sonible smart:EQ 4 is an AI-assisted equalizer built around one clever idea: instead of treating each channel in isolation, it can analyze up to ten tracks together and carve space so they stop fighting for the same frequencies. That cross-channel unmasking is the plugin's real reason to exist, and it's where smart:EQ 4 pulls ahead of ordinary equalizers.
It excels at the tedious part of mixing. Drop instances on your kick, bass, guitars, and vocal, group them, and the plugin maps who owns which part of the spectrum and applies complementary moves so nothing gets buried. The AI filter also handles single-track cleanup, detecting tonal imbalances against instrument, vocal, and genre profiles or a custom reference. Dynamic, per-band processing reacts to the source rather than clamping down statically, and the interface is clean and legible.
The trade-off is that this is an assistive tool, not a substitute for judgment. Lean on the auto-suggestions too hard and mixes drift toward a competent but generic average, sanding off the character you may have wanted. Treat its output as a smart starting point and dial it back to taste, and the results are strong. There's also a practical cost: several analyzing instances on a big session add up on the CPU meter.
Value is the honest sticking point. At €129 it's priced like a premium processor, and the cross-channel workflow has to earn that over the capable stock EQ in every DAW. Its listed alternatives here aren't direct rivals — Crystalline is a reverb, while AmpliTube 5 and Guitar Rig 7 are amp-and-effects suites — so smart:EQ 4 mostly competes against manual EQ discipline and other intelligent tools like sonible's own smart:EQ line and Soothe2-style resonance processors.
Choose it if you routinely wrestle crowded arrangements and want fast, musical spectral separation. If you mostly EQ one track at a time, a good stock EQ will get you most of the way for free.