Warren Sokol: Revolutionising Mastering with Sonnox Fraunhofer Pro-Codec

Warren Sokol, a seasoned production and mastering engineer at Universal Mastering Studios in Los Angeles, has adapted to the ever-evolving landscape of audio technology throughout his 20-year career. With experience on projects from Paul McCartney's "Live at Capitol Studios" to the Moody Blues' "Days Of Future Passed" and Lana Del Rey, Warren has embraced innovative tools like the Sonnox Fraunhofer Pro-Codec to enhance workflow efficiency and audio quality. In a recent interview, he detailed how the Pro-Codec has transformed their mastering process.

Universal Mastering Studios Setup

Universal Mastering operates three mastering studios and four production rooms dedicated to label work, editing, and quality control. The mastering rooms feature Lipinsky, Dynaudio, and PMC speakers, ensuring high-quality sound across various listening environments. For their primary DAW, they use SoundBlade with a dual-computer setup—one for the source and another for mastering.

Integrating Sonnox Fraunhofer Pro-Codec

Warren’s team has integrated the  Sonnox Fraunhofer Pro-Codec into their mastering workflow, particularly for a large-scale project involving specific mastering for AAC and MP3 files. Traditionally, mastering for these formats would take 9 to 10 hours per album due to the need for iterative processing and encoding checks. “With the Pro-Codec, it turns a 10-hour job into 3 or 4 hours,” Warren says, emphasizing that the plug-in has made sessions far more economical and practical.

With the Pro-Codec, it turns a 10-hour job into 3 or 4 hours Warren on his mastering workflow

The Pro-Codec has not only improved efficiency but also created new business opportunities. “We weren’t going to be able to do the job until I brought up that Sonnox had introduced a real-time plug-in designed for this type of project,” Warren notes. The plug-in's ability to monitor and meter in real-time allows Warren and his team to identify and address issues on the fly, ensuring optimal output quality for various codecs.

Adaptive Mastering Workflow

Warren describes their approach as adaptive mastering—tailoring the output to match the characteristics of AAC and other codecs. Depending on the project, the team might work with source mixes that need to match recent CD releases or adapt 24-bit/96 kHz masters originally prepared for CD.

“We start with our source and run the audio through the necessary processing. It then goes through a real-time sample-rate converter down to 44.1 kHz,” Warren explains. Using WaveLab, the audio is then processed through the Sonnox plug-in for monitoring and metering. This approach allows them to adapt and optimize the master for the intended codec, effectively pre-processing before the final encoding.

Real-Time Metering Benefits

The Pro-Codec's metering capabilities are crucial for identifying program-dependent changes in sound quality. “Changes in sound are very program dependent,” Warren says, highlighting how different genres, mixing styles, and levels of limiting can affect the encoding outcome.

He provides an example of a heavily limited track that, once processed through the sample-rate conversion and Pro-Codec, was clipping by 2 dB—even though it wasn’t clipping initially. The Pro-Codec’s real-time clip meters allowed Warren to adjust the gain, ensuring the final encoded file was free of distortion and artifacts. “It helps a lot to be able to see that in real-time with the Pro-Codec clip meters and just turn it down,” he adds.

Expanding Pro-Codec Use

Universal Mastering Studios currently runs three Pro-Codecs and plans to add more to keep pace with the growing demand for adaptive mastering. Warren points out that the Pro-Codec has become an essential part of their service offerings, even extending to independent and label artists. “Most third-party clients are going to be selling their music on the Internet or sending out the MP3s or AACs from their own websites,” he explains. The Pro-Codec allows them to evaluate multiple codec options to determine which sounds best for each specific project.

New Revenue Streams with Sonnox

Warren has been a long-time user of Sonnox plug-ins, but the Pro-Codec has been particularly transformative. “This one has literally created a new revenue stream for us. It truly makes our lives a lot easier,” he concludes. With the Pro-Codec, Universal Mastering Studios has not only enhanced its workflow efficiency but also expanded its service offerings, meeting the modern demands of digital music distribution.