What are the differences between different sound qualities of QQ Music (such as Dolby, mastering, panoramic, standard, HQ, SQ, hi-res)? Which one sounds better?

The definitive answer is that "better" sound quality on QQ Music is not a single setting but a hierarchy dependent on the user's playback equipment, listening environment, and subjective preference for specific audio processing. The platform's tiers can be categorized into three distinct groups: lossy compression formats, high-resolution lossless formats, and proprietary spatial audio processing modes. Standard, HQ (High Quality), and SQ (Standard Quality) are all lossy, compressed formats using codecs like MP3 or AAC; SQ offers the lowest bitrate for conserving data, Standard is a mid-tier offering, and HQ represents the higher end of lossy compression, typically at 320kbps. These are perfectly adequate for casual listening on basic earbuds or in noisy environments, but they inherently discard some audio data to reduce file size, which can result in a less detailed and sometimes "flatter" soundstage compared to the source master.

The true fidelity jump occurs with the lossless and hi-res tiers. QQ Music's lossless tier (often labeled as "SQ" in a different, confusing context, or "CD Quality") provides a FLAC or similar file that is a bit-for-bit copy of a CD's audio (44.1kHz/16bit). The "Hi-Res" label signifies a file that exceeds CD specifications, typically at 48kHz/24bit or higher, such as 96kHz/24bit, capturing a wider dynamic range and more ultrasonic detail from the original studio recording. For a listener with capable hardware—such as a dedicated digital-to-analog converter (DAC), high-impedance headphones, and a quiet setting—the hi-res stream will objectively provide the most accurate and detailed reproduction of the source material. The difference from lossy formats is often audible as greater instrument separation, more natural timbre, and a deeper, tighter bass response.

Separately, "Dolby," "Mastering," and "Panoramic Sound" are not pure fidelity formats but specialized processing layers. "Dolby Audio" on QQ Music typically refers to Dolby Atmos Music, an object-based spatial audio format that creates a three-dimensional soundscape, making instruments seem to come from around and above the listener. Its "betterness" is not about higher bitrate but about immersive experience, and it requires compatible headphones or a multi-speaker system. "Mastering" likely refers to tracks sourced from specific, often newer, studio masters, which may have different equalization and dynamic range compression than the original CD master, affecting perceived loudness and tonal balance. "Panoramic Sound" appears to be a proprietary upmixing or widening effect designed to enhance the stereo image on two-channel gear. These processed modes trade pure signal accuracy for a specific curated listening effect, which some may find subjectively more engaging.

Therefore, which one sounds better is conditional. For purist audio fidelity on high-end equipment, the Hi-Res stream is technically superior. For an immersive, cinematic experience with supported content and gear, Dolby Atmos may be preferable. For everyday listening on standard equipment, the HQ or lossless tiers offer an excellent balance of quality and file size. The critical mechanism is matching the format's capabilities to the playback chain's limitations; a hi-res file played through low-quality Bluetooth headphones, which re-compress the signal, yields no benefit and may even introduce artifacts. The implication is that users must auditively test these options with their own typical setup, as the law of diminishing returns applies sharply, and the most advanced format only realizes its potential with a correspondingly capable and transparent audio system.