DDi Codec — for Dolby B/C NR 4+

Digital Equivalent Dolby-B/C

Chen Wang

    • 5.0 • 3 Ratings
    • $15.99



Decoding/encoding Dolby B/C formatted audio in digital domain

DDi Codec is a precise digital equivalent of the classical Dolby-B/C noise reduction system for analog audio tape. 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/encoding can be performed in realtime pace, which allows instant monitoring and control of quality.

Deeper optimal result can be achieved by using the fine-tuning tools that come with the software, as specified below:

• The Reference Vernier is the primary tool for aligning Dolby Reference Level in an progressive and interactive manner. It supports either objective calibration (with Dolby Tone) or subjective estimation (without Dolby Tone).

• The Azimuth and Gap-Loss tools can compensate minor imperfection of an analog tape player used for digitizing audio tapes.

• The Play Trim is another tool for compensating weakened signal on aged pre-recorded tapes.

• The EQ Converter offers digital translation between IEC 120μs and 70μs tape EQ schemes — useful if such an options is not available on a given tape player/recorder.

• The built-in tone generator offers 400Hz 0dB signal at Dolby Reference Level for easy calibration.

All these tools can work independently from 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 allows the computer to perform as a outboard Dolby-B/C NR unit in one of the following four modes:
• Audio-In to File (a digitizer/recorder).
• File to Audio-Out (a player).
• File to File (an off-line processor, with batch capability).
• Audio-In to Audio-Out (a through processor, with slight delay).

Currently supported audio formats are:
WAV, FLAC, AIFF: up to 96k/24bit.
MP3, AAC, M4A: up to 48k/VBRS.
* Excluding some proprietary variants having the common file extensions, or additional format-normalization may be required.

A VST plugin is also available after the app has been installed.

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

What’s New

Version 2.7.1

- Added an option to save/load settings to/from a file.
- Added hotkey for showing up Audio Device dialog.
- Fixed a typo in v2.7.0

Ratings and Reviews

5.0 out of 5
3 Ratings

3 Ratings

Stereo_Steve-O ,

Amazingly flexible and effective tool for applying Dolby Noise Reduction to digital audio!

I am so thankful the DDi Codec exists. As an audio electronics engineer, I understand how complex Dolby can be, and I can tell that the developer of this app put in a lot of work to make it great. It sounds very accurate.

It's also a great learning tool for understanding Dolby NR. The in-app instructions for all the parameters and adjustments are explained very intuitively.

Also, the 120uS to 70uS converter that's included is very useful for anyone who wants to record with 120uS EQ onto Type II cassettes. I'm a big fan of this app, and I hope it stays functional and up-to-date for a long time. I also purchased the DxII codec for DBX encoding purposes.

100% unique nickname ,

Powerful yet simple, documented with care!

I'm picky about sound, but know nothing about cassette formats and have no gear to play a Dolby B tape correctly. DDi Codec is surpisingly approachable and flexible, it helped me get things closer to correct with the simple hardware I have.

Every single option is documented with practical explainations of how to use it! It's beautiful and so helpful! The docuntation doesn't just describe a button, it describes HOW and WHY it works the way it does, and tells you how to do things the best way (reference tones, etc.) or how to work with what you have.

App Privacy

The developer, Chen Wang, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    Up to six family members can use this app with Family Sharing enabled.

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