Most of the time when people stream audio all they care about is the bitrate. The thought is- more bitrate better audio quality but this is not the full truth. When you are streaming audio you need to watch a few things to get the best audio quality you can from your bitrate. For example, getting better audio is a combination of Bitrate (kbps), Frequency (Hz) and if the streaming is mono or stereo. I will try to explain this as simply as possible.
Bitrate is defined as the number of data points used to approximate the true wave form. Obviously, the higher the number, the more accurately the wave form is approximated. Radio streams are encoded (compressed) to a ‘bitrate’. The bitrate simply refers to the audio quality of the stream; this is measured in computer terms in ‘kbps – kilobits per second’ or ‘k’ for short.
Sampling frequency also impacts fidelity. The sampling frequency is essentially the number of times the sound event is quantized within a given time period. Sampling frequencies are specified in KiloHertz (KHz), a term meaning samples per second. The key in understanding how sampling frequency affects fidelity is the Nyquist sampling theorem. Basically, when applied to audio signals the Nyquist theorem states that the highest possible pitch in the sound is one-half that of the sampling frequency.
Mono Vs Stereo
Most users automatically assume that because it is set to stereo it will sound better. This is not the case- using stereo on a lower bitrate will cause muffled audio. For example – 48kbps on stereo would mean you are only getting 24kbps per channel. This decreases the end listener’s experience of your stream, with mono it will sound better for them. On 128kbps for example, you are getting 64kbps per channel. This means the overall quality will be improved offering a good stereo, crystal clear audio to the end user.
The following is a table with MP3 parameters combinations for your encoder.
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