It's been a while since I've been researching about how to power up a car stereo without a 12 volt battery that I will surely have to recharge later. Why?
well....because I have a sony mp3 cd usb aux ipod-cable unit, 4x52w watts w/sub-out, what else could you ask for? I know, a nice set of speakers, right? I'm lucky to say that these speakers will be based on one set of sony 4 ohms 4 way drivers, another set of Boston acoustics 4 ohms 3 way, and one Miller&Kreisel; 8" sub. Besides the custom speakers building, I will perform the foam repair job to the sub and to one pair of Boston drivers, i'm working on a tight budget so... here we go.
Step 1: Stuff You Need
The second step is to gather the tools and items needed just to begin, it is not necessary to have everything at hand when you work on a project in the way I do, I only spent some of my free time, and I buy the things I need, this way I stay busy for a long. Yet there is nothing wrong with doing your project in one weekend but it can be frustrating and stressfull. Besides the fact that, when I start to do something I don't know exactly the way it will end, but the big idea is there, so I knew that my unit would ended mounted on a computer tower with a pair of "preview" speakers. So to start the tower, speakers and the atx power source are required the same as the drivers and stereo.
Step 2: Testing the Unit
Before we begin we must test that our stereo works properly when connected to the power source, here you'll find at least a couple of good INSTRUCTABLES on how to modify your power source to use it without the PC, the one I followed is "Convert-an-ATX-Power-Supply-Into-a-Regular-DC-Powe.pdf" This explains the key points to make this work, the most important thing is to link the green wire with any black wire, this way the source turns on automatically when plugged, and the other important thing is to sort all the wires by color, the important ones are: yellow 12 volts, red 5 volts, orange 3.3 volts and black is common ground, once this is done connect the unit's red and yellow wires( the yellow one is the cable that is energized at all times, and the red is the one that is energized at the accessory position of the ignition switch) , it is necessary that both wires are connected or else it won't turn on.
Step 3: Modify the Tower
So once we know that our unit is operating correctly, proceed to make modifications to the tower, always use your imagination, do not expect someone to tell you exactly how to do things, that alone will make you more numb.
Think, think and think again because once you cut it, it will be there forever, sadly I do not have a dremmell if I would've had one than the design might have been somewhat better, I used a saw and I struggled lot's to make the cuts, even so they weren't that bad.
I decided to install the unit in the center where the floppy should be, the top will be to keep things, is the size of a cd case, and the bottom will be my ipod station, control, usb and whatever may fit in.
Step 4: Mounting the Unit
Mount the stereo and start to make this look good, for it I use a thick cardboard that is used to create the background of some furniture, is easy to cut and sand, re-use your imagination and do it the way you want, for the top part I cut 5 pieces of cardboard to make a cube and glue it with plain glue, though they weren't near perfect size they were hold by pressure which facilitated the process of bonding. at the bottom I didn't use the same technique that was to have space for the ipod cable so I use one piece folded into 3 parts and screw it, I think this was the most difficult part, on top it I put a door using velcro you can do magic with it.
Step 5: "Preview" Speakers Installation and Basic Soldering and Wiring
Begins to extend the wires from the unit by soldering an extension, preferably using red and black colors wires to the speakers. Choose the proper place to install the speakers, use your imagination, they can be on the sides, top, front, bottom? however, the place where you decide to put them must have some holes to allow sound to flow a little better, remember that these speakers are not for a party, but are very useful when listening not loud music . I did the drilling of a similar size to those already in the tower, also added a double switch which allows me to use the speaker outputs with a worthy set of speakers, the switch of the image was replaced by another bigger with screws, the wiring is very basic switch has six poles one pair for input, and two pairs for output, ground wires (- black) must be linked together in pairs.
Step 6: Add the Extras
basically we have everything, just need to add the antenna, subwoofer outputs and spring clips, I will not add binding posts because they are more expensive and power is not that much. I tried to put an internal antenna, but it didn't worked there was no signal, so I add a car antenna, this way radio was enjoyable, the process is easy just plug the antenna to the stereo make a hole in the tower where you want to screw the antenna. For the subwoofer preamp output I bought a pair of rca to mount on a plate and mounted them on a piece of cardboard, make sure the rca don't not touch the tower or it will cause interference problems. Finally, for the spring clips use your imagination again, I mounted them on a piece of cardboard as shown in the images and adjusted it by pressure on the tower and finally with the Elmer's glue stix all, remember to weld all the pieces once you're sure about their position and operation. it would also be nice to add some extra support for the unit, and i forgot to mention that I added an array of leds that came out of a lamp they don't appear around here since this was a last moment modification lightning looks cool from the inside of the tower.
Step 7: Painting
Painting rocks, is my favorite part, no need to add lots of tape, just remove the unit and clean the tower, and start painting, color is a sweet black metallic, add a pair of extra layers to the cardboard.
Step 8: 4 Way Speakers
Be practical, I built this enclosure because I had already done a similar one before, the entire box is made of mdf, except the parts of the sides for this I use a thick cardboard some nail substitute glue which is very strong and flexible, the port is made of a sink tube, the pair of spring clips are very inexpensive and do not buy polyfill use pillow polyfill instead, the chrome bolts are there for appearance but it definitely has lot's of wood screws. Great sound, great treble and middle and good bass. obviously have to use a spring clip for each driver. finally sand, prime and paint...
Step 9: Boston 3 Way Speakers
I'm not going to write step by step how I did the speakers, because the Instructable How to Build Custom Speakers by noahw is just so sweet, so complete, that if you didn't got the idea with it, then you'll never will, but again I will say, use your imagination and be practical, I bought the BA735 speakers for $5 approximately, repaired speakers came in a truck that my brother had bought the front of the speaker box was from an old pair of speakers, the port is the same as the BA735, the I bought the crossover 50% off $6 The hole you see in almost perfect shape blue were made by a drill, the subwoofer is independent from the tweeter and midrange driver, follow the speaker repairing Instructable and make sure you're driver sounds near perfect.
Excellent crisp highs and really great mids and lows, the only problem is that both drivers are just to much for the unit, the volume needs to be really high and distortion levels seem to affect the drivers specially the sub else than that everything is perfect.
I'll let the pictures do the talking..
Step 10: Finally...
This was a good project to work with, the Miiler&Kreisel; sub that i mention at the intro 8" 50 watts i pay $4 for it and it only needed the foam replacement( payed $2 for foam), also have one klipsch center channel that cost me the same. I see so many instructables that work on a heavy budget, or destroy expensive stuff to create cheap stuff. This sub will power up my new little system, and belive me it is deep bass for such a little guy. Any quiestion i'll be more than happy to answer.