Outdoor 3-Way Speaker Sound System 12V

This is a active speaker construction that works on a 12V battery. The speaker gives you the opportunity to throw a party on any given location.

The first part of the instructable consist of making the speaker box. The second part consist of installing the speakers and the amplifiers.

http://blog.wdka.nl/make/2008/05/13/joris-mobilesoundsystem/

Step 1: Size of the box

To determine the size of your speaker boxes you got to have the speaker drivers. For the material of the speaker box best use MDF, it's heavy but relatively cheap and it has a high level of density which makes it perfect for speaker boxes.

You also need some screws, nails (optional), glue, a filler to stuff the box with (like polyfill) and silicon to seal the edges.

For tools you need a saw, screwdriver, centimetre, a drill, compasses and a jigsaw.

I split it into two boxes; one for two sub woofer speakers and one for three woofers and two tweeters.

To determine the size of your boxes check the optimal volume and displacement for each driver. For the two 15 inch sub woofers I use a case os 92 by 65 by 40 cm (internal dimensions) For the other case I use 92 by 65 by 30. The MDF I use is 15mm thick.

Comments

[rburton1]

ten minutes ,at max party level....you would need 6 batterries .and 2 chargers to keep batteries going ..ive been there and done that ..nice idea but.....

[gkirkby]

Not true my friend, inless you use terribly inefficient amps and inverters.
6 hours out of one leisure battery including lights is standard.

Get yourself down to the next 12v teknival in Bristol,
since the police have no problems with 12v free parties...

[bumpus]

That looks really professional, i would buy it :D

[groovy]

You guys have all lost it

[Handsome-Ryan]

I like what you built, the craftsmanship is fantastic, but your instructable is lacking many important details. I respect what you built but since this is instructables, I'll offer some tips that may benefit others who want to use car audio equipment outside of a car. First, it is important to note that car audio devices were designed to run off the current from a car's alternator NOT a car's battery. Unless you invest in a deep cycle battery, this regular cycle of charging and discharging will ruin a standard car battery very quickly. Next, in step 7 you completely breezed over calculating the resistance of speakers when using more than one per amplifier output. People attempting to replicate this should be aware of what resistance their particular amplifier is capable of handeling and if you wire speakers to run lower resistance you increase power draw and will discharge your battery much faster. Finally, it is not usually a good idea to put amplifiers inside speaker boxes because there is not enough air flow and the amplifiers give of a lot of heat that needs to be disapated. I would sugest mounting the amps to the outside of the boxes rather than the inside to avoid putting them all into power-protect mode just as the party is getting cranked up. Other than that, I'm very impressed at how well constructed your boxes are and how clean the finished product is. Very nice.

I recently built a miniature version of something similar to this (one amp and two 6.5" speakers) as part of a trailer mounted bicycle stereo.

Stereo Trailer Pic

Trailer Pic 2

[xana]

Just to say there is a lot of air flow in the two boxes because of the mid-range and sub-woofers. but i do agree that it would drain the battery vary fast.

[Sandisk1duo]

just get a car battery charger, and run the amps while you're charging the battery, it shouldn't make a difference (kill your battery) if you do that

[Lurch]

Kind of defeats the '12V' aspect of it then does it not? You need more than a standard battery charger to make sure it works like that anyway. Most battery chargers will throw out around 4A peak, not enough to keep the battery topped up all night and definitely not enough to keep the amps running as well as charge the battery. You may as well do away with the battery and build a decent fixed voltage power supply, or use a better set of batteries that don't need a charger sat on them all night.

[Sandisk1duo]

i have a charger that can put out 40 amps, and a couple seconds of 100amps

[Lurch]

Well, I didn't say it was impossible, just not practical to. It's generally best not to use car battery chargers to power devices anyway.

[slimguy379]

why do u have the same gauge wire for the remote as you do the power? any specific benefits?

[baneat]

Maybe you should consider some of those strong mesh covers for the drivers so people can't poke holes in them..

[DIY Dave]

Where do they sell mesh covers for speakers?

[baneat]

You're on a DIY site, come on. really? they would be very easy to make.

[hg341]

how would I go about make a backpack one with the same power or would it be to damn heavy

[bobmcbob_345]

You should make a place inside the cabnets to put the 12 v battery in. It could help save a little space

[hell_raiser_1]

How about adding a usb, ipod, cd, car stereo. you could also add a power invertor or something like that... NICE WORK

[Henkies]

How long does it run, following your experience?

[Handsome-Ryan]

How are you using Ohms law to calculate run time? There are so many factors affecting run time including amplifier gain settings, ambient temperature, the non-linear discharge rate of the battery, and even the volume and type of music being played.

[Sandisk1duo]

get an amp meter, play music for a muinute, check how many amps are drawn, then TRY to calculate

[i8_power_shooter_18]

Hey bro that is awesome.If u could give me a little help with something im a big bicycle rider an i want a stereo system for my bicycle odd tho it would be awesome lol.I got a mp3 player id like to use along with a few speakers nothing big as the ones that u got lol.Could u tell me what wiring or amp or just what i would need i want it to have good bass if u would please give me a email on [e-mail] or just on here or anybody knowing what i need to do this thank you.

[Sandisk1duo]

just get computer speakers, and power them with an RC car battery

[DIY Dave]

Very professional looking

[pepitosbazzeguti]

Great work........Is this system good for music instruments too ?

[abadfart]

or i could put it in a trailer so we can use the truck for the drums

[abadfart]

nice can you run a guitar through it maybe my friend and i can mount speakers on Thelma (his truck) or in my car for shows

[sinous]

Information is wide ranging and a good start. My only issues are a) Impedence and wiring - more info/? eg bcae1.com b) Running time - how long? c) Using car woofers off a car battery - what about using a pro 15" which will be about 9dB louder for the same power(less low bass though)-giving you longer run time. This is where u can get alot more out of the same battery - being louder to start with - not by adding bigger amps. d) How to charge(without ruining battery) *SPL: 97 dB 1W/1m

[DJNASHA]

i love it .i wish i'd seen this sooner be for i started my d.j biz keep it coming make more bro

[thefreshlettuce]

How much did this cost? It looks fantastic!

[slimguy379]

yes very cool but I too would like to know how much this cost because this seems quite expensive because you have 3 amps- $30 (that's a steal for car amp!!!) mdf at least 6 sheets of mdf - $8 and the speakers look new so.... Well I'm not going to try to put a price tag on 5 huge speakers. but then again you made the thing so I'll let you explain the price issue

[paprika killer]

my guess will be between $120 and $175.