The utmost cares were put to achieve the best playback system to play the mixes since the quality of the mastering is bounded by the quality of the playback of the sources itself. All the gears in the racks including lots of the original Mastering Lab gears are custom built or heavily modified by the Mastering Lab and Josh Florian at JCF Audio using topologies, and parts that are tested through the careful listening evaluations

To ensure the quality playback system, the electric power is kept as clean as possible. Right from the electric pole, a new power line was established, even then, the power for the audio devices was totally separated from other sources that emanate noises such as computers, appliances, lights and so on.

Since we're not a big fan of DSP(Digital Signal Processing), our signal chain is retained on analog domain across the board. But for some spots that we can't avoid using DSPs such as a brickwall limiter, oversampling filters on DAC, ADC circuits, we have implemented a revolutionary, unconventional DSP system which sprang from the 2 years' research on this area to make sure the DSP leaves the smallest amount of artifacts possible.

As The Mastering Lab founder Doug Sax likes to say "If Sunny had not existed, I would have tried to invent him."

Prior to joining The Mastering Lab in July, 2005, Sunny had been a mastering engineer at his own facility in Seoul, Korea for five years. He is an experienced recording engineer, record producer and choir conductor. Coupled with his extensive studio and musical experience, he also has a Bachelors of Science in Computer Science, which gives him an exceptional capacity to marry the artistic with the technical. This "man of all seasoning" has mastered the unique Mastering Lab transfer system and won the hearts of all that have met and worked with him.

In 2012, Sunny founded the Jacob's Well Mastering in West Lebanon, NH.

Sunny’s impressive credentials and skills have endeared him to many top acts, including: David Gilmore, Keith Urban, Jeff Lorber, Steve Vai, Lee Ritenour, Izzy Stradlin, Boney James, Graham Nash, Linda Ronstadt, Barry Manilow, Patti Austin, Larry Carlton, Kurt Elling, Peter Sheindler, Saltacello, Orientango, National Poland Symphony Orchestra, Daejin Kim, Young Ok Shin, Jane Monheit, Russell Watson, Billy Ray Cyrus, Marc Antoine, Gerald Albright, Warren Hill, Matt Dusk, Selah, Bauhaus, Jazzotheque and Double Rainbow.