What is the most efficent way to convert a sample?

[tombikadam]

think about that you have vsti and wanted to convert to korg format, I know awave can do this but what about the settings, when I convert a sound to sf2 for example, the file size is 10MB, but when I convert it to KMP it is 5MB, %50 profit, but I don't know the details about converting, my aim is to convert a sound without quality loss and filesize is important too... any ideas?