Mastering in music is the final stage of audio production — the process that happens after mixing and before distribution. Its main goal is to make a song sound polished, balanced, and consistent across all playback systems (headphones, car stereos, club sound systems, streaming platforms, etc.).

Here’s a breakdown of what mastering involves:

1. Final Sound Balancing
   
   

• The mastering engineer listens critically to the stereo mix and makes subtle adjustments to EQ (equalization), compression, and stereo width.
• These tweaks help balance the low, mid, and high frequencies so that nothing sounds too harsh, muddy, or dull.

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2. Dynamic Control
   
   

• Using limiters and compressors, the engineer ensures the track has the right level of punch and loudness without distorting or losing clarity.
• The goal is to compete sonically with professional releases while maintaining musical dynamics.

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2. Stereo Enhancement and Depth
   
   

• Mastering can slightly widen the stereo image, enhance spatial clarity, and ensure the mix translates well to mono playback too (like on phones or small speakers).

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2. Loudness Optimization
   
   

• Tracks are prepared to meet the loudness standards of modern streaming platforms (like Spotify, Apple Music, or YouTube), so they sound even and consistent across services.

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2. Final Cleanup
   
   

• Any clicks, pops, hums, or noise that slipped through the mix can be removed.
• Fades, track spacing (for albums/EPs), and metadata (like ISRC codes) are also added here.

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2. Exporting for Distribution
   
   

• The mastered file is rendered into the final formats needed for digital or physical release (e.g. WAV, MP3, DDP for CD).