Revision 4

The Feedback Resonator is an upgraded Sonic Resonator in Subnautica 2. Where the base tool releases a pulse around the player, the upgraded version fires a projectile that carries the same blast to a target at range. Its in-game description calls it a modified sound amplifier that uses a bacterial feedback system to analyze and shatter hardened biomolecules, which is a fair summary of what it is for.

Like the Bioscanner, it is one of the tools built by grafting Axum technology onto standard-issue Alterra hardware, and the PDA note that accompanies it is openly uneasy about the trend.

How to Unlock It

The blueprint unlocks after scanning two separate Feedback Resonator fragments in the world. One sits in a Cicada wreck interior behind a charred door that has to be opened with the Repair Tool, and another lies out in the open in a root-canyon area near a yellow pool. Further fragments are recorded deeper in the Karakorum metal farms and in a silver mine on their edge, several hundred metres down, so the upgrade is comfortably a mid-to-late Early Access unlock rather than an early one.

Recipe

The upgrade is assembled at a Modification Station, not the standard Fabricator, and it consumes the base tool.

Using It

• Ranged blast. The tool shoots a projectile in the aimed direction that detonates on contact, with an effective range of roughly 25 metres before it dissipates in a small controlled burst.

• Armored Bloom growths. The main reason to build it. Hardened Bloom cankers can be broken from a distance instead of at arm's length, which removes the need to swim into an infested pocket to clear it. See The Blight for what the infestation is and why it spreads.

• Everything the base tool does. It keeps the mining and creature-deterrence behavior of the Sonic Resonator, so it replaces rather than supplements the original in most loadouts.

The projectile also works as a ranged deterrent: it stuns exposed Sandspears, interrupts a Bullethead mid-attack, and knocks Electric Geordies off a vehicle hull without closing the distance.

Since the Buddy System update on August 19, 2026, a hit stuns the creature rather than making it flee, so the target is held in place for a moment instead of scattering. That makes the tool more useful for clearing a path and for buying time around a vehicle, and it pairs with the Sonic Resonator stun, which the same update extended to ten seconds.

Related Pages

• Sonic Resonator

• Tools and Equipment

• Bioscanner

• The Blight