Upgrading the sonic resonator to the feedback resonator in Subnautica 2 is a major milestone in progression. The regular resonator only works at close range, which makes it impossible to deal with bloom cankers that wrap themselves in unbreakable petals when they sense a threat approaching. You’ll need to get a blueprint for it first, though, which takes some digging around, and you also need some intermediate crafting materials to make it.
Below, we explain how to upgrade your sonic resonator in Subnautica 2 and where to find the feedback resonator blueprint.
[Ed. note: Before you dive in, be sure to open the character menu and enable all landmark signals. This will make it easier to spot the locations mentioned in this guide.]
How to find the feedback resonator blueprint in Subnautica 2
You need to scan two feedback resonators to unlock the blueprint, and there’s a few of them scattered around the area east of the Alien Ruins. One of them is in the Therapy Room section of the Cicada wreckage, which is on a cliff about 300 meters east-northeast of Iso’s Blackbox. Enter the wreckage from the eastern side, and you’ll find the feedback resonator at the far end of the room near a damaged door.
A second feedback resonator is lying in the sand around an abandoned research platform, tucked away in a brightly lit alcove with quite a lot of silver nodes nearby. It’s just south the Axum metal farm, about 870 meters east of the Alien ruins and 420 meters deep, so you’ll need a depth module for your tadpole. There are no oxygen tunics nearby, and even with the second air tank upgrade, you’d be hard-pressed to get here and back to the surface or a safe room before your oxygen runs out. So don’t try that.
There’s a third feedback resonator in the metal farms, 20 meters east of Zip’s Blackbox (2), where the troilite nodes spawn. If you encounter a bug that won’t let you scan one of the other resonator pieces, you can hopefully get that one instead and obtain the blueprint.
How to craft the feedback resonator in Subnautica 2
The feedback resonator blueprint lives in the modification station as a “prototype tool modification.” Crafting it requires:
The feedback resonator replaces your sonic resonator in the toolbar, and it functions basically the same way. Hold the button to charge a blast, aim at your target, and release. The feedback resonator’s charged bubble travels a short distance before exploding. It can be tough to judge the distance, but if you’re within range of the target, the charge icon will turn green.
If you’re starting out in Subnautica 2, we have a plethora of guides to help you navigate the deep blue sea. Our Subnautica 2 beginner’s guide will set you off in the right direction and our base building tips will assist in planning out your sprawling base. Don’t forget to stock up on food and water, too. (And if you want to get fancy with your food, you’ll want salt!)
If you need help finding materials, we explain how to get the sonic resonator, which you’ll want to mine tons of materials. We have guides on where to find these resources, like lead, sulfur, copper, quartz, and gold.









