Understanding Digital Audio Quality
The quality of audio can be a difficult thing to understand as well as hear, but as music playback devises continue to improve, the quality of audio will become more and more apparent. Of coarse, the composition, arrangement and performance are the top priorities in any professional recording. However, the resolution of the audio being recorded as well as the quality of the final product must be taken into consideration in order to achieve professional results. Below are some concepts to consider.
Sample Rate: This is the frequency at which an analog audio signal is sampled at and converted to digital. Standard CD quality is sampled at a rate of 44.1Khz (44,100 samples per second). DVD and Blue-ray are sampled at 96Khz.
Bit Depth: This refers to the number of bits in each digital sample of audio. Standard CD resolution is 16 bit. DVD and Blue-ray are 24 bit. Most professional recordings are done at 24 or 32 bit.
Bit Rate: This is the rate at which digital audio is streamed at. Mp3 bit rates range from 32Kbps (32,000 bits per second) to 320Kbps. Amazon and iTunes now use 256Kbps.
Comparing CD to Mp3: In order to compare CD quality to Mp3 we must multiply the CD sample rate of 44,100 by the bit depth of 16 to get 705,600 or 705.6Kbps. This is then multiplied by 2 for a stereo audio file to get 1,411.2Kbps. This is the bit rate of a standard CD which is over 4 times greater than the highest quality Mp3 of 320Kbps.
Comparing DVD to Mp3: To get the bit rate of DVD we multiply its sample rate of 96,000 by its bit depth of 24 to get 2,304,000 or 2,304Kbps. This is then multiplied by 2 for a stereo audio file to get 4,608Kbps. This makes DVD and Blue-ray audio resolution over 14 times higher than the best quality Mp3 of 320Kbps.
The better the playback devise, the clearer these differences in audio quality become. You might not hear much of a difference between Mp3 and CD resolution when listening to the built in speakers on your phone but when listening on a high fidelity sound system, there is a significant difference that anyone can hear. Please contact us here at TapwaterProductions.com with any questions you may have about audio quality or to get your next music project started.