Fractal Audio AM4 Amp Modeler: 240+ Amps and Cygnus X-3 for $699
The Fractal Audio AM4, released in 2025 at $699, brings Axe-Fx III-level amp modeling into a compact pedalboard format. With 240+ amp models powered by the Cygnus X-3 algorithm, 45+ DynaCabs, 77+ drive models, 79+ reverbs, and 150+ additional effects, the AM4 delivers Fractal’s renowned modeling quality at a price point that was previously unthinkable. Four channels per preset with gapless switching make it a serious live performance tool, while the included AM4-Edit software provides deep editing from a computer.
Fractal Audio AM4 Specifications
| Specification | Detail |
|---|---|
| Type | Amp Modeler/Multi-Effects |
| Street Price | $699 USD |
| Amp Models | 240+ |
| Algorithm | Cygnus X-3 |
| DynaCabs | 45+ |
| Drives | 77+ |
| Reverbs | 79+ |
| Additional Effects | 150+ (chorus, comp, flanger, phaser, tremolo, wah, EQ, gate, filter) |
| Channels | 4 per preset, gapless switching |
| USB | 4×4 audio interface |
| Software | AM4-Edit included |
Cygnus X-3 Modeling
The AM4 uses Fractal’s Cygnus X-3 modeling algorithm, which performs component-level physical modeling of amplifier circuits. Rather than using simplified approximations, Cygnus X-3 models the behavior of individual tubes, resistors, capacitors, and transformers, creating virtual amplifiers that respond to playing dynamics, guitar volume changes, and pickup selection exactly like their real-world counterparts. This is the same modeling engine that powers the flagship Axe-Fx III.
DynaCabs: Beyond Static IRs
The 45+ DynaCabs go beyond traditional impulse responses by modeling speaker behavior dynamically. Where a static IR captures a speaker at one moment in time, DynaCabs model how the speaker responds to different frequencies, volumes, and transients, providing a more realistic and three-dimensional cabinet tone that changes with your playing in real time.
Who Should Buy the Fractal Audio AM4
The AM4 is the entry point into the Fractal ecosystem for players who want world-class modeling at a competitive price, pedalboard users who need compact Axe-Fx-quality tone, and musicians who want 240+ amp models with gapless switching for live performance.
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Frequently Asked Questions
Is the AM4 the same quality as the Axe-Fx III?
The AM4 uses the same Cygnus modeling algorithm as the Axe-Fx III. The amp models and effects are identical in quality; the Axe-Fx III offers more simultaneous processing power and routing flexibility.
See the Axe-Fx III Firmware 28 or FM9 updates.