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SCP-5689-1 (left) and SCP-5689-2 (right) in containment.
Item #: SCP-5689
Object Class: Euclid
Special Containment Procedures: SCP-5689 is to be stored in a 30cm x 30cm x 30cm container lined with sound-absorbent material at Site-██. Anyone outside of Foundation personnel who hears any sound emitted by SCP-5689-1 are to be administered Class-B amnestic. Any experimentation involving SCP-5689 requires approval from at least 2 personnel with level 3 security clearance and must be done at least 5 kilometres away from any person other than the ones directly involved in the experiment. Any audio equipment used when testing SCP-5689 must automatically deactivate when sound emitted by SCP-5689-1 reaches 130 decibels.
Description: SCP-5689 consists of 1) SCP-5689-1, a wooden chime approximately 18cm in length with a steel rod of the same length attached and secured onto the top with 2 latex straps fit into notches along the wood and steel, and 2) SCP-5689-2, a latex mallet approximately 13.5cm in length attached with a latex ball approximately 2cm in diameter.
When attempting to use SCP-5689-2 strike the steel rod on SCP-5689-1 with a force of 10N, SCP-5689-1 will emit a sound approximately 40 db in volume. Sound wave analysis shows that sound waves emitted by SCP-5689-1 are consistent with graphs generated by the mathematical formula [REDACTED].
After a period of approximately 26 seconds, sound emitted by SCP-5689-1 will gradually increase at approximately 0.6 db per second until it renders all sapient entities capable of hearing the sound unconscious, cause their hearing organs to fail, or produce any event that will prevent them from hearing the sound. The sound emitted by SCP-5689-1 will then gradually fade at approximately 0.6 db per second until completely vanishing. The distance away from SCP-5689-1 does not seem to affect this effect.
SCP-5689 was created when Dr. ███████ refined a chime and a mallet with similar features to SCP-5689 in SCP-914 at the "very fine" setting. Dr. ███████ initially thought that he had mistakingly refined the objects at the "1:1" setting, but when Dr. ███████ struck the steel rod on SCP-5689-1 with SCP-5689-2, [DATA EXPUNGED]. Dr. ███████ was administered Class-C amnestic and returned to his research position.
Incident 5689-1: On 19/4/████, D-3625 attempted to breach containment by using SCP-5689 as a distraction. Sound emitted by SCP-5689-1 peaked at ███ db, killing 7 personnel and injuring 31 others before multiple armed guards equipped with sound insulation gear re-contained SCP-5689 and MTF Nu-7 officers found and terminated D-3625. Afterwards, everyone at Site-██ was administered Class-A amnestic.
SCP-5689 Testing Log
Document # 5689-1: Initial Test Log
Subject: D-4367
D-4367 was given standard recording gear, led 10 kilometres away from Site-██ by Agent ██████, immobilized, and instructed to strike the steel rod on SCP-5689-1 with SCP-5689-2. Agent ██████ was instructed to flee upon D-4367 striking SCP-5689-1 with SCP-5689-2.
Result: Upon being struck, SCP-5689-1 emitted an initial sound of approximately 36 db. Later analysis showed that SCP-5689-1 was struck with a force of approximately 8.9N. After approximately 28 seconds, the sound emitted by SCP-5689-1 gradually increased by approximately 0.5 db per second for ███ seconds, reaching a sound of an estimated ███ decibels before video feed cuts out.
A team of 5 agents were sent to D-4367's last known location to recover D-4367. They found D-4367 dead, apparently from aorta rupture. Autopsy of D-4367 showed most of his arteries ruptured and his cells [DATA EXPUNGED].
"SCP-5689 could potentially be useful in sound testing." -Dr. █████
Further testing arranged.
Document # 5689-2
Purpose: To determine whether SCP-5689-1's effects could be triggered by anything other than SCP-5689-2.
Subject: D-6892
D-6892 was given standard recording gear and an ordinary mallet, led 8 kilometres away from Site-██ by Agent ██████, immobilized, and instructed to strike the steel rod on SCP-5689-1 with the ordinary mallet. Agent ██████ was instructed to flee upon D-6892 striking SCP-5689-1 with the ordinary mallet.
Result: Upon being struck by the ordinary mallet, SCP-5689-1 emitted an initial sound of approximately 38 db. Later analysis showed that SCP-5689-1 was struck with a force of approximately 9.5N. After approximately 19 seconds, the sound emitted by SCP-5689-1 gradually decreased by approximately 0.4 db per second until completely vanishing. Afterwards, D-6892 was returned to the site and administered Class-B amnestic.
Conclusion: SCP-5689-1's effects will only take place if its steel rod is struck by SCP-5689-2.
"I wonder if the opposite is true." -Dr. █████
Document # 5689-3
Purpose: To determine whether SCP-5689-2 could trigger an effect on anything other than SCP-5689-1.
Subject: D-5863
D-5863 was given standard recording gear and an ordinary chime the same model as SCP-5689-1, led 9 kilometres away from Site-██ by Agent ████████, immobilized, and instructed to strike the steel rod on the ordinary chime with SCP-5689-2. Agent ████████ was instructed to flee upon D-5863 striking the ordinary chime with SCP-5689-2.
Result: Upon being struck by SCP-5689-2, the ordinary chime emitted an initial sound of approximately 41 db. Later analysis showed that the ordinary chime was struck with a force of approximately 10.3N. After approximately 21 seconds, the sound emitted by the ordinary chime gradually decreased by approximately 0.3 db per second until completely vanishing. Afterwards, D-5863 was returned to the site and administered Class-B amnestic.
Conclusion: SCP-5689-2 can only trigger an effect on SCP-5689-1.
Document # 5689-4
Purpose: To determine what happens after no sapient entities are capable of hearing the sound emitted by SCP-5689-1.
Subject: Dr. ███████ (volunteer)
Prior to the experiment, Dr. ███████ requested the use of 1) a sound insulation headset and 2) a robotic arm. Both requests were approved.
Dr. ███████ was given the requested equipment and standard recording gear. He walked 9km away from Site-██, attached SCP-5689-2 to the robotic arm, and used the robotic arm to strike the steel rod on SCP-5689-1 with SCP-5689-2 with a pre-programmed force of 10N. After approximately 60 seconds. Dr. ███████ put on the sound insulation gear.
Result: Upon being struck by SCP-5689-2, SCP-5689-1 emitted an initial sound of approximately 40 db. After a period of approximately 26 seconds, the sound emitted gradually rose at approximately 0.6 db per second, reaching a volume of approximately 60 db before Dr. ███████ put on the headset. The sound emitted then gradually faded at approximately 0.6 db per second until completely vanishing. Dr. ███████ returned to Site-██ and was debriefed. Dr. ███████ then returned to the site and was debriefed. Amnestics are not issued.
