Here is a good article for those of you who are wondering where we’re at in regards to wireless sound quality. You’ve probably heard of aptX, which is basically a codec that gets around the limitations of Bluetooth with compression. Based on this reader’s experience, aptX, when coupled with a pair of quality headphones, provides quality that is nearly indistinguishable compared to a wired set.



…how can aptX make a difference, considering it is still operating within the restriction of the 345 Kbps Bluetooth audio streaming specification? The difference is in the way the signal is compressed before being transmitted, as aptX does not use psychoacoustic techniques to achieve its compression. It is still considered “lossy”, but aptX uses time domain-based, not frequency domain-based, compression using ADPCM (adaptive differential pulse-code modulation). With the ADPCM compression used in aptX Bluetooth streams, the difference between the quantized samples can be transmitted and used to reconstruct the original signal on the receiving end, saving data, and therefore valuable bandwidth.

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Source: [H]ardOCP – Qualcomm aptX Bluetooth Review: Improving Wireless Sound