Audio & Video Evidence Review Flashcards

Which type of microphone pickup pattern is generally preferred for EVP sessions to minimize room reverb and focus on nearby sounds?

Answer: Cardioid

A cardioid microphone captures sound primarily from the front while rejecting much of the reverb and noise coming from the sides and rear, making it effective for focused EVP capture.

When timestamping video evidence, why is syncing all cameras to a single time reference critical?

Answer: It allows cross-referencing of anomalies across multiple cameras to confirm or debunk them

A shared time reference allows investigators to determine whether an anomaly captured on one camera corresponds to anything on other cameras at the exact same moment.

What is the 'stone tape theory' and how does it relate to audio/video evidence review?

Answer: A theory that building materials absorb and replay past events as sounds or images, used to contextualize unexplained audio/video anomalies

The stone tape theory proposes that materials like stone can record and later play back past events; investigators sometimes use this framework to contextualize audio or visual anomalies in old stone buildings.

A video shows a figure that disappears when the investigator enters the room but was clearly visible on the monitor. What is the most likely technical explanation?

Answer: Monitor display lag caused the investigator to see a delayed image that had already resolved

Display lag (latency) on monitors connected to live cameras can show an image that is several frames behind real time, making it appear as though something vanished upon the investigator's entry.

Which software feature is most useful for isolating a suspected EVP buried within constant low-frequency rumble?

Answer: A high-pass filter set to cut frequencies below the rumble threshold

A high-pass filter removes low-frequency rumble below a chosen cutoff point, allowing higher-frequency voice content to be heard more clearly.

What is 'matrixing' in the context of video evidence review?

Answer: The brain's tendency to find familiar shapes (like faces) in random visual patterns such as shadows or textures

Matrixing is the human brain's propensity to recognize familiar shapes, particularly faces, within random patterns; this can lead investigators to misidentify shadows or textures as apparitions.

Which practice BEST reduces contamination of audio evidence during a multi-investigator EVP session?

Answer: Using a call-and-response protocol where only one investigator speaks at a time and each statement is verbally tagged with the speaker's name

A structured call-and-response protocol with verbal speaker tags creates a clear audio record that allows reviewers to attribute every known voice, making unidentified voices stand out.