Undertone Audio MPEQ-1 Plugin — Free Download

Purpose and Heritage

The MPEQ-1 Super-Parametric Saturation Equalizer plugin brings a celebrated analog equalizer into the digital realm while expanding its capabilities. Its hardware predecessor was known for doing things most digital EQs could not, and this plugin aims to match that legacy. The developer waited until they could add something genuinely new to the digital world, rather than simply cloning the original.

The plugin retains everything that made the hardware iconic: variable filter shapes, exceptionally versatile filters, wide-range Q control, and the unique Vari-Phase mode. Every element that contributed to the original’s reputation has been meticulously recreated. This is not a simple emulation; it is a digital instrument designed to stand alongside its analog counterpart.

Key Capabilities

The most significant addition is that each EQ band now includes its own dedicated saturation stage. This allows for rich harmonic coloration on a band-by-band basis. You can boost high frequencies into saturation while carefully carving out low-mids and leaving the low end completely clean. The ability to treat each band differently opens up new creative possibilities.

For example, you could push a snare drum’s fundamental frequency until it sings while keeping the top end pristine. Similarly, you can add warmth to a vocal’s presence region without affecting the body. This level of control is described as unprecedented, giving engineers the power to shape tone and texture simultaneously within a single EQ.

Workflow and Applications

In practice, the MPEQ-1 plugin functions as a surgical yet musical tool. The variable filter shapes allow you to move between smooth, gentle curves and sharp, aggressive cuts with ease. The wide Q range means you can make precise adjustments to narrow problem frequencies or broad tonal shifts, depending on the material.

For mixing, the per-band saturation is perfect for adding harmonic excitement to individual elements without affecting the rest of the mix. On a master bus, it can add subtle glue or intense character, depending on how hard you drive the bands. The plugin is equally suited for tracking, allowing you to shape sounds as they are recorded.

Practical Use Cases

One compelling use is on drums. By boosting the snare’s fundamental with saturation, you can make it more present and powerful without needing additional processing. Meanwhile, the low end can be left untouched for a clean, punchy kick. This kind of selective processing is what sets the plugin apart from traditional EQs.

For vocals, you might saturate the upper mids to add presence and bite while keeping the low-mids clean to avoid muddiness. The Vari-Phase mode offers additional tonal options, letting you shift phase relationships for unique frequency responses. Once you experience this level of control, it is hard to return to conventional EQs.

Key features

• Each EQ band includes a dedicated saturation stage for harmonic coloration
• Variable filter shapes allow for flexible tonal sculpting
• Wide-range Q control for precise or broad adjustments
• Vari-Phase mode provides unique phase-based frequency shaping
• Meticulous recreation of the hardware MPEQ-1’s core behavior
• Combines equalization and saturation in one tool for efficient workflow

Best for

Ideal for producers and mixing engineers who want to add analog-style harmonic richness and precise tonal control simultaneously. Excellent for drums, vocals, and individual tracks where band-specific saturation is needed, as well as for master bus shaping where subtle or extreme coloration is desired.