$100 garage subwoofer?

I'm redoing my garage (workshop) and looking to add some bump. I will have a Sonos zone out there, but I'd like to build a subwoofer to go with the main speakers.

Is it possible to build something reasonable for about $100, not including amp? I can just use the crossover in the Sonos and I can get an amp (if I don't already have an extra somewhere) for free/cheap.

I'm completely redoing the garage so I can do in-wall subs, something up in the rafters (no drywall in ceiling), etc. I can get creative. The driver will be the biggest expense I assume. Any ideas? I've been looking around and I don't see people adding subs in their garage much. It can be big, it can be ugly...
 
Is it possible to build something reasonable for about $100, not including amp?

Define reasonable.

A single sheet of quality plywood will cost about $50, leaving about $50 for a driver, glue and any shop supplies and tools you might need.

So it isn't going to be big or loud, but it might be ugly since there's nothing left in the budget for any kind of finish.
 
reasonable? well, it's an adjective...

kidding.

I'm sure a sub could be built with a 6" driver salvaged from an old pair of bookshelf speakers, and put into a cardboard box and spraypainted for $20, but it will sound terrible and won't be worth using. I guess that's what I mean. I can't really qualify my level of expectation, but I do own nice stuff in the house (my main speakers are Dali Helicons). I just want decent bottom end, but I'm not expecting anything too amazing.

I have plenty of shop tools (anything I'd need to build a sub at least). I even have a 75-watt epilog laser cutter 20 feet away from me right now, and a stockpile of acrylic if it comes to that. Cost would be strictly materials. I have wire, glue, etc. I even probably have some banana jacks sitting around.

does that help? I've just never really heard a $50 driver in an ugly unfinished enclosure before to know what to expect...
 
You have enough money for one driver and one sheet of wood. There's a lot of different ways you could go with that.

Check parts express buyouts and maybe mcm for affordable drivers and it probably makes sense to used a ported box for maximum bang for the buck. If you choose a smaller driver you can do a tapped horn instead.
 
cowanrg,
You can make a perfect setup (only my idea), other members can help you with different setups and available budgets.
Do you have a mono out or a stereo out, plus amp?! Well, if one (it's a DVC), connect the voice coils (VC) in parallel. If two (outputs/stereo amp) connect to the two voice coils of the dual sub.
Going to the budget section of drivers (you can also look under specials, discount or rebates) at PE (or Madisound), I found this nice subwoofer driver for you, priced at the moment for $29.65.
Dayton Audio SD215A-88 8" DVC Subwoofer 295-484
It goes in a (ideal) bass reflex enclosure (BR) of internal dimensions 37L / 1.30ft³ (Vb) and needs a tuning frequency of ~26Hz (Fb). It goes really low under [email protected] and has an F3dB = 38 Hz.
Important, there are also instructions for "" OPTIMUM CABINET SIZE *"", use my/diyAudio forum dimensions and instructions.
For this you need to add the port total volume (+driver) to the enclosure, that you can buy or can be made from a plastic pipe, or wood (square) by you (~4.5L / 0.15ft³).
If you need the dimensions for a port to have an idea, is about 7.5cm / 3" and length needs to be adjusted or tested around to 47cm / 18-19".
With this driver you will need a 80/90W [email protected] for max output at Xmax.
Have fun and report results. :)
 
Einric:

that's more what I was thinking. I wasn't really thinking of building a standalone 'box' subwoofer. I was more thinking of building it into the garage, using some stud bays, etc. I don't mind re-drywalling and such. I've read the legend of el-pipe-o, but it's been a LONG time ago.

Inductor:

I like this idea. I could easily do 2 of those, add an amp, boom!

I looked around and I have a couple different amps I could use. I have a couple stereo 200WPC ones I'm not using. One is an older ICE amp, the other is something from International Rectifier. Stereo or mono signal, no problem. The Sonos has a dedicated sub out (adjustable crossover), or I can just use the line-out, either one.
 

Einric

Member
Paid Member
2011-02-26 2:12 am
Bozeman, MT
You could mount the sub in the bottom of the stud cavity and create a hole at the in the top of the cavity at the 1/4 wavelength of the FS of the chosen woofer.
Many 10" DVC Car Subs from Diamond Audio have FS in the 40's that would put your port about 6 feet up the wall.
After that just stuff it to taste.
 
Hi cowanrg,
Just one more: the Infinity 1262W is often on sale: e.g.:
Amazon.com: Infinity Reference 1262w 12-Inch 1200-Watt High-Performance Subwoofer (Dual Voice Coil): Car Electronics
add some OSB, and Hornresp, and you are all set. :)
Regards,

Yes that infinity sub with a $30 scosche enclosure
Scosche SE12CC Subwoofer Enclosure, 12": Auto Electronics : Walmart.com

and the remaining $10 for a grill from ebay/amazon and some fibre glass wool(only for sealed) from home depo.
 
Braces and braces

Yes that infinity sub with a $30 scosche enclosure
Scosche SE12CC Subwoofer Enclosure, 12": Auto Electronics : Walmart.com

and the remaining $10 for a grill from ebay/amazon and some fibre glass wool(only for sealed) from home depo.
I have a pair of Infinity 1262W's in 73 liter boxes and am feeding them with a Cerwin Vega CV-900 into the 2 ohm (paralleled coils).
That is 420 W/channel if you believe all the data sheets.
They are mean, nasty, angry (that's good) woofers.
I have them running in a sealed box (I built subwoofers and just needed woofer cabs) and they have an in room rising response down to 35 Hz, but then drop like a rock, lower F3 than I would expect but they are in concrete corners with both walls and floor concrete.
.
Anyway, my point is I had to go back and add bracing to the cabinets with 2-1/2" wide 18 mm Baltic Birch "studs" about 10" on center all around the box, top to bottom.
I doubled the baffles with 18 mm BB as well as adding a second layer on the bottom to cover the old 4" port hole and a second layer on top to help support the pole kits that I am flying my tops on.
I also put 2 sections of 1" oak dowel rod to try and tie the top to the bottom.
I think I used a half pint of Urethane glue on these.
And, they really still need more bracing.
.
So, what I am saying is if you buy a low cost box and plan on putting any decent amount of power into them, brace the boxes really well.
They will rip cheap boxes to shreds.

Good luck, have fun
Dave
 
garage speakers

I designed a horn system for a good friend. The bass horn is the plywood unit in the corner. (see attached picture) The driver and compression chamber are on the floor at the bottom. The throat starts at the comp. chamber and the hypex. horn goes up the corner, folds over at the ceiling , comes back down and the mouth is back at the floor, aiming into the garage. Two mid range horns (30" dia. round tractrix) and two tweeters (MCM Electronics) complete the system. The bass horn really makes the system. That's the important one to build.You could probably use inexpensive "box" speakers for the midranges and tweeters, but nothing sounds like the total horn system. My friend used a 15" driver for the bass horn and had about four sheets of 3/4" plywood invested. You could down size to an 8" driver and end up with a much smaller(less expensive speaker), but It would still sound very good.
 

Attachments

  • Ray's pictures 067.jpg
    Ray's pictures 067.jpg
    144.5 KB · Views: 93
You could mount the sub in the bottom of the stud cavity and create a hole at the in the top of the cavity at the 1/4 wavelength of the FS of the chosen woofer.

With 4 of these woofers each in their own stud cavity you could Series+Parallel them for a nominal 6Ω load and about a 95db sensitivity.
4 12" woofers would ROCK a garage.

I would be very wary of putting drivers in stud cavities. Especially a bunch of large, powerful woofers. These spaces are never well sealed, the back of the cavity is usually drywall, and large woofers will shake the whole wall. So you'll need a case of caulk to seal it all up, you'll need to beef up the construction on the whole stud cavity, and no matter what you do the wall is going to vibrate so it's going to make it's own noise - and you better hope there's nothing loose anywhere inside any of the wall cavities or it's going to rattle.

This is exactly the reason that manifolds decoupled from the wall are preferred in IB construction, all these problems are bypassed.
 
I designed a horn system for a good friend. The bass horn is the plywood unit in the corner. (see attached picture) The driver and compression chamber are on the floor at the bottom. The throat starts at the comp. chamber and the hypex. horn goes up the corner, folds over at the ceiling , comes back down and the mouth is back at the floor, aiming into the garage. Two mid range horns (30" dia. round tractrix) and two tweeters (MCM Electronics) complete the system. The bass horn really makes the system. That's the important one to build.You could probably use inexpensive "box" speakers for the midranges and tweeters, but nothing sounds like the total horn system. My friend used a 15" driver for the bass horn and had about four sheets of 3/4" plywood invested. You could down size to an 8" driver and end up with a much smaller(less expensive speaker), but It would still sound very good.

that's pretty darn cool, but takes up WAY too much room. nice project though