DDi Codec is a precise digital equivalent of Dolby-B/C analog tape noise reduction system. It is the world's first dedicated software capable of decoding or encoding Dolby-C formatted audio in digital domain, along with full backward compatibility to Dolby-B. Powered by the proprietary DSP engine, the decoding or encoding can be performed in real-time pace, which allows instant monitor and control of quality.

The software also comes with an unique set of fine-tuning tools for reducing tracking errors in practice. Deeper optimal result can be achieved by effectively using the tools, as specified below:

• The "Reference Vernier" is a novel widget for determining Dolby Reference Level in an interactive and progressive manner. It supports either objective calibration (with Dolby Tone) or subjective estimation (without Dolby Tone).
• The azimuth and gap-loss compensation tools are the digital efforts of remedy in compensating minor imperfection of an analog tape player used for digitizing audio tapes.
• The "Play Trim" is another digital tool for compensating weakened signal often found with a degraded pre-recorded tape.
• The EQ Converter offers digital translation between 120μs and 70μs IEC tape equalization formulas — if such a flexibility is not offered by a given tape player/recorder.
• The built-in tone generator offers 400Hz 0dB signal at Dolby Reference Level for easy calibration.

These fine-tuning tools can work independently of the Dolby-B/C codec, which can also be applied for refining non-Dolby formatted audio.

DDi Codec is a stand-alone GUI app without relying on any other DAW host. It let the computer perform as a outboard Dolby-B/C NR unit in one of the following 4 working modes:
• Audio-In to File (a digitizer/recorder).
• File to Audio-Out (a player).
• File to File (an off-line processor).
• Audio-In to Audio-Out (a through processor, with slight delay).

Currently supported audio formats are: WAV, MP3, FLAC, AIF, AAC and M4A, up to 96k/24bit.

* Dolby-B and C are the tape noise reduction systems developed by Dolby Laboratories.

What’s New

Version 1.7.1

Improved the mono output mode in order to give better assistance to the azimuth correction tool.


Chen Wang
8 MB

OS X 10.8 or later, 64-bit processor



Age Rating
Rated 4+
© 2019 Anaxwaves


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