enough for a ported 12" but too small for a 15" sub. If you want a 15" sub you'll have to reconsider your box size. How big of a room is the sub going to be in, is the room sealed or open to other areas? This will help determine how much "sub" you need.

 

[keiko1fr]

the room is open 13' wide x 20' long x 10' high ( ceiling ). Do you think 12" will be enough ?

 

[Mike P.]

Better to have too much then too little, a 15" would be better if you can handle the box size. That being said, the Shiva-X and a O-Audio Bash 500 amp would make an excellent combination. The sub is on sale for $149:

http://www.diycable.com/main/product_info.php?cPath=24_93_150&products_id=653

And the amp is $229 with free shipping:

http://www.oaudio.com/500W_SUBAMP.html

It would have excellent output for HT, 114+ db at 20 hz with room gain. Porting would require 2- 4" ports 35" long each, or a slot port which is easy enough to build.

 

[ironglen]

DIY has the ports on sale as well- just under $200 to your door for the driver and 2 ports, so ~$420 + enclosure and finish materials for that nice combo as Mike showed. You'd be hard pressed to find anything comparable for the price, I think.

 

[keiko1fr]

ok, about my box design what do you think ?, should I make it bigger ( Rythmik DS1500 vented). Or should I use an other design.

 

[ironglen]

ok, about my box design what do you think ?, should I make it bigger ( Rythmik DS1500 vented). Or should I use an other design.

Mike modeled the dimensions you stated for size with the Shiva and 500w amp- looks really good with extension to 20hz. If you're wanting to go deeper in hz you'd have to ante up serious enclosure size, driver size, and :spend: A comparable retail sub would cost you far, far more. If you have some woodworking experience and access to tools, diy is the way to go:T

 

[Mike P.]

18" wide x 24" deep x 25" high would work well with what I modeled above. The exact internal volume will depend on the added displacment of the sub, ports and bracing. Here are some calculators that will help you figure it all out. You'll have to use elbows to make the ports fit, the intake of the port must be 4" away from any wall. Or use a slot port.

http://www.hometheatershack.com/forums/enclosure-volume-calculator/

 

[keiko1fr]

ok

 

[Mike P.]

Post your final design when you're done, we'll make sure it's all good. :T

 

[Mario]

Better to have too much then too little, a 15" would be better if you can handle the box size. That being said, the Shiva-X and a O-Audio Bash 500 amp would make an excellent combination. The sub is on sale for $149:

http://www.diycable.com/main/product_info.php?cPath=24_93_150&products_id=653

And the amp is $229 with free shipping:

http://www.oaudio.com/500W_SUBAMP.html

It would have excellent output for HT, 114+ db at 20 hz with room gain. Porting would require 2- 4" ports 35" long each, or a slot port which is easy enough to build.

LOL, I was going to start a thread about this combo and then I see it's already being discussed. My concern is that O-Audio amp has a huge boost built-in in their SSF. Around 6db for 16Hz and 10db for 12Hz :yikes: I found some people complaining about it on other forums. I was thinking about tuning it lower and letting the boost compensate for the early roll-off, but I'm not sure how to simulate this correctly in WinISD. Any ideas on this?

 

[keiko1fr]

I will post some pics mike. I am about to order the parts

 

[Mike P.]

LOL, I was going to start a thread about this combo and then I see it's already being discussed. My concern is that O-Audio amp has a huge boost built-in in their SSF. Around 6db for 16Hz and 10db for 12Hz :yikes: I found some people complaining about it on other forums. I was thinking about tuning it lower and letting the boost compensate for the early roll-off, but I'm not sure how to simulate this correctly in WinISD. Any ideas on this?

The O-Audio amp also has a HPF at 20 hz with about 4 db of boost at that frequency. It works well with ported subs in the 4 cu.ft. range that are tuned to 20 hz. The effective range of the amp's EQ is 18 - 80 hz, the boost at 20 hz can be eliminated if required. In the modeling shown above there is 3 db of boost applied at 20 hz to "bump up" the low end.

 

[keiko1fr]

Mike, you told me that the Porting would require 2- 4" ports 35" long each, my original design was 2-4" ports 18" long each . If I add 2 extra ports at 18", my design should be 4 4"ports at 18" do you think I should be ok ?

 

[Mike P.]

Unfortunately no. 4 - 4 inch ports 18 inches long would tune the box to 38 hz.

 

[keiko1fr]

ok, i have no choice, i have to increase the size of my box. If i have to install 2 port at 35" long each

 

[Mike P.]

ok, i have no choice, i have to increase the size of my box. If i have to install 2 port at 35" long each

The ports displace .5 cu.ft., add .3 cu.ft for the sub and bracing. Your box should have a total internal volume of 5.3 cu.ft.