You've probably heard of h2g2's AViators by now. We're a volunteer group putting together audio-visual content for h2g2, some being based on guide entries, some being closer to the content of The Post, and we're looking for contributions! We realise that recording audio with a computer isn't an everyday activity for most people, hence this practical, non-technical guide to the basics.

You will need:

• A soundcard - there will probably be a soundcard in your PC or built into the motherboard. If you have a pair of pink and green mini-jack sockets you've got a soundcard. If not, they can be picked up quite inexpensively. A convenient alternative to an internal soundcard is an external one that connects via a USB (Universal Serial Bus) port.

• A microphone - you can use a headset mic but a stand-alone mic will be much better. You can get relatively good mics that plug straight into a USB port but they tend to cost from £40.00 upwards, so are probably too expensive for many.

• Recording software - there is a sound recorder built into Windows but it's rubbish. Macs have better software but this guide will be based on Audacity, which is free and runs on Windows, Mac and Linux so can be used by pretty much anybody (unless you're still using an Amiga. Kudos to ya' but no matter how much we respect your loyalty we can't cover all possibilities.) If you buy a soundcard it will probably have recording software bundled with it. It probably won't be as good as Audacity;

• Headphones.

Plug in your microphone and headphones then fire up Audacity. Go to 'Preferences' at the bottom of the 'Edit' drop down menu. In the 'Audio In/Out' tab select your soundcard in both the 'Playback' and 'Recording' options. In the 'Quality' tab select 44100Hz. Click OK, select 'Microphone' from the drop down menu on the middle of Audacity's menu area, hit the 'Record' button (the one with the red circle) and speak into the microphone. You should see a wave being drawn in the main window as the audio is recorded. Excellent, you've recorded something! Stop Audacity (the square window, sorry, button) then hit play (the green triangle) and you should hear your voice through the headphones. Weird isn't it? You'll get used to it!

There is more to recording than just hitting a record button. Things you need to pay attention to are:

• Level - you need to get the loudest possible signal while ensuring that you don't make more noise than the computer can deal with. The meter at the top right of Audacity (with the microphone picture under it) shows the input level. Hit record, speak into the microphone and adjust the input volume (the slider to the right of the drop-down menu you selected 'Microphone' in earlier) until it peaks at around -12. Anything under 0 is theoretically OK but it's wise to leave a margin for error; a distorted digital signal is very, very unpleasant. Unless you're Aphex Twin, in which case it's a career, but if you're Aphex Twin you're unlikely to be reading this.

• Microphone placing and technique - another important factor in getting the level right. You should ensure the microphone is set up to be as stable as possible and so that neither it nor its cable will be knocked or brushed against. Proximity to the mic is very important; too close and you might end up sounding 'boomy' and could cause 'plosives' (the popping and booming sounds that you sometimes get on Ps and Bs, caused by a sudden, relatively high pressure lump of air hitting the mic), too far away and you'll sound, well, you'll sound too far away. Also, most of us have solid walls, windows and furnishings in our rooms which cause reflections from your voice which the microphone can pick up. Again this will make you sound distant. If you've a padded room by all means use it (after checking it's not occupied or the occupant is sedated) but if not you should try to minimise room reflections by being close to the microphone and, if possible, near soft furniture which will absorb some of the reflections. This really is a matter of trial and error.

Audacity has a lot of effects which can be used on your audio. By all means play about with them but if you're recording for the AViators please export your audio first (see the next section) so we have your naked voice. This makes it easier for us to adjust things and get the same feel for all the audio (or as close as we can get anyway.) It's a good idea to export it with a word in the file name that indicates the file hasn't been played with, such as 'dry'. For example, if recording a piece called '2legs Took My Sanity' you could export the bare audio file as '2legstookmysanity.dry'.

You'll need to decide which format you want to use for your finished file. There are many but .mp3 and .wav are the most common. mp3s are more widely used but of inherently lower quality than .wavs so, if possible, you should try to export as a .wav; you can always convert to mp3 later if you need to.

Secondly you need to decide the quality you're aiming for. Too low and you'll sound somewhere between an old telephone conversation and a Commodore 64 speech synthesizer. Too high and your computer will be struggling to keep up with the mental arithmetic. For .wav files 16bit/44.1kHz is sensible (and widely compatible, being the quality used for CDs); mp3s do things a little differently and 192kBps/44.1kHz, while of lower quality, is a good compromise. Don't worry, you don't need to know what those numbers mean, you just need to know how to tell Audacity to use them!

Go to the 'Preferences' box in Audacity (at the bottom of the 'Edit' drop down menu) and click the 'File formats' tab. Set 'Uncompressed Export Format' to 'WAV (Microsoft 16 bit PCM)' and in the 'MP3 Export Setup' section set the 'Bit Rate' to 192. Then click OK and the job is done.

If you export as .mp3 Audacity will need LAME (think of the audio you've recorded as the ingredients for the mp3 meal: LAME is the cooker.) You might already have LAME on your PC but, if not, download it, stick it somewhere memorable (possibly in a folder in My Documents) and go back to the 'File Formats' tab in Audacity's Preferences. Click 'Find Library', click OK on the next box, navigate to the place you left LAME, double click the LAME icon and you should find that Audacity will now export mp3s quite happily.

Piece of cake. Go to the file menu and select 'Export as Wav' or 'Export as MP3', select the directory you want it in, type in a filename, click OK and wait for it to do its thing.

You are now set up to record and export decent quality audio recordings. Get to it!

• Audacity

• LAME

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