How to Check the Real Bitrate of Audio Files
Understand the bit rate and its affection on the audio quality., Understand that the bitrate tag of audio files may not tell the true bitrate., After you understood these two facts above, know that the audio spectrum can tell you about the real...
Step-by-Step Guide
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Step 1: Understand the bit rate and its affection on the audio quality.
Though audio quality depends on many elements such as frequency, compressing method, up-scaled, etc., but for almost audio files downloaded on the Internet that have not been up scaled, if the bit rate is high (~128 kbps or higher), then the sound will be clearer and "more comfortable" to hear.
If the bit rate is low, you may hear it blurring, noisy and unclear. -
Step 2: Understand that the bitrate tag of audio files may not tell the true bitrate.
It is easy to convert a low quality 64 kbps MP3 file into a (so called) high quality 500 kbps M4A file.
This action is called "upscaling".
After upscaling, the audio quality is still not improved and it may be worse. , The spectrum (or chart) is a graph which shows the frequency (in kHz) and the loudness (in dB).
Many free programs such as Spek can help you build the audio chart/spectrum. , Observe the graph.
Notice the cut-offs.
The position of cut-offs can tell you the bitrate of the file.
Cut-off is the line put at where the graph cannot reach higher.
For example, an 128 kbps audio graph will be cut-off at 16 kHz.
Note:
The red line in the image below is not existed when you use an audio spectrum analyzer. , Cut-off at 11kHz.
MP3 file, Bitrate 128 kbps.
Cut-off at 16 kHz.
MP3 file, Bitrate 192 kbps.
Cut-off at 19 kHz.
MP3 file, Bitrate 320 kbps.
Cut-off at 20 kHz.
M4A file, Bitrate 500 kbps.
Cut-off at 22 kHz.
FLAC file, Lossless quality (Bitrate usually 1000 kbps or higher).
Graph's drawn continuously, no cut-off. , Its bitrate tag reads 320 kbps but the actual quality is 192 kbps. -
Step 3: After you understood these two facts above
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Step 4: know that the audio spectrum can tell you about the real quality and bitrate of an audio file.
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Step 5: Import an audio file in a spectrum analyzing program.
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Step 6: These following are spectrums of some popular bitrate and its cut-offs: MP3 file
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Step 7: Bitrate 64 kbps.
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Step 8: This is an example of an upscaled audio file.
Detailed Guide
Though audio quality depends on many elements such as frequency, compressing method, up-scaled, etc., but for almost audio files downloaded on the Internet that have not been up scaled, if the bit rate is high (~128 kbps or higher), then the sound will be clearer and "more comfortable" to hear.
If the bit rate is low, you may hear it blurring, noisy and unclear.
It is easy to convert a low quality 64 kbps MP3 file into a (so called) high quality 500 kbps M4A file.
This action is called "upscaling".
After upscaling, the audio quality is still not improved and it may be worse. , The spectrum (or chart) is a graph which shows the frequency (in kHz) and the loudness (in dB).
Many free programs such as Spek can help you build the audio chart/spectrum. , Observe the graph.
Notice the cut-offs.
The position of cut-offs can tell you the bitrate of the file.
Cut-off is the line put at where the graph cannot reach higher.
For example, an 128 kbps audio graph will be cut-off at 16 kHz.
Note:
The red line in the image below is not existed when you use an audio spectrum analyzer. , Cut-off at 11kHz.
MP3 file, Bitrate 128 kbps.
Cut-off at 16 kHz.
MP3 file, Bitrate 192 kbps.
Cut-off at 19 kHz.
MP3 file, Bitrate 320 kbps.
Cut-off at 20 kHz.
M4A file, Bitrate 500 kbps.
Cut-off at 22 kHz.
FLAC file, Lossless quality (Bitrate usually 1000 kbps or higher).
Graph's drawn continuously, no cut-off. , Its bitrate tag reads 320 kbps but the actual quality is 192 kbps.
About the Author
Samantha Foster
Committed to making cooking accessible and understandable for everyone.
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