Technicolor DTMF sequences: Difference between revisions

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Many SP-mode videotapes duplicated at Technicolor Videocassette beginning in mid 1989 and ending in mid 2003 included a sequence of DTMF phone-dial tones at the start and/or end of the tape. On certain tapes with this sequence, a faint sound of extra tones precedes it. It is not yet known exactly what each tone in the sequence indicates, except there's usually a pause between the first and second tones, the second tone is always 1, the third tone is always #, and the fourth tone is always D. This sequence was used to encode information on the master tape by providing information on settings such as format, running time, audio level balance, volume control, etc. to automatic videotape duplication machines. This allowed better replication of the master tapes that were copied onto the formats the videotapes were released in.
Many videotapes duplicated at [[Technicolor Video Services]] in Livonia using either industrial duplicators or Otari TMD systems, beginning in 1989 and ending in 2006, included a sequence of DTMF tones at the start and/or end of the tape. It is not yet known exactly what each tone in the sequence indicates, except there's usually a pause between the first and second tones, the second tone is always 1, the third tone is always #, and the fourth tone is always D. This sequence was used to encode audio and video on the master tape by providing information on settings such as format, running time, audio level balance, volume control, etc. to the duplication machines, allowing better replication. On most tapes, the tones are audible on the left channel of the hi-fi audio track. However, on some tapes, the tones are audible either on the right channel of the hi-fi track or exclusively on the linear audio track. Disney videotapes are the most notable tapes to use these sequences.


For a list of tapes using variations of these sequences, see [[Technicolor test patterns]].
==Oddities About This Sequence on Certain VHS Tapes==

* On certain pressings of CBS/Fox releases from 1989-1990, this sequence occurs during the still-framed 1983-1999 Fox FBI warning screen/1984-2000 CBS/Fox Video logo combo that likely occured at the start of those pressings due to some sort of processing error.
== Video examples ==
* On some VHS tapes released by Buena Vista Home Entertainment, this sequence occurs during the company's FBI warning screens, most notably on couple pressings of the 1991 VHS releases of Disney's "The Reluctant Dragon" and the first few Walt Disney Studio Film Collection titles.
# [https://www.youtube.com/watch?v=CrMiiNdjnbY Spooky!! Phone dialing sound on Disney VHS tapes!?]
* Usually, this sequence is heard in the left audio channel, but occasionally, it could be on the right (most notably on certain pressings of the 1993 VHS of Disney's "Pinocchio"). Funnily enough, some YouTube users falsely label this sequence as coming from the specific videotape player model, rather than the specific videotape itself.
# [https://www.youtube.com/watch?v=0LyLq_cmetM VHS Phone Dialing Sound]
# [https://www.youtube.com/watch?v=-6ygY98jq64 VHS Dialing Sound Effect]
# [https://www.youtube.com/watch?v=hzv3ZQQF78A&list=PLKcNH5J_u70wzF2JxfsCCuB5g1-7V13XW&index=39 Creepy Phone Dialing in the beginning of Disney VHS tapes]

Latest revision as of 14:59, 6 May 2024

Many videotapes duplicated at Technicolor Video Services in Livonia using either industrial duplicators or Otari TMD systems, beginning in 1989 and ending in 2006, included a sequence of DTMF tones at the start and/or end of the tape. It is not yet known exactly what each tone in the sequence indicates, except there's usually a pause between the first and second tones, the second tone is always 1, the third tone is always #, and the fourth tone is always D. This sequence was used to encode audio and video on the master tape by providing information on settings such as format, running time, audio level balance, volume control, etc. to the duplication machines, allowing better replication. On most tapes, the tones are audible on the left channel of the hi-fi audio track. However, on some tapes, the tones are audible either on the right channel of the hi-fi track or exclusively on the linear audio track. Disney videotapes are the most notable tapes to use these sequences.

For a list of tapes using variations of these sequences, see Technicolor test patterns.

Video examples[edit]

  1. Spooky!! Phone dialing sound on Disney VHS tapes!?
  2. VHS Phone Dialing Sound
  3. VHS Dialing Sound Effect
  4. Creepy Phone Dialing in the beginning of Disney VHS tapes