Do you have a digital audio recorder? Are you looking to capture electronic voice phenomena? Before you do you, let’s sit down and discuss how a digital audio recorder works and some basics about the MP3 format and generic recorder settings:
How many kilobits the file uses per second. With low bit rates, there are compression artifacts such as ringing or pre-echo are usually heard. This is particularly noticeable when a recording has lots of random changes. 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 (Supurovic) being the most common. I often describe lower bit-rates as being more “tinny”. For a good example, listen to white, pink and brown noise uncompressed and then compressed to 8-bit sound here: http://noisey.vice.com/…/yntht-there-are-ghosts-in-your-mp3s
Due to the Nyquist/Shannon Theorem, a rate of 2x your hearing range is ideal. (44khz for most humans). This bitrate is the most common as it is tied to CD Audio conversions. Think of sampling frequency as having more “slices” of sound allowing it have a more rounded sound. For those math people, digital audio is a square wave but we hear in analog, the more squares waves you have (shorter slices) the closer you can approximate the analog wave.
Why use MP3:
MP3 compresses sound information to store in a more space efficient method than raw audio information. This compression does come at the price of “quality” as some information is lost in order to fit into a smaller space. The question becomes what is “lost” in your recording. Many people view modern encoders as being similar (Amorim). I leave this to your own personal preference and storage space constraints. I personally prefer the FLAC and OGG formats; however, many digital records do not natively record in this format.
Amorim, R. (n.d.). Results of 128kbit/s Extension Listening Test. Retrieved April 28, 2015, from http://listening-tests.freetzi.com/…/128kbps_Extension_publ…
Sony IC Recorder Operating Instructions ICD-PX312. (n.d.). Sony.
Supurovic., P. (1999, December 22). MPEG Audio Compression Basics. Retrieved April 28, 2015, from http://www.mpgedit.org/mpgedit/mpeg_format/mpeghdr.htm
Wilkinson, D. (2015, March 18). Meet the Musical Clairvoyant Who Finds Ghosts In Your MP3s. Retrieved April 28, 2015, from http://noisey.vice.com/…/yntht-there-are-ghosts-in-your-mp3s