EZbass is Toontrack's virtual bassist, and it approaches bass the way its sibling EZdrummer approaches drums. The goal is not to hand you a blank sampler and wish you luck. It is to write, play and produce a convincing bass part with as little friction as possible. That framing is the key to judging it.
Where EZbass excels is workflow. The audio-to-MIDI engine can listen to a guitar riff, a vocal line or even a kick pattern and generate a matching bassline you can then edit. Its groove library is deep, and the "follow" feature can lock the bass to an existing track's chords and rhythm. Drop it under an EZdrummer beat or an EZkeys progression and you get a coherent low end in minutes. For songwriters who think in parts rather than samples, this is genuinely liberating.
The sampled instruments themselves are strong. Both the modern Alembic-style bass and the vintage Fender Jazz were multi-sampled with finger, pick and slap articulations, tuneable down to A0, plus amp, DI and tone-shaping controls. They sound authentic in a mix.
The trade-off is scope. The core library ships with only two basses, and broadening your palette means buying EBX expansions or MIDI packs, so the real cost creeps above the $179 sticker. EZbass is also unapologetically a realistic-electric-bass tool. It is not built for aggressive synth bass or sound design, and power users may find the performance engine more prescriptive than a raw Kontakt instrument.
Against its alternatives, that focus sharpens. Kontakt 8 is far more flexible but demands you build everything yourself. ATLAS 2 is a sample-finder, not a playable instrument. EZkeys 2 shares this exact philosophy for keys, and the two pair beautifully.
Choose EZbass if you want believable bass parts written for you and already lean on Toontrack's ecosystem. Look elsewhere if you need synth bass or total sampler freedom.