What you need is either - Cubase, Protools, or Adobe Audition. There's pros and cons for them all, but I won't sit and go through them. I personally use Adobe Audition, because it's complex enough, but not too complex and has a lot of effects for digital mixing, and has multi track recording. However, if you do use this, then you'll also need a mastering program. Adobe Audition isn't very good for mastering at all.

Hardware wise - you'll need a mic and a mixer, interface, or preamp.

When choosing a mic, you're generally going to have the choice between a condenser mic and a dynamic mic. Dynamic mics are generally used for live performances, but can be used for recording, too. The Shure SM58 is a dynamic mic, but is widely used for recording and is a good quality mic. Bono from U2 uses the SM58. Dynamic mics give you a dryer, less warm sound. Condenser mics are more widely used for recording. They give you a warm, colourful, vibrant sound. It really depends on your voice, but I'd personlly recommend the Rode NTK. It isn't very expensive at all, and gives you great sound quality even with minimal mixing. I've never used it personally, but I have heard it being used, and know people who use it. Someone I know barely mixes their audio (just adds a little bit of reverb, does some dynamics processing, and does a little bit of EQing) and they have incredibly sound quality. It seems they get better sound quality than someone who uses the Rode K2, which is a step up from the NTK. I use the MXL V69 Mogami Edition, but the his are too sharp and it takes quite a bit of mixing/EQing to sort it out.

You'll also need a mixer, preamp, or interface. You can mix digitally, and the preamps in mixers are never as good as stand alone preamps, so it'd be almost pointless to get a mixer if you were recording and mixing digitally. Preamps require either a great computer sound card, or a decent external sound card. So you'd need to buy a preamp and soundcard if you went for that option. I recommend a USB/firewire interface. It basically works as a preamp and external sound card. Depending on how much you were willing to spend, you should look at something like the Fireface 400/800. Although, it's pretty expensive. If you aren't willing to spend too much, then a basic interface will suffice. Something like the Alesis I02 would work fine, you just won't get the optimal sound quality out of your mic. You'll get more-than-decent sound quality with the Rode NTK and the Alesis I02, but if you bought the Rode NTK and the Fireface 400/800, and your mixes were decent, you'd have pretty much studio quality. Although I wouldn't recommend the Alesis I02 if you needed more than two mic inputs and one guitar input.

I hope this helped.
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anther way to do it is get like a sound equalizer. Im not sure how it is set up but ive seen one hooked up to a pc. one with multiple channels would make it able to use multiple microphones. and do sound manipulations. I think you would use a convertor to change it from a say guitar looking jack to a pc micro cord . this would enable you to do more sound quality recordings.

The more better stuff you but would probably mean better groups would come there. I saw a picture of Dr. Dre's studio and he has microphones coming down from the ceiling and a HUGE mixing board.

I think there is a dude named del the funky homosapian that has a music video with him in his recording studio. its off his new album. you could check it out.

And finally if you are going to spend the big bucks you should definatly ask someone who has a nice one to take a tour of it before you spend big bucks

audacity = recording
virtual dj = turntables
download.com = free and trial music/sound programs
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