Sound Performance Lab (SPL) is a German manufacturer celebrated for its high-end audio processing equipment that combines precision engineering with musicality. Best known for innovations like their 120V rail technology, SPL’s gear offers exceptional dynamic range, clarity, and headroom, making it a favorite in mastering suites, professional studios, and broadcast environments. Flagship products like the Phonitor headphone amplifier, Iron mastering compressor, and Vitalizer psychoacoustic enhancer showcase the brand’s commitment to both technical excellence and sonic character.