The Dequantizer can takes files of a certain bit depth (CD's are 16 bit, but you might also have recordings that use less), and calculate a few extra bits. It can clean up quantization noise in the process, if the recording was created without dithering.
This process does generate MP3-like artifacts, however the level of those is much lower than that of the noise that is removed.
Enabled Enables the Dequantizer.
Input Tells the Dequantizer how many bits the input signal has.
Setting this level too high creates more MP3-like artifacts, setting it too low won't fix all the quantization effects.
Reduction strength panel Maximum amount of quantization noise removal.
For dithered audio, this level should be set to 2, for non-dithered audio, 1 is sufficient.
Setting this level too high creates more MP3-like artifacts.
Maximum reduction Maximum amount of reduction per frequency.
Block sizes Determines whether only big blocks of audio are processed, or also smaller chunks.
Smaller chunks can lead to more accurate removal and a cleaner sound, but also more short-term MP3-like 'chirping' artifacts. It also uses more processing power.