The .vqf file extension is used for TwinVQ files. The TwinVQ is an audio format which was developed by Nippon Telegraph and Telephone Corporation and marketed by Yamaha by using the SoundVQ as name. It was announced by the developers that TwinVQ files are about 30 to 35% smaller than MP3 files of a certain quality. The higher quality is achieved at the cost of higher processor usage.
VQF file format
The file with .vqf extension is actually belongs to the TwinVQ audio format which was also known as an audio compression technique. This technique has been used in both proprietary and standardized designs. We can say that TwinVQ is an audio codec which is enhanced for audio coding at ultra low bitrates around 8 kbit/s. TwinVQ uses Twin vector quantization. This codec supports constant bit-rate encoding at 80, 96, 112, 128, 160 and 192 kbit/s. Yamaha marketed this compression audio codec as an alternative to MP3, but the format never became very famous, because of propriatery nature of TwinVQ format, the encoding was extremely slow and there was not much music available in TwinVQ format.