2 subs in sealed vs 1

[Guiria]

Do you realize any benefit from 2 subs in a sealed box over 1 sub (using the same amplifier)? Both boxes would have a Q of 7.0? The dual sub box would have the drivers facing opposite each other.

 

[annunaki]

Dual subs with the same amount of power would have a +3db advantage as the surface area is doubled. If the power is increased accordingly you would/should see around a +6db increase. Using two sub woofers in sealed enclosures will not deepen response, but only make the system louder.

What exactly are you trying to accomplish here? What is your intention?

I would hope the "Q" would be .70 and not 7.0

 

[Guiria]

I would hope the "Q" would be .70 and not 7.0

right you are, my bad.

To start - all mentioned speakers are/will be going in a 12'x13'x8' bedroom. This system is currently for 100% music. General listening position is about 8 ft from the bookshelf speakers.

I've recently built a pair of bookshelf speakers using a 3 inch driver in a ported box tuned to 70 hz. While they sound great within their design goals, any music with lower frequencies brings on audible distortion in the speaker.

I have a pretty tight budget to build a sub ($100 for amp + sub) and add some low end. I plan on purchasing the Dayton SA70 - 70 watt amp and I want to find a sub to go with it.

Dayton's DVC 8" inch sub is cheap enough for me to buy 2 of them if any real benefit would be realized over a more expensive 8" model. Extension below 40 hz is really all I'm after.

Based off of Annunaki's statement I am leaning away from 2 subs in a sealed enclosure if the primary benefit is output...this system will most likely never see reference level.

I've been looking at 8" speakers given the amount of power that will be available...if a 10 or 12" would perform well with 70 watts then that would certainly be an option.

That's enough for now.

 

[annunaki]

I would look for a highly efficient and sensitive 12" or 15" woofer and place it in a ported enclosure. It will yield the greatest output with the least amount of power.

$100 is a pretty tight budget for the whole sub. How much is the amplifier? What is left over for the sub???

 

[Guiria]

Amplifier is $45.00. Leaving $55 of original budget I can probably round up another 20 or so but not much more than that. I already have 3/4 mdf, glue, tools etc to build the box...just need the essential components now.

I'm half tempted to hold off on the bedroom sub until I have some more funds to build a sub that will replace my Velo VX-10 up in my TV room. Then I can move the Velo downstairs to the bedroom and have something kick butt upstairs.

Currently my Velo is trying to do the job in a 15x19 bonus room and it struggles with LFE quite a bit in a room that size.

 

[annunaki]

That sounds like a pretty good option to be honest. Why waste money on a stop gap that will be replaced potentially anyway. It will also give you that much more towards your "real" sub for the bonus room.

If you can't resist here are some options that will work even if slightly underpowered:

12" http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=295-555

12" http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=295-490

15" http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=295-470

10" http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=264-862

10" http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=295-485

10" http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=295-550

If I have some time, I may model a couple of my picks for you and let you know the verdict.

 

[Guiria]

I'll have to take some time and model these drivers as well in WinISD. I would be interested in your findings if you get around to it.

 

[annunaki]

I modeled a few last night with not the best luck. I don't know what it is but the only Dayton drivers that model well are the High Fidelity and the Titanic. The enclosure for the 15" was over 10 cu. ft. I will do some other when I have some time. I started to fall asleep while doing it last night.

So far the 12" quattro looked the best.

I have not gotten to the 10" drivers yet.

 

[annunaki]

See if you can pick up a used JL Audio 12W3-D2 or 12W3v2-D2 on ebay for $75.00 or less.

Otherwise try for a 12W1v2-4. They would do very well in your application and run well with fairly low power.

http://cgi.ebay.com/JL-Audio-Speakers_W0QQitemZ260172859829QQihZ016QQcategoryZ18803QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


This is a steal.

the JBL GTO1202D is also a good performer.
http://cgi.ebay.com/JBL-GTO1202D-CAR-12-SUB-WOOFER-DVC-2-OHM-GTO-NEW_W0QQitemZ150173058841QQihZ005QQcategoryZ18803QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

[Wafflesomd]

You should use 18".

I have all my PA gear sitting in my room for storage. I also use it for my source of music at home.

Four 18" Scoops and two 18" reflex bins. Four Yamaha Club V's on top of that. I think it sounds better than my DIY Daytons. Keeping in mind I play it all at low levels in my house. Just because you have all that power doesn't mean you have to turn it up all the time.

I used to use a 12" Dayton Sub. I like the 18's better. They go much, much lower.

 

[Guiria]

I modeled a few last night with not the best luck. I don't know what it is but the only Dayton drivers that model well are the High Fidelity and the Titanic. The enclosure for the 15" was over 10 cu. ft. I will do some other when I have some time. I started to fall asleep while doing it last night.

So far the 12" quattro looked the best.

I have not gotten to the 10" drivers yet.

I noticed the same in some of my modeling...those Dayton subs require huge amounts of airspace which definitely will not work in a bedroom, I will hopefully have some more time to model subs tonight.

I echo my previous thoughts which are even more convincing now...perhaps I'll just wait till I can build the titanic or HF sub, or even an IB

 

[Wafflesomd]

I noticed the same in some of my modeling...those Dayton subs require huge amounts of airspace which definitely will not work in a bedroom, I will hopefully have some more time to model subs tonight.

I echo my previous thoughts which are even more convincing now...perhaps I'll just wait till I can build the titanic or HF sub, or even an IB

They have low QTS. The box shouldn't be any bigger than a normal sized 12" or 15" sub box would be.

 

[annunaki]

The response curves on the dayton drivers in question are very peaky. Not even close to what one would desire in a sub system. Perhaps in the car they may do well?

 

[tomd51]

The SQ10 driver from Elemental Designs has generated some favorable feedback for a relatively low cost and small profile. This post from ED's forums may be of some interest that's related to using this driver in an HT setup, though the enclosure is pretty honkin' for use in a bedroom. Nevertheless, you could likely come up w/a decent enclosure using WinISD that would be more suited to your needs.

I've also made this post over at the HTS recently that may be of some interest, though the referenced drivers are a bit more than you're looking at. Even so, I've found them to be are excellent performers for the money... -TD