MBIT+™ Dithering

This plug-in allows you to convert and dither to 24, 20, 16, 12, or 8 bits. This is useful for mastering a track for a CD (16-bit) from a 24-bit source, for example.

The MBIT+™ dither algorithm reduces quantization distortion with minimal perceived noise and produces smooth and quiet conversions.



Bit Quantization

Sets the bit depth to which you are dithering. MBIT+™ produces 32-bit floating-point output, but all low-order bits will be zero and should be truncated.

Type

Sets the type of dithering. MBIT+™ contains two traditional dithering types and a proprietary MBIT+™ dithering type.

  • Type 1 is a traditional dither based on a rectangular probability distribution function (PDF).

  • Type 2 is a traditional dither based on a triangular PDF.

  • MBIT+™ offers superior results when used with all types of source material.

Dither Amount

When using MBIT+™ dither, this controls the amount of dithering. The None and Low settings can leave some non-linear quantization distortion or dither noise modulation, while higher settings completely eliminate the non-linear distortion at the expense of a slightly increased noise floor. The Normal setting is suffice for most cases.

When using Type 1 or Type 2 dither, this controls the number of bits used to perform dithering. In most cases, 1 bit is suffice, but over-dithering with 2 bits can be useful in same cases.

Noise Shaping

When using MBIT+™ dither, this controls the amount of noise shaping. The choices range from no noise shaping to very aggressive noise shaping, providing approximately 14 dB of audible noise suppression, at the expense of a higher noise floor.

When using Type 1 or Type 2 dither, this controls the noise shaping. Dithering noise can be shaped in order to make it less audible. Simple noise shaping performs simple high-pass filtering on the noise. Clear noise shaping aggressively moves the noise toward the Nyquist frequency. Psych 5 is a 5th-order filter designed to move noise away from audible bands, and Psych 9 is a 9th-order filter with similar characteristics.

Auto-Blanking

If this option is activated, MBIT+™ mutes dither output when the input is completely silent for at least 0.7 seconds.

Minimize Peaks

If this option is activated, spurious peaks in the noise-shaped dither are suppressed.

Harmonics Suppression

If this option is activated, the truncation rules are slightly altered, moving the harmonic quantization distortion away from overtones of audible frequencies. This option does not create any random dithering noise floor. Instead it works more like truncation, but with better tonal quality in the resulting signal. This option is applicable only in the modes without dithering noise and without aggressive noise shaping.

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