I'm beginning to get asked a lot of questions about recording audio. I'm thinking about voice recordings of Scripture. Here are some things to think about:
- Equipment - you only need a
USB microphone or decent headset with microphone, or a condenser
microphone with pop filter and sound card (that plugs into your USB port)
- You also need to make an
acoustic baffle to absorb sound. This will cut out unwanted echo called
'reverb'. Reverb can always be added later but there is no button to
remove reverb, and people like FCBH, who we work with, are fussy about
these things, as they know a voice with reverb is hard to listen to and
understand (music, on the other hand, needs some reverb, especially the
vocals). https://www.youtube.com/watch?v=1bTK6tZzzaE
is a good video on how to make a simple acoustic baffle. You can make a
small tent in your room, but this gets hot and stuffy in places like
Central Asia...
- Make sure the sound level
is good. Too high and it will 'clip' (distort). Too low and it will sound
noisy. The best way to do this is to use a program like audacity and watch
the meter. It shouldn't go into the red, but it should be just short of
that. A good microphone will have adjustment built in, but you can always
adjust it in audacity, or in your sound settings in Windows. Don't use
automatic adjustment of the volume level as this will pick up a loud noise
then make the mic really quiet. Adjust it yourself. See below for some
screenshots:
- Think about file
management. If you record in Audacity or a similar program you'll have to
do all of this yourself. If you use an FCBH program, or SIL's 'Here This' you can let the
program take care of the file management for you. Remember that the files
should sort automatically in Windows, so you need to have 01Gen01, 01Gen02, 02Exo01 and
so on as your filenames, or use the local language filenames like
01GelipÇykyş01 only it's best to avoid special characters if you can. So
01GelipCykys01 or 01GelipChykysh01 will work better. In the end you want
your audience to be able to access these files (if on an mp3 player), so
use sensible names. Also you can make sure the metadata is correct. edit
that in a program like Groove. Here's
info on how to do that. Here's
info on how to change the filename of multiple files in one go.
Here's a screenshot of an audacity file with a good audio
level:
The meter is in the middle of the top, where it says 'Click to Start Monitoring'. You want the level to go up above -6db but not go over 0db. Sound levels are measured in decibels (db), and anything above 0 means it's clipping (distorting).
Or, with advice from an arts colleague, 'Rather than taking the risk of distortion clipping by trying not to get it to “go into the red”, record at a gain level that the voice max is around the middle of the meter (around -12). Then highlight the track -> effect -> normalize … -> OK (preset at -1). This will bring your clear audio signal to a strong signal with max of -1 (no clip). Then you will have a great strong signal and NO clipping.' This is a safer approach, avoiding clipping but keeping the signal strong.I hope that helps you to get started in sound recording! If you want expert help we have a whole department in SIL called IMS (International Media Services) who can give you better advice than me, and of course partners like FCBH too...
FCBH: Faith Comes By Hearing
Did you mean: it's clipping with everything higher than 1,0?
ReplyDeleteProbably 'higher than minus one'. Thanks!
ReplyDelete