Making LR files is relatively simple once you do it a few times but many people get caught up on recording audio or struggle with low quality audio recordings. It's not difficult to make an audio file using the LR Easy Voice Recorder, but I am not a huge fan of recording my own voice if I don't have to. I tend to prefer a professionally recorded pronunciation if given a choice although it's slightly more work. Here's how to do it-
1) The easiest option for pre-recorded audio is to just download the MP3 version from an online dictionary website and add it to the LR file. Not all websites will let you download the pronunciation as an MP3 though.
2) If you cannot download the MP3 pronunciation, just record it. If you have two computers like many people do, instead of using a typical computer microphone with the easy voice recorder, just use a male-to-male audio cable. This is just like the kind you would use to plug your ipod into your car. Plug one end into the "Speaker" jack of your second computer and one end into your "microphone" jack of your main computer with LR on it.
3) Press "record" on the LR easy voice recorder and then press play on your second computer for the dictionary pronunciation of the word. You will see the pronunciation being recorded on the easy voice recorder but you will not hear it because the sounds are going directly into the microphone input of your primary computer. Then just highlight and delete any excess you don't want in the sound file and save it. Voila!
I first experimented by connecting the cable from the "speaker" jack to the "microphone " jack on the same computer and the quality was lousy. I don't think it works very well internally on the same machine, but on two computers it worked like a charm. I am not super tech savvy and even I could do this without issue. I think there are other ways to capture audio from your own machine using other audio programs out there, but I can't tell you anything about that. This was just a fairly simple way that worked for me.
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http://forum.brillkids.com/little-reader-how-tos-and-faqs/how-to-record-your-own-voice-and-picture-audio/msg1684/#msg1684) but