Heh. As dmcsilva suggests, this question has been asked a thousand times and it has a thousand different answers. Because we really don't know your setup it's hard to say what you need. But I'll make a little list that might point you in the right direction. There is no "magic" cable though.
1) You need a microphone and a microphone preamp UNLESS your acoustic has electronics in which case you can get away with a Direct Input box to amplify the signal from your guitar. Any preamp (or effects box) will work though, but DI boxes are designed for those who want to record direct (without a microphone).
If the electronics in your guitar are active then you might get away without a preamp but it won't sound great.
2) You need a somewhat decent computer with a quick processor and a fast hard drive with lots of free space. Expect to burn about 10MB per minute of recording at 44.1Khz 16bit (that's per track!)
3) You need a decent soundcard. There are cards designed especially for recording, but you can get away with using a cheapo card. I use a garbage SB16 that works well enough, but I've tried other cheap cards (ES cards specifically) that just don't work at all. The card needs to be "full duplex" which means that it can playback and record at the same time.
4) You need multitracking software or at a minimum a wave editor. I'd recommend starting out with n-Track because it's hundreds cheaper than the big time stuff...and you can download a shareware version from
http://www.fasoft.com
5) Assuming you're going to use the soundcard that came with the PC, you'll need an adapter to plug your preamp into the LINE IN port on your soundcard. No, you can't use the Microphone jack...don't even try. The Line In port on your soundcard will be a standard 1/8" stereo jack...so you'll need a male 1/8" to WHATEVER adapter or cable. Typically you'll use a 1/4" to 1/8" adapter, but it depends on what you're using. Because of my mixer I use RCA to 1/8". Just think logically, you have an output jack on your preamp and an input jack on your soundcard. Go down to radio shack and buy a cable that'll hook 'em up.
Watch your levels and start quiet...you don't want to blow anything up.
6) Forget MIDI for now. A while back when I was just beginning to learn about computer recording, I too thought that MIDI was the answer. You can use MIDI to add other instruments to your music...but when it comes to your guitar you want to record the guitar itself as you're playing. You might use MIDI down the road to add sampled instruments like drums and horns to your music.
7) You need good headphones with real speakers....not the toy phones that come with your walkman. I use a pair of Sony phones that weren't expensive and sound good. Avoid any headphones that advertise "Bass Boost" or any sort of EQing ("makes your music sound great!"). You want to hear the music how it really exists.
The headphones will be used to listen to the music that you've already recorded while you're recording a new track.
8) A decent set of monitors to get your mixes right. If you can't afford monitors (like me) then your best bet is to have a lot of different systems at your disposal to listen to your music on. I use my computer speakers, my Sony headphones, a pair of cheap headphones, a boombox, and my car stereo. A tape deck comes in handy with this technique.
Wow. Here's the idea in a nutshell. The signal coming out of your guitar or microphone is very weak. The Line-In port on your soundcard is not amplified. Therefore you need a way to boost the guitar/mic signal and run it into your soundcard. In comes the DI box or preamp. Your sound will be EXTREMELY dependent on the type of microphone, preamp, or DI box you use. The best way to get a natural sound is to use a good microphone/preamp to mic your guitar (or amp).
Scared yet?
Keep asking question. There are a few pros here and a lot of amatures like me...and we're all willing the help.
Slackmaster 2000
