The SPL Stereo Vitalizer MK2 is one of the most highly regarded psychoacoustic audio processors and “program equalizers” in audio production, mixing, and mastering.

Unlike a traditional equalizer, the Vitalizer applies principles of psychoacoustics and audiometry to enhance clarity, stereo width, and perceived volume by masking or emphasizing frequencies without introducing artifacts or negatively altering the signal.

Key Features

Psychoacoustic Reconfiguration (“Unmasking”): Utilizes small time delays to bring out audio details that are hidden or overlapped (“masked”) by louder frequencies, making the sound more transparent, defined, and natural.

Dynamic Bass Management:

Bass Selector (Soft / Tight): Allows you to shape the low-frequency response, making it soft and warm (Soft) or crisp and impactful (Tight).

Dedicated Low-Frequency Compressor: An integrated compressor that acts solely on the bass range generated by the Vitalizer circuit, increasing the presence of the bass signal without causing unwanted peaks.

Mid-Hi Tune & Process Section: Controls the cutoff frequency (from 1.1 kHz to 22 kHz) at which high-frequency enhancement and attenuation of intrusive mid-frequencies are applied, improving the clarity of vocals and instruments.

LC EQ Filter (High Frequencies and Harmonics): A coil (LC) filter dedicated to managing the very high frequencies and harmonics, designed to add sparkle and presence without sounding harsh or tiring to the ear.

Stereo Expander: An integrated circuit for widening the stereo image. It enhances the perception of three-dimensional spatiality while maintaining solid and consistent mono compatibility.