Recording a Radio Show on a Mobile Phone

myphone T23 Duo has a good sound recorder.

Finally, i have tried in full myphone T23 Duo’s sound recorder during my coverage with the business plan making seminar of the “Search for W.I.N.N.E.R.s” yesterday at the USC-SVD Study Mission Center.

All the voice recordings were used in yesterday’s episode of my radio show–“USC-Kapamilya Negosyo Na” over DyAB1512.

The result was amazing considering most cellphones have omni-directional microphone. Omni-directional microphones pick up sounds from all directions as its pick-up pattern.

Omni-Directional microphone picks up sounds from all directions.

Cardioid pick-up pattern is a heart-shape. The microphone picks up sound more at the front than its sides.

Image courtesy of Wikipedia: A cardioid generated by a rolling circle

The manual of the T23Duo doesn’t speak about its pick-up pattern characteristic whether it is omni-directional or cardioid which is widely-used in broadcasting. My suspicion, based on the way it picks up sounds during my recording, T23Duo has a cardioid microphone.

I have to convert first the AMR files into another format suitable for editing in my audio editing software.

Since the recording audio format was in compress and lossy format AMR, the recorded voices are a little dull. The Adaptive Multi-Rate (AMR) is common in GSM and UMTS mobile phones because of its speech format. But its sampling frequency is 8khz at 13-bit which is equivalent to the sound of a land line telephone–considered the lowest audio sampling quality.

Hence, i made a little audio enhancement on the recording using Adobe Audition to improve the quality. The tone is adjusted by lowering the low-band frequencies while increasing the mid-range and high frequencies using the graphic equalizer on my audio editing software.

The final result was amazing. It’s of broadcast quality. As if, i am using a professional voice recorder for my entire coverage of the event.