MQA

MQA, short for Master Quality Authenticated, is a digital audio encoding format developed by MQA Ltd. Introduced in 2014, it is marketed as a way to deliver studio master quality in a distribution file that requires less bandwidth than conventional high-resolution PCM.

The central idea is to fold or compress high-frequency information and other master characteristics into a compact bitstream, accompanied by metadata and authentication data. A device with an MQA decoder can unfold the file to reconstruct a version of the original master.

MQA is described as a three-stage process: mastering, encoding, and decoding. During encoding, the master is analyzed and an authenticated, folded representation is created. During playback, the decoder uses the embedded information and processing in the hardware to unfold the signal; some implementations offer a partial unfold, while others can perform a full unfold toward the master.

Usage and compatibility: Content encoded with MQA is distributed by selected streaming services and requires an MQA-capable decoder to realize higher-resolution playback. TIDAL has offered 'Masters' catalogs encoded with MQA; several hardware manufacturers provide MQA-enabled DACs and players. Not all devices or services support MQA, and some unauthenticated or non-MQA pipelines will play the file as standard resolution.

Reception and criticism: Proponents argue MQA can improve perceived quality by preserving essential master characteristics within a smaller file. Critics contend it is proprietary, may not be genuinely lossless, and relies on licensed ecosystems and hardware; debates continue about transparency and the consistency of 'unfolded' results across systems.