bx_stereomaker

Brainworx's bx_stereomaker addresses a persistent mixing challenge: how to expand mono sources without sacrificing phase coherence or introducing compatibility issues. The plugin employs M/S decomposition to synthetically generate a side channel from a mono input, effectively widening the stereo image while maintaining complete mono compatibility. This is technically sound - the process produces no phase anomalies when summed to mono, making it reliable for broadcast, streaming, and formats where mono playback remains relevant.

The algorithm uses frequency-optimized analog-style filters to create the virtual S signal, with particular attention paid to the midrange and high frequencies where width can easily sound artificial or thin. The Hi-Damp control proves essential here, allowing users to roll back high frequency expansion and preserve a natural, cohesive tone rather than achieving the brittle stereo effect common to less sophisticated upmixing tools. Full control over stereo width (0 to 300 percent) and the ability to solo the generated side channel provide genuine mixing flexibility.

The plugin excels on sources requiring careful balance between intimacy and space - lead vocals, centered acoustic guitars, and synth lines benefit most from its controlled expansion. Rather than applying broad reverb or delay effects that compromise focus, bx_stereomaker lets you widen the source itself while retaining definition and control.

Among comparable tools, this ranks as one of the few that genuinely respects mono compatibility as a technical requirement rather than an afterthought. It's most valuable to engineers mixing for multiple delivery formats or those working with legacy mono material needing careful integration into modern stereo mixes.