Home Theater Sub Woofer Selection/Design

[walt2]

So I am trying to design/build a sub for my HT (in the works, as of now only front L & R).

Below are my constraints:

*Budget: $200-300 (perfer to stay on the lower end, but will go higher if there is a signifigant improvement)

*Existing speakers: Front L/R Tritrix (first diy project)

*Yamaha HTR-3640 (may have wrong model #)

*Room size: 12' x 15' (Plan on moving to a larger house in +-2 yrs)

*70/30 (Movies/Music)

Below are my ideas:

* Dayton SD-315-88 12" & BASH 300w amp: At first I figured on putting this into a ported 5cuft box. Great price ($190)! However, size is undesireable.

*Dayton RSS265HF-4 10" & BASH 300w amp: More expensive (~$270), but in a ported 2.5cuft box, looks like this thing will go lower than the 12" above. I know a 10" is great for music, but will this make for an inpressive HT sub also? I really like the small box size, but it is more pricey (at least in compairson to the Tritrix I built).

*Dayton RSS315HF-4 12" & BASH 300W amp: If I am going for the 10" above, would it be worth it to just go ahead and get the 12"? A ported box with this thing would have to be ~5cuft ! So again, size is a bit large for my apt...but is it worth it? Will 300w be enough, or will I need to shell out for a 500w - 1000w amp (can not do now).

Let me know what you all think. I am trying to build something that will be both impressive, articulate, and will not overpower what I already have (or be turned down so low that it has a huge untapped reserve that I might as well built something smaller.

I went with a brand that I know, but new ideas altogether are welcome!

Thanks!!!

 

[Glowbug]

I like number #3

Just save the action movies for the weekends, to keep the neighbors happy

 

[chris661]

Go sealed, Linkwitz them. For movies, you can go as low as you like, because you'll never listen THAT loud...

For music, set the circuit to around 30hz and you'll be fine (you'll need 2 seperate circuits for this) - a simple switch in the input and you can set for movies or music.

300W will be plenty - remember - the difference between 300W and 600W is 3 decibels, which isn't a lot.

Chris

 

[walt2]

Go sealed, Linkwitz them. For movies, you can go as low as you like, because you'll never listen THAT loud...

For music, set the circuit to around 30hz and you'll be fine (you'll need 2 seperate circuits for this) - a simple switch in the input and you can set for movies or music.

300W will be plenty - remember - the difference between 300W and 600W is 3 decibels, which isn't a lot.

Chris

Chris,

Are you talking about going with the 12"HF?

I was going with the ported theme because everywhere I look, people say ported is best for HT. I like the sealed idea because of size and simplistic build. On WINisd, ported shows both the 10"HF and 12"HF flat at around 20hz, where sealed does not go flat until the mid 30's. Is that a noticable difference? (I am new to this and not entirely sure how to interpret the graph)

Thanks for the advice!!!

Walt

 

[Glowbug]

I use my single sealed 12" for both movies and music, and I think it does a great job for movies - but my ratio is more like the exact opposite of yours.

If I were building something for your needs, I'd probably want to go ported.

 

[walt2]

I use my single sealed 12" for both movies and music, and I think it does a great job for movies - but my ratio is more like the exact opposite of yours.

If I were building something for your needs, I'd probably want to go ported.

Jim,

Thanks for your input! Going sealed has always been in the back of my mind, and move into a ported box when I move into a bigger place. Regarding size, do you think there would be a sizeable difference between going with the 10" ported and the 12" sealed (about the same size box)?

I could go sealed with the 12"HF now and build a big ported box when I get a bigger place.

Thanks again for your help!!!

 

[chris661]

You can go with any you like - for Linkwitz, you'll need more power handling and displacement (either a 10" with loads of Xmax, or a 12")

The idea is that, when you get rolloff on your sub, the amplifier will put in the opposite (ie, boost the frequencies) so the response remains flatter for longer. For example, I have a sub using a pair of 8" DVC woofers. In the box I made, they'll go pretty low (-10dB point at 40Hz, boosted with room gain gives something better), with the circuit, 28Hz (-3dB). The sacrifice is how loud you can go. Remeber - you can't have deeper bass for nothing.

Chris

PS - this'll help your understanding.
http://sound.westhost.com/linkwitz-transform.htm#power

 

[human.bin]

if you are undecided beetween ported or not maybe this is worth a look

Creative Sound - Product Details

i was considering this for a friend when i stumbled in your thread i'm really not an expert

 

[chris661]

Passive Radiator design - used commonly for HT by manufacturers such as KEF.

 

[walt2]

Thanks everyone who has lent me advice so far!!!

So, the more I look into the actual woofers to use, I am sensing that I will be less than satisfied with a lower end driver such as the Dayton SD-315-88 12". Am I wrong for this assumption? Plus, I can not find anyone else who has built a sub with it (not that I want to copy ideas, but I like to learn from others experience).

So I am now leaning towards the 12"HF, possiably in a sealed box (I am afraid that a ported box may be a little too loud for my apartment and the passive radiator is completely foreign to me; being my first home sub build, I want to keep it as simple as possible). Plus, I feel that this driver will hold it's own when I move to a larger place within the next couple of years.

But, just for kicks... what do you all think about this...

I figure I am stretching my budget by going towards the 12"HF; but while I'm at it, for only about $20 more I could get the 15"HF Parts-Express.com:*Dayton RSS390HF-4 15" Reference HF Subwoofer 4 Ohm | subwoofer rss390hf-4 15" subwoofer dayton reference rs sub dayton loudspeaker. Looks like for a sealed box, 4-5 cuft will be good. Would this work well with the BASH 300? Is this overkill for my intentions? Never had experience with a 15" before, are they suitable for both music and movies, or do they just go boom boom?

Thanks again all!!!

Walt