Echo Key Beam System
The main components of this system are the Echo Key Beam Emitter and the Echo Gate. The lock on the Echo Gate can be opened with a series of four consecutive focused sounds of particular pitches, and the order can be determined by shooting the Echo Gate lock with the Annihilator Beam. Each emitter is tuned to fire a blast of sound in a particular pitch and must be activated in the predetermined series to override the locks on the Echo Gate.
Echo Key Beam Emitter
Echo Key Beam Emitters work by firing blasts of focused sound at an Echo Gate lock when activated by a shot from the Annihilator Beam. When the emitters are activated in the correct sequential order the Echo Gate is unlocked.
The sonic security systems that protect Echo Gates are locked by a combination of four sonic locks. Shooting the Echo Gate with the Annihilator Beam plays back the combination for anyone wearing sonic detection gear, and then the emitters can be used to enter the correct sequence.
- "Object scan complete. This is an Echo Key Beam system. Sonic detection gear needed to interface with this system. Shoot the Echo Key Beam emitter with a sonic pulse to activate it. It will then fire a blast of focused sound at an Echo Gate lock." —Scan Data (Metroid Prime 2: Echoes)
- "This Echo Gate uses a sonic security system. Sonic detection gear needed to interface with this system. Shoot the Echo Gate with a sonic pulse to learn the combination of its sonic locks. Unlock the locks in this sequence to advance." —Scan Data (Metroid Prime 2: Echoes)