Without specialized speakers or headphones, as commonly used in dailylife, you cannot distinguish the quality between lossless audio and lossy audio. Especially in your mobile devices, storage space often comes at a premium, you know. To solve this problem, you may want to compress audio file to save more space.
How to compress audio files? A handy audio compressor software is more helpful. There are two ways to reduce audio file size: convert lossless audio to a lossy audio format and lower audio bitrate. In either way, the final quality depends on the source file quality. Actually, a bunch of freeware can be used as an audio file compressor or music compressor. Take the well-known Freemake for instance, import your source audio file > choose MP3 or AAC, WMA, etc lossy format as output format > start to convert. If the source audio file is already a lossy format, then lower the audio bitrate, but better not go lower than 128 kbps for keeping the acceptable quality.