Audio techies -- Shrinking sound files

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VinceC

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Any audio techs among us?

I'm looking for simple to use software that will compress audio files.

I'm working for a government press office and want to transcribe our news conferences for posting online. My first adventure down this road resulted in the digital recorder spitting out a 40-minute digital file that is a 25-megabyte .WAV file.

That's too large to email to our transcriber.

Our news conferences include a lot of non-native English speakers, so I want the higher fidelity in the master recording to be able to understand them clearly.

I've tried various online shareware programs to convert to mp3 and wma files, but the size remains stubbornly stuck at 25mb.

Content seems to be about 22,000hz, 88kb, 16 bit. That exhausts my technical knowledge of this subject.

Anyone know of a reasonably easy to use program that gives you control over compressing sound files without getting an advanced degree in digital audio theory?

It seems to me that every other teenager is accomplishing this already with music CDs. So I was surprised how complicated this seems to be when I started doing Internet searches and downloading programs. I thought I was pretty tech savvy with PhotoShop and being able to hook up DSL connections in foreign languages I don't speak. But trying to compress a basic audio file has me at my wit's end.

(Tech problems like these are why I like to come home to my rangefinders.)

Thanks in advance for any assistance.
 
Audacity ( http://audacity.sourceforge.net/download/windows ) will do what you want fairly easily. It's available for many platforms, not just Windows.

Encoding MP3 files with Audacity requires the LAME MP3 encoder, downloadable here: http://lame.buanzo.com.ar/

It's all free software, so there shouldn't be any licensing issues.

Unzip the LAME file and copy the lame_enc.dll file to your C: drive.

Open Audacity and go to File->Open, and select your .wav file. Go to File->Export As MP3... Choose the location to save the converted file. The first time you run the MP3 conversion, it will tell you it needs the LAME MP3 encoder. Say YES, and go to the C: drive where you copied it, and click Open. Audacity will now encode your audio file as an MP3. A 50mb .wav file will generally result in a 4-5mb MP3. The next time you convert a file, Audacity will not need to ask for the location of the encoder.

If the resulting MP3 is not good enough, you can increase the bitrate in Audacity. Go to Edit->Preferences, click on the File Formats tab, and change the bitrate under MP3 Export Setup (the bottom section) to 192 or higher. Default is 128, I believe, which is not bad, depending on the source material. The higher the bitrate, the larger the final MP3, and the higher the quality.

One Caveat - emailing any file larger than ~1mb is sketchy. It might or might not get stopped by a mail server along the way for being too large. A more elegant solution is to post the audio file to a web server, and email a link to the file. I admit this can get to be a hassle as well if you don't have access to a web server yourself, but eliminates the issues of emailing large files.
 
Many thanks. I'll give that a try when I get home (government computers won't let me easily experiment with new software).
 
40 oz

Thanks! That worked like a charm. I actually went for the lowest bitrate, 16. There was no meaningful loss in sound quality (human voices don't have the same range as violin concertos) and the file was about 4.5mb, a size I've dealt with before with production-quality photos and video.
 
I'm sincerely glad I could help 🙂

I did it myself while I was writing it, and I agree that it is harder than it should be. Apparently, most programs that can create MP3's from .wav files are useless if it's not on a CD 😕 As a programmer, I apologize for the narrow vision of my brethren 😀
 
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