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Item #: SCP-XXXX
Object Class: Awaiting Classification - Containment impossible.
Official Notice: At the request of Dr. █████, all personnel researching SCP-XXXX are being asked to research effective methods for using SCP-XXXX-4 as a potential auditory memetic kill agent.
Official Notice #2: All names listed below have been classified due to several personnel requesting access to SCP-XXXX-3. Access is need based, and frivolous requests will be ignored.
Special Containment Procedures: Due to the fact that SCP-XXXX is a psycho-acoustic anomaly, there is no physical way of containing it. There are, however, measures enacted to protect researchers from it's effects while performing experiments with it:
Two speakers, capable of accurately reproducing low frequencies, are installed in the center of an anechoic chamber. These speakers will be controlled remotely using a synthesizer program from the observation room. This chamber should only have one camera, and it should be embedded in the acoustic-deadening material, as to reduce the amount of variance in vibrations inside the chamber.
Description: SCP-XXXX is a psycho-acoustic anomaly that manifests when the frequencies 23.75 Hz and 24.5 Hz are sounded together from two separate speakers. Exposure to this specific pair of frequencies cause various psychological, and in some cases, physical effects.
The effects of SCP-XXXX differ based on the waveform that is used to recreate the frequencies.
Four different types of waveform have been tested so far; Sine, Square, Triangle, and Sawtooth. In these different forms, SCP-XXXX will be referred to as follows; SCP-XXXX-1 (Sine), SCP-XXXX-2 (Square), SCP-XXXX-3 (Triangle), and SCP-XXXX-4 (Sawtooth).
Research Notes:
Premise: Subjects were placed in the anechoic chamber and exposed to four variants of SCP-XXXX.
When subjects were exposed to SCP-XXXX-1, they expressed feelings of depression and dread. These effects subsided shortly after the test concluded.
When exposed to SCP-XXXX-2, subjects claimed that they were being watched. The heart rate of each subject raised by an average of 40%, and displayed signs of paranoia. After exposure to SCP-XXXX-2 ended, none of the subjects could accurately describe what they claimed was watching them. This time the effects lasted from 2-3 hours.
SCP-XXXX-3 had the most positive results. Subjects claimed that they felt strangely comfortable and slightly lethargic while exposed to SCP-XXXX-3. One subject claimed that he felt like he was in a comfortable chair, despite the fact that he was standing while being tested. The effects of SCP-XXXX-3 remained for about 30 minutes after the test's conclusion. (One subject was exposed to SCP-XXXX-3 again, after he was being unresponsive in an interview after testing with SCP-XXXX-2.)
SCP-XXXX-4 proved to be fatal, and only two test subjects have been tested. After six seconds of exposure to SCP-XXXX-4, the first subject went into cardiac arrest. The second subject threw himself into the chamber door, and after hyperventilating for 19 seconds, went into cardiac arrest as well.
Additional Notes:
Researchers also concluded that relatively similar frequencies (such as 24 Hz and 25 Hz) had no effect on any test subjects. However, when the original frequencies were multiplied by varying factors, it was found that higher frequencies of the same ratio (such as 196 Hz and 190 Hz) had effects similar to the original frequencies, but they were much milder. Most notably SCP-XXXX-4-1, which caused migraines instead of cardiac arrest.
Discovery: The Foundation was made aware of SCP-XXXX in 19██ when a musician in [REDACTED], Ohio was experimenting with Low Frequency Harmonic Polyrhythms. The musician was discovered dead from cardiac arrest in his home by a police officer who was investigating the house because of a noise complaint from a neighbor.
When Foundations arrived at the musician's home, his speakers were found destroyed, but investigating Foundation agents could not determine if the damage was caused by the musician, or from the high sound pressure from SCP-XXXX. The speakers are now being stored for repair and further testing at Site-██.
Addendum: Interview with subject D-181█
Opening Statement: Interview taken place after exposure to SCP-XXXX-1.
Interviewer: Dr. ███████
Interviewed: D-181█
<Begin Log 1:14 PM>Dr. ███████: "So what exactly happened when you heard the sound?"
D-181█: "Well, it didn't really do anything at first, but then I.. I felt.."
Subject stares blankly and trails off for a moment.
Dr. ███████: "Felt what?"
D-181█: "I felt like I was in high school again."
Dr. ███████: "What do you mean by that?"
D-181█: "Well.. like the way I hated coming because of the people there."
Dr. ███████: "So you felt anxious?"
D-181█: "Not so much anxious- like there was a huge weight on me. I felt very pessimistic about my life.. In the sound room I mean.
Dr. ███████: "So you would say you felt depressed, and that you felt the same dread you felt going to school?
D-181█: "Exactly, yeah."<End Log, 1:18 PM>
Closing Statement: After a psychological evaluation, Subject D-181█ showed no signs of lasting psychological effects.
Addendum 2: Interview with subject D-186█ - (Second round of testing.)
Opening Statement: Interview taken place after exposure to SCP-XXXX-2.
Interviewer: Dr. ███████Interviewed: D-186█
<Begin Log 2:35 PM>Dr. ███████: "So during the test, you said something was watching you?"
No response.
Dr. ███████: "What was watching you?"
D-186█: "I don't know, man, I'm still kinda shaky, you know?"
Dr. ███████: "That's okay. You know, the only thing in that chamber besides the speakers
was you."D-186█: "Are you sure?"
Subject begins to quiver.
D-186█: "I can still feel that thing breathing down my neck."
Subject is shaking more violently.
Dr. ███████: To Research Assistant: "Put him in with SCP-XXXX-3, maybe that will get him to calm down."
<End Log, 2:37 PM>
Closing Statement: Subject D-186█ was taken back into the chamber and was exposed to
SCP-XXXX-3, and he subsequently acted less distressed by his experience with SCP-XXXX-2.
Addendum 3: Interview with subject D-189█
Opening Statement: Interview taken place after exposure to SCP-XXXX-3.
Interviewer: Dr. ███████
Interviewed: D-189█
<Begin Log 2:57 PM>Dr. ███████: "So how did you feel after exposure?"
D-189█: "It was mostly pretty nice."
Dr. ███████: "Mostly?"
D-189█: "Well, I felt a little.. slow, afterward."
Dr. ███████: "You felt like you couldn't do much?."
D-189█: "Yeah, it was like I was sitting in a big rocking chair."
Dr. ███████: "That's interesting." To Research Assistant "Maybe we can reuse SCP-XXXX-3 for therapeutic reasons."
<End Log, 2:59 PM>
Closing Statement: Subject D-186█ was taken back into the chamber and was exposed to
SCP-XXXX-3, and he subsequently acted less distressed by his experience with SCP-XXXX-2.
Official Notice #3: Testing with SCP-XXXX-1, SCP-XXXX-2, and SCP-XXXX-4, is hereby prohibited until further notice. However; SCP-XXXX-3 may be used with permission from personnel with Level-4 clearance for therapeutic purposes.
