DIY Subwoofers - UPDATED

[iamwiz82]

My goal is to build a low cost subwoofer for my home theatre. I need some help, however. I want to keep the costs to ~$100 for everything and I know very little about home audio components.

Whats a good driver?

Can anyone point me to a good electrical schematic for the innards?

So far my plan includes:

3/4" MDF box
Wooden poles for bracing
Some R-13 insulation, carpet padding, and roofing felt for stuffing

Basically, all I need to buy is the MDF, the pole (I think a closet pole will do fine), the nail (regular and liquid), and the electrical gizmos.

What exactly is needed to wire a 12" subwoofer to a Sony Reciever? I have a RCA out from the reciever.



UPDATE: Well, it's roughly done! For reference, it's a 40" piece of 18" diameter sonotube, with MDF ends, two ports, with a 12" Pyramid driver.

Total cost: $107, including hardware.

It's rattling my house away already

My next plan is to finish it alittle nicer with a wood finish. It will end up living between our couch and wall, so it's not going to be seen, but hiding it from Lola's eyes is a concern .

 

[us3rnotfound]

i farted

 

[T3C]

good luck.

 

[Kaido]

You want to start at Parts Express.

What size driver do you want to use?

 

[iamwiz82]

Originally posted by: Kaido
You want to start at Parts Express.

What size driver do you want to use?

12"

 

[sohcrates]

you cannot run a sub off your receiever. you will need some type of separate amplification. you can use the sub line out to drive the external amp

 

[iamwiz82]

Originally posted by: sohcrates
you cannot run a sub off your receiever. you will need some type of separate amplification. you can use the sub line out to drive the external amp

I assumed this, what kind of hardware is available for something like this? Would I simply use a normal amp or are there specialized ones for what I am trying to do.

 

[YOyoYOhowsDAjello]

This sub goes on sale for $99 once in a while. I think it would be very hard to beat it building one yourself.

If you want more info on DIY, check out the DIY area of AVSforum. There are plenty of other sites on it too, but I haven't looked into them much.

 

[Kaido]

Originally posted by: iamwiz82

Originally posted by: sohcrates
you cannot run a sub off your receiever. you will need some type of separate amplification. you can use the sub line out to drive the external amp

I assumed this, what kind of hardware is available for something like this? Would I simply use a normal amp or are there specialized ones for what I am trying to do.

There are specialized ones. Basically there are two types of subwoofer amps: integrated into the sub and external. The integrated ones are called plate amps, like you see on most subwoofers, such as Logitech subs. You can also get an external one, such as a monoblock amp. You can do other things too such as use a regular amp and do different wiring schemes but for what you're doing a plate amp is probably the best way to go.

 

[sohcrates]

Originally posted by: iamwiz82

Originally posted by: sohcrates
you cannot run a sub off your receiever. you will need some type of separate amplification. you can use the sub line out to drive the external amp

I assumed this, what kind of hardware is available for something like this? Would I simply use a normal amp or are there specialized ones for what I am trying to do.

my suggestion would be some type of mono aplifier. i've seen them sold in places like tweeter etc. usually the point is to buy 5 of them to make your own home theater setup, but one would work. of course, they run around $200 a pop.

it's *definitely* cheaper to just buy a pre-made sub with an amp.

i had several friends build their own sub / amp combos, but building an amp from scratch requires mucho knowledge and patience and testing

another one of my buddies tried to run a sub off his home receiver (without a crossover) and all the fuses in the amp blew within a few minutes.

 

[Slvrtg277]

Originally posted by: Kaido
You want to start at Parts Express.

What size driver do you want to use?

Another vote for partsexpress. Check it out.

 

[radioouman]

Only one nail?

 

[iamwiz82]

Originally posted by: radioouman
Only one nail?

Yes, but it's a big effin' nail

 

[iamwiz82]

I have read that home and car subwoofers should not be used in the other application. Is there a way of telling which is which?

 

[YOyoYOhowsDAjello]

Originally posted by: iamwiz82
I have read that home and car subwoofers should not be used in the other application. Is there a way of telling which is which?

You can do it if you want to afaik. Just make sure the impedence matches what your amp can handle.

 

[iamwiz82]

I'm looking at plate amps now. Would I just run an RCA on one side and the normal bare wires on the other?

 

[lancestorm]

I run rca to rca.... rca subwoofer preout on receiver to plate rca input of sub

 

[YOyoYOhowsDAjello]

Originally posted by: iamwiz82
I'm looking at plate amps now. Would I just run an RCA on one side and the normal bare wires on the other?

Well, I think you'd want them to be insulated

I just wanted to point out one more time that with that dayton 10" sub you're getting a 100watt amp and a $20-ish driver plus a nice enclosure for $125 before shipping (and $99 or $109 if you wait for a sale). I got mine for $109 and was quite impressed with it for the cost.

I wanted a little more though, so I ended up selling it, but they guy I sold it to really likes it too.

EDIT: oh, for the wires question I thought you were asking how to set up the receiver to amp connection and then the amp to driver connection. Yeah, RCA on both ends for receiver to amp connecion.

 

[iamwiz82]

Originally posted by: YOyoYOhowsDAjello

Originally posted by: iamwiz82
I'm looking at plate amps now. Would I just run an RCA on one side and the normal bare wires on the other?

Well, I think you'd want them to be insulated

I just wanted to point out one more time that with that dayton 10" sub you're getting a 100watt amp and a $20-ish driver plus a nice enclosure for $125 before shipping (and $99 or $109 if you wait for a sale). I got mine for $109 and was quite impressed with it for the cost.

I wanted a little more though, so I ended up selling it, but they guy I sold it to really likes it too.

Part of the fun is doing it myself. I enjoy this kind of thing. I grew up with Legos and now I am on to bigger and better (more expensive) things.

 

[Kaido]

Do the following two things as well:

1. Google for "diy subwoofer" - there's a lot of good resources and designs available with pictures.

2. Go sign up at the Parts Express Tech Talk forum. link Tell them the same thing you posted here, along with the size you want, and you should get some great help within a day or two.

 

[YOyoYOhowsDAjello]

Originally posted by: iamwiz82

Originally posted by: YOyoYOhowsDAjello

Originally posted by: iamwiz82
I'm looking at plate amps now. Would I just run an RCA on one side and the normal bare wires on the other?

Well, I think you'd want them to be insulated

I just wanted to point out one more time that with that dayton 10" sub you're getting a 100watt amp and a $20-ish driver plus a nice enclosure for $125 before shipping (and $99 or $109 if you wait for a sale). I got mine for $109 and was quite impressed with it for the cost.

I wanted a little more though, so I ended up selling it, but they guy I sold it to really likes it too.

Part of the fun is doing it myself. I enjoy this kind of thing. I grew up with Legos and now I am on to bigger and better (more expensive) things.

Alright. I just wanted to let you know that the dayton is a heck of a deal. Have fun

 

[iamwiz82]

Originally posted by: Kaido
Do the following two things as well:

1. Google for "diy subwoofer" - there's a lot of good resources and designs available with pictures.

2. Go sign up at the Parts Express Tech Talk forum. link Tell them the same thing you posted here, along with the size you want, and you should get some great help within a day or two.

I've seen stuff on google regarding it, but most of them aren't very good, IMHO. I have read ones where they go on for 15 pages on the design of the box and then spend half of a paragraph on the amp portion.

 

[thomsbrain]

Originally posted by: iamwiz82
I have read that home and car subwoofers should not be used in the other application. Is there a way of telling which is which?

it doesn't matter, a woofer is a woofer. but some woofers are designed to be used in certain sized boxes (or no box at all), so as long as you're taking that into account, the woofer doesn't know where it is and won't suddenly blow up because it's in your living room and not your car.

 

[Kaido]

Originally posted by: iamwiz82

Originally posted by: YOyoYOhowsDAjello

Originally posted by: iamwiz82
I'm looking at plate amps now. Would I just run an RCA on one side and the normal bare wires on the other?

Well, I think you'd want them to be insulated

I just wanted to point out one more time that with that dayton 10" sub you're getting a 100watt amp and a $20-ish driver plus a nice enclosure for $125 before shipping (and $99 or $109 if you wait for a sale). I got mine for $109 and was quite impressed with it for the cost.

I wanted a little more though, so I ended up selling it, but they guy I sold it to really likes it too.

Part of the fun is doing it myself. I enjoy this kind of thing. I grew up with Legos and now I am on to bigger and better (more expensive) things.

I hear ya dude! Speakers = Legos that actually do something I'm building my first set of speakers right now and I'm having a blast.

I did a quick search on PE. I don't know if this stuff is any good, but take a look at the following:

12" woofer for $30
70w subwoofer amp for $50

I don't know how good those two are, but do some googling and see if they've been used in other people's projects. That's $80 right there, then buy your wood and whatnot. Sub says 80 watts with 115 max, so it should be fine with a 70 watt. I'm no sub expert tho, try PMing ribbon13, he knows a whole heckuva lot about subs and speakers

AFAIK, you just hook the inside of the amp to the driver with heavy-gauge speaker wire. No crossover required internally, like speakers. Then you just run a single RCA subwoofer cable (I think they're usually 75-ohm cable/connectors with heavy shielding) from the sub pre-out on the amp to the plate amp on the sub.

 

[iamwiz82]

I noticed that the palte amp has two RCA Inputs. Does it matter which one the Sub-Out runs into?