This compression discards audio that may be masked by other, more important, audio information. Lossy compression, as used in mp3 and AAC encoding, is the most common and uses data compression to reduce the amount of bandwidth that is needed to serve the audio. There are two broad categories of digital audio files: lossy and lossless files. Most companies only mention this in their fine print, but streaming quality depends on many factors, including network speed and the specific streaming/playback device. Also, each streaming service may lower the quality of audio that is delivered to a specific device.

When comparing streaming services (or any digital audio files), it is important to have some basic understanding of the audio qualities and anomalies to expect from each file type. Amazon and Tidal currently promote 24-bit, high-sample-rate audio, but much of the buzz around this high-resolution movement may just come down to marketing hype. Further, as explained below, high-bitrate and wide-frequency-response audio may provide subtle audio benefits, or it may be a hollow promise. This quality improvement requires more streaming bandwidth, so any user who would like to try out HD audio will need to first verify that their network and phone (or computer) is capable of receiving and playing these high-bitrate audio streams. We are all familiar with the low or variable quality of most audio streaming services, so HD audio promises to provide near-perfect audio.

The question for many customers may be whether or not they can actually hear the difference between Amazon’s standard streaming quality and the more costly HD streaming options. Amazon hopes to increase its market share by offering listeners millions of songs at CD quality, or better.

Amazon has recently debuted its upgraded Amazon Music HD and Ultra HD Streaming services.

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