Car MP3 Player
The computer you're going to use can be a piece of junk. I've found that the perfect computer for this project to use was a Pentium 75mhz with 8 megs of ram. I used a 540 meg hard drive for this project, but I'd suggest at least 2 or 3 gigs. (All depending on how much music you want to load onto it at once) If you're planning on getting your mp3's from a cd, or network, then a simple ancient 50 meg hard drive will do just fine. (I have a box full, and I'll sell you one for $5)
Your computer should have a sound card. If it doesn't already, you don't need a fancy one, but make sure it's 100% Sound Blaster compatible. (Other cards that work well are "Windows Sound System", and "Ensonique". This is especially necessary for this, because you will be running your computer in dos, and it's hard to find dos drivers for anything other than a sound blaster. In most cases, the better the sound card, the better the sound, but when it comes to something as simple as this, this is not always true. I'm using an Ensonique Soundscape 16bit ISA for this (about 9 years old), and it sounds just as good as any newer cards or anything else I have laying around. (I don't have a sound blaster live to compare it to, but I bet it'd be about the same) Just make sure the sound card is 16bit, stereo.
One last thing to consider, is size. Chances are, you're going to want to install this in the back seat, or the trunk. Keep it small. Also, check the power supply rating. Try to keep the power consumption under 200 watts, and NEVER go over 300. See the power section below for more info.
Before we continue, I'll assume your sound card is already installed, and your hard drive and all your other stuff is in. If you have any extra stuff in there you don't need, take it out, so you can use it in another computer. Remember, this is going to be just an MP3 player, nothing more.
Check out your computer, and see if it will boot up without having a keyboard plugged in. If it does, great, if not, you've got a choice. 1: have a big clunky keyboard laying around wherever you stick the computer, or 2: put the circuit board from the keyboard inside the computer somewhere. . . . .
Find the cheapest, junkiest keyboard you can find. (One that you don't need anymore, and that is somewhat (10 years) recent) Open it up somehow, and you should see a small circuit board, with like a thing that goes to the rest of the keyboard, Unhook the rest of the keyboard, and take that board, and find some bag of some sort (I used a static bag) and stick it in that, so it doesn't rub against anything on the inside of your computer, pop out one of the slot covers, for the wire, and toss it in there somewhere. run the keyboard wire out the back of the computer through the open slot, and plug it in. Now, the computer should think you have a keyboard connected, when you really don't. (I've you've got one of those gateway 2000 keyboards that came with the machines, this works really well. The board inside is about 2" x 3"; Good and small) Note: You may want to tape it on the inside somewhere, just so it doesn't move around too much.
Ok, this is where it gets fun. If you've got any stuff on this hard drive you want to keep, get it off of there somehow, because you're going to lose anything and everything on your drive. Before you do this, make sure you have some DOS Install disks laying around, and a boot disk, and DOS drivers for your CD-ROM drive (if you're going that route), and anything else you need. Go to DOS, and type:
Remember: YOU WILL LOSE EVERYTHING
Ok, now stick your DOS Install Disk in, and reboot. Install DOS, and if you're going to be using a network, install Windows 3.11 for Workgroups. (This boots fast, and does what you need it to do) I'm not going to go into details of all this, but if you need help with it, let me know.
Get your sound card driver, and CD-Rom Driver (if necessary) working before you continue
For the MP3 Player, I use DAMP. (http://www.damp-mp3.co.uk) I STRONGLY suggest you use this, because it does EXACTLY what you need it to do.
Create a folder on your hard drive called "Damp" and download the program, and put all of it's files there. Also, create a directory called "MP3" (also in the root), if you're going to put your files on the hard drive.
Copy an mp3 file to the computer, and experiment with Damp for awhile until you get it playing. It will take awhile to get it right, but it works great when you get done. All of the options are in the damp.ini file. Make sure the gui, and visualizations are disabled. (You're not going to have a monitor, so there's no point in slowing the processor to cause your mp3's to skip) Setup your Joystick to however you want it. I'm using a gamepad, rather than an actual joystick. (it's kind of a pain controlling with a joystick) Right now, I'm working on my own switch board for controlling, which plugs into the joystick port. Whatever you use, set the settings accordingly. Next, go to the sound section of the ini file, and set all of the settings. This part may be difficult to configure if you don't know all the settings. (Usually, the ini file for the driver of your sound card might be able to give you some clue [if there is an ini file]. Also, check your autoexec.bat, and config.sys files for some settings.)
Now that you've got it playing, you need to automate it. Go to dos, and type:
If there's a win command in there, get rid of it. If there's anything extra that you don't need in there, delete it. (You want this to boot up as fast as possible) Stick a command in there similar to:
(Note: damp allows you to use wildcards)
Now, when you boot up your computer, it will automatically start playing music. Tweak all of your settings and stuff now before moving on to the next step. Experiment with what works best. Also, fill up the entire hard drive with music, and make sure it's music you're gonna want.
Ok, so you throw the computer in the car, and realize, there's no 120v outlet. Hop in the car, go to town, and buy an AC/DC Inverter. Get one rated at a higher wattage than your computer. (example, if your computer is rated at 100 watts, get at least 150 watt inverter) Plug it into your cigarette lighter, or however yours hooks up, and plug your computer into it. Now, you've got power. Note: Make sure your inverter has a feature to automatically shut off when the battery gets low. Also, keep your car running while running the mp3 player, it draws a lot of power. (Note. . . Be sure to check how many amps you can get out of your cigarette lighter plug, and DON'T OVERLOAD IT. Use the equation P = V*I, where P = power in watts, V = voltage [12 or so], and I = current in amps.) Also, when figuring in how much juice you're gonna need, remember that your ac/dc inverter will probably only be 85% - 90% efficient, so factor that in.
Decide where you're going to put it. The best place, would be the trunk. The trick is finding a way to get some wires in there. What I did was I ran my wires through one of the rear speaker grills, and along side of the speaker, and down into the trunk. Other people have just drilled holes, but I don't suggest this with a decent car for obvious reasons.
One thing to be sure to do is figure out a way to hold the computer in place. When ya go around corners and stuff, the computer moves, and stuff gets unplugged, and it really ruins a song when it stops playing, or gets all noisy when wires move around and start to break. I've got some bricks around mine, but if you've got places to hook bungee cords on, use those. Just make sure it's nice and tight, and not going anywhere.
Musatcha is pronounced moo-SA-cha. I have no
idea where it originated.