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Item #: SCP-XXXX
Object Class: Safe
Special Containment Procedures: SCP-XXXX is to be kept in a secure double-lock safe at Site-XX. Under no circumstances should SCP-XXXX be inserted into any device capable of playing audio from cassette tapes, unless for research purposes, and should not be handled by anyone without level three (3) clearance or higher. Testing of SCP-XXXX should be preformed in a soundproof room on a standard audio cassette player, and audio recording of audio from SCP-XXXX should be tested for anomalous effects. All personnel should be informed of SCP-XXXX's properties. SCP-XXXX's storage container is not to be opened by anyone without level three (3) clearance or higher.
Description: SCP-XXXX is an audio cassette of standard weight and dimensions. Despite containing roughly 60 minutes of cassette tape, the recording itself has not yet been observed to end. Instead of running out of tape at 60 minutes as a non-anomalous cassette tape should, when SCP-XXXX is played, tape from the supply reel has been observed to dispense an infinite source of tape, and tape fed to the take-up reel has been observed to disappear as more tape is taken from the supply reel.
Audio from SCP-XXXX resembles a recorded laugh track not unlike those used in television comedies. At time of containment, audio filtering of SCP-XXXX revealed to contain the laughter of approximately seven (7) voices. After playing audio from SCP-XXXX for exactly 13 seconds, more voices can be heard, the number of new voices added depending on the number of listeners within auditory range of SCP-XXXX. Laughter added to the audio resembles that of the listener(s). Subjects exposed to audio from SCP-XXXX for more than 13 seconds report a sense of unease and paranoia that increases in intensity as the audio continues. Recordings of SCP-XXXX via other means of recording do not possess the same anomalous effects, however, subjects whose laughter had been "captured" via SCP-XXXX will still feel slight unease at hearing their laughter on a non-anomalous recording.
Addendum: SCP-XXXX was found at the ████ Studio in ████, ██, USA on ██/██/19██. SCP-XXXX was originally found by two studio members in a cardboard box containing 20 other cassette tapes of similar make and model. Said studio members were playing the cassette tapes when SCP-XXXX's anomalous effects were discovered. Word of SCP-XXXX passed to three (3) other studio members before Agent ████, under the guise of an editor employed by the studio, confiscated SCP-XXXX and contacted the Foundation. Studio members with knowledge of SCP-XXXX were administered Class-A amnestics and returned to studio work.
Test A - ██/██/19██
Subject: D-4757
Procedure: D-4757 ordered to play SCP-XXXX on a standard cassette player in a sound-proof room. Non-anomalous recording studied after test.
Results: After approximately 13 seconds, subject reports hearing their own laughter among the others, despite not laughing at all. Audio played for 1 minute 37 seconds before D-4757 requested it be turned off. Request granted.
Analysis: After 13 seconds the laughter of the listener is added to the audio.
Test B - ██/██/19██
Subject: One canis familiaris1 subject
Procedure: SCP-XXXX played remotely in the vicinity of the subject in a sound-proof room. Non-anomalous recording studied after test.
Results: Audio remained the same, no additions made to audio.
Analysis: SCP-XXXX only captures human laughter
Test C - ██/██/19██
Subject: One Cacatua tenuirostris2 subject
Procedure: SCP-XXXX played remotely in the vicinity of the subject in a sound-proof room. Subject trained to mimic human laughter. Non-anomalous recording studied after test.
Results: After 13 seconds, laughter resembling that of the Cockatoo reported to be added to the audio.
Analysis: SCP-XXXX can capture laughter from non-human sources.
Test D - ██/██/20██
Subject: D-2488
Procedure: Subject diagnosed with neurogenic mutism since childhood, communicates via ASL. D-2488 ordered to play SCP-XXXX on a standard cassette player in a sound-proof room. Non-anomalous recording studied after test.
Results: After 13 seconds, subject reports hearing a new laugh resembling that of a child's added to the others. Subject becomes increasingly distressed and shuts the audio off after 32 seconds. D-2488 refuses to continue the recording.
Analysis: Laughter is captured from any sentient being physically capable of laughter at any point in life.
Test E - ██/██/20██
Subject: Human corpse (recently deceased)
Procedure: SCP-XXXX played remotely in the vicinity of the subject in a sound-proof room. Non-anomalous recording studied after test.
Results: After 13 seconds, laughter resembling that of the subject in life is added to the audio.
Analysis: Laughter from sentient beings added regardless of life or death.
