# Old movies and TV shows: audio "bleeding through"? **URL:** \ **Category:** Cafe Society\ **Created:** [January 1, 2012, 2:49am UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005 "2012-01-01T02:49:28Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![KneadToKnow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kneadtoknow/32/3999_2.png) [@KneadToKnow](https://boards.straightdope.com/u/KneadToKnow)\ **Post date:** [January 1, 2012, 2:49am UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/1 "2012-01-01T02:49:28Z")
I’m watching the _Twilight Zone_ marathon on Syfy and noticing something that I’ve noticed with other shows and movies of a certain age: If there’s a quiet moment followed by dialogue or especially loud sounds, you can very often hear a faint “echo” of the coming audio a few seconds before it actually happens. I’m sure I’m describing this badly, but to the extent that you can understand what I’m talking about, what causes this? ---
**Author:** ![rowrrbazzle](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rowrrbazzle/32/414_2.png) [@rowrrbazzle](https://boards.straightdope.com/u/rowrrbazzle)\ **Post date:** [January 1, 2012, 4:29am UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/2 "2012-01-01T04:29:56Z")
It’s called print-through. [Print-through - Wikipedia](http://en.wikipedia.org/wiki/Print-through) > [@](#): > > Print-through (sometimes referred to as bleed-through) is a generally undesirable effect that arises in the use of magnetic tape for storing analogue information, in particular music. > > The proximity of layers of tape on the spools of a cassette or reel to reel tape causes a weak imprint of magnetic information to be transferred to adjacent layers, effectively shifting a copy of the signal backwards and forwards along the tape. This can sometimes be heard as pre- or post-echo. [1] Thinner tapes (designed for longer running times, since more tape can be held on the same spool) are more prone to the effect than thicker tapes, and tapes held in storage for a long period or exposed to a weak magnetic field can show pronounced print-through. Digital tapes are not affected in the same manner as the imprint is generally too weak to change the state of bits recorded on adjacent layers of the tape. ---
**Author:** ![rowrrbazzle](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rowrrbazzle/32/414_2.png) [@rowrrbazzle](https://boards.straightdope.com/u/rowrrbazzle)\ **Post date:** [January 1, 2012, 4:37am UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/3 "2012-01-01T04:37:03Z")
Hit enter too soon. I had an LP set (Handel’s Messiah, Hermann Scherchen conducting, 1954, monophonic) with that echo in a couple of spots. Yes, the master tape itself had print-through. It was still there on the CD reissue because even with digital techniques it’s impossible to remove without affecting the main sound. (On that recording there are actually a couple of rough spots in the performance and editing as well. I wonder what problems there were prior to pressing the record, but I can’t find any detailed information.) ---
**Author:** ![campp](https://avatars.discourse-cdn.com/v4/letter/c/c5a1d2/32.png) [@campp](https://boards.straightdope.com/u/campp)\ **Post date:** [January 1, 2012, 12:47pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/4 "2012-01-01T12:47:55Z")
I’ve always wondered about that part near the end of Whole Lotta Love (Led Zepplin) if that was tape bleed-through or done on purpose. I tend to think bleed-through. It’s where Plant is slowly wailing “Way down inside…Woman…You need it…Love…” or whatever he sings. ---
**Author:** ![panache45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/panache45/32/64_2.png) [@panache45](https://boards.straightdope.com/u/panache45)\ **Post date:** [January 1, 2012, 12:53pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/5 "2012-01-01T12:53:11Z")
Yes, I’ve been noticing this for a long time, and for whatever reason it’s worst with \*Twilight Zone. \* I’m thinking that, especially in the case of voices, it could be removed by a process similar to the removal of vocals in Karaoke. ---
**Author:** ![KneadToKnow](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kneadtoknow/32/3999_2.png) [@KneadToKnow](https://boards.straightdope.com/u/KneadToKnow)\ **Post date:** [January 1, 2012, 3:54pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/6 "2012-01-01T15:54:52Z")
Thanks for the answer! It’s sad to think that if this print-through is present on the broadcast copies of the show, then it’s likely also present on the DVDs. I’d like to think, like **panache45** , that since it is most noticeable during silences, they should be able to mute it better. ---
**Author:** ![Tim\_R.Mortiss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tim_r.mortiss/32/142_2.png) [@Tim\_R.Mortiss](https://boards.straightdope.com/u/Tim_R.Mortiss)\ **Post date:** [January 1, 2012, 5:13pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/7 "2012-01-01T17:13:55Z")
I used to notice that a lot during my old reel-to-reel days. I used really long (and therefore thin) reels. As for the Zep song, I always assumed that was deliberate. At the very least, I’m guessing it was accidentally caused, but deliberately left in. It certainly works for the song. ---
**Author:** ![MWood919](https://avatars.discourse-cdn.com/v4/letter/m/779978/32.png) [@MWood919](https://boards.straightdope.com/u/MWood919)\ **Post date:** [January 1, 2012, 5:15pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/8 "2012-01-01T17:15:07Z")
Thanks for the explanation, people! I’m watching the Twilight Zone marathon, too, and I was getting pretty distracted by that strange, ghostly audio effect I was calling a “pre-echo” (which, as it turns out is a fairly accurate and oft-used term for this phenomenon). Very cool to see a good number of others seeking out the explanation for this weird effect at the same time and to see wiser parties being there to so quickly educate the rest of us. I’m starting to like this Internet thing! Viva la informacion! ---
**Author:** ![banjoDavid](https://avatars.discourse-cdn.com/v4/letter/b/3d9bf3/32.png) [@banjoDavid](https://boards.straightdope.com/u/banjoDavid)\ **Post date:** [January 1, 2012, 6:11pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/9 "2012-01-01T18:11:43Z")
> [@campp](#): > > I’ve always wondered about that part near the end of Whole Lotta Love (Led Zepplin) if that was tape bleed-through or done on purpose. I tend to think bleed-through. It’s where Plant is slowly wailing “Way down inside…Woman…You need it…Love…” or whatever he sings. I think that was caused when Plant sang a scratch vocal track when the whole band played live in the studio, and he overdubbed the new vocal that you hear. The ghost sound is Plant’s voice picked up by mics on the drums and guitar and bass amplifiers. To minimize the effects of print-through in the studio, we kept the taped wound “tails-out.” You had to rewind the tape before using it. The print-through would then happen after the original sound and be masked, rather than a pre-echo sound. Studio tape in the '70’s and '80’s had a thicker plastic base, AGFA 468, AMPEX and 3M tape stocks, to help with the issue. We also recorded at faster speeds, usually 30 IPS (inches per second,) so the errors were minimized. The tape speed of cassettes is 1 7/8 IPS. Most home reel-to-reel recorders used 3 3/4 and 7 1/2 IPS speeds. Running at 30 IPS, a roll of tape lasted for 16 minutes. You had to record over a take of a song, or buy another roll of tape if you wanted to keep your options open when deciding to mix later. Ah, the good ol’ days. Happy new year all! David ---
**Author:** ![Hail\_Ants](https://avatars.discourse-cdn.com/v4/letter/h/dc4da7/32.png) [@Hail\_Ants](https://boards.straightdope.com/u/Hail_Ants)\ **Post date:** [January 2, 2012, 2:48pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/10 "2012-01-02T14:48:51Z")
Growing up in the 70s and watching _ **a lot** _ of TV I started noticing this (definitely in Twilight Zone), and thought I was either psychic or crazy! When I tried to explain it to other, less observant people, they tended to think the latter… ---
**Author:** ![sco3tt](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@sco3tt](https://boards.straightdope.com/u/sco3tt)\ **Post date:** [January 3, 2012, 1:10am UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/11 "2012-01-03T01:10:23Z")
> [@banjoDavid](#): > > To minimize the effects of print-through in the studio, we kept the taped wound “tails-out.” I once worked under a Production Director who believed that gravity influenced print-through, so insisted that we shelve all our reels horizontally rather than vertically to minimize its effect. It sounded ridiculous to me but I went along with the practice just to humor him. Thankfully he never made us rewire the studios with Monster cable or paint the edges of all our CDs with green Sharpies. ---
**Author:** ![Dave\_Labrecque](https://avatars.discourse-cdn.com/v4/letter/d/db5fbb/32.png) [@Dave\_Labrecque](https://boards.straightdope.com/u/Dave_Labrecque)\ **Post date:** [June 8, 2019, 1:52pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/12 "2019-06-08T13:52:49Z")
Cool to notice the echo (both pre- and post- on this current episode of Twilight Zone I’m watching: S1E36 “A World Of His Own” at about 18:33 on the word “No!”) and then find this old post. I’m trying to decide if this print-through happened on the original production tape (Nagra type reel-to-reel, I’d guess), which seems unlikely, as the audio would’ve been transferred to film after only a few days or weeks – or on the film archive (35mm?), which wouldn’t make sense, would it, because I thought the audio track was optical on that format (though I may be thinking of 16mm film I saw as a kid in school)? Though that would sure have potential for long-term storage. OR – could it have happened in a later videotape archive? Anyone? ---
**Author:** ![RealityChuck](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/realitychuck/32/195_2.png) [@RealityChuck](https://boards.straightdope.com/u/RealityChuck)\ **Post date:** [June 8, 2019, 1:57pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/13 "2019-06-08T13:57:00Z")
> [@campp](#): > > I’ve always wondered about that part near the end of Whole Lotta Love (Led Zepplin) if that was tape bleed-through or done on purpose. I tend to think bleed-through. It’s where Plant is slowly wailing “Way down inside…Woman…You need it…Love…” or whatever he sings. It was in the original pressings, so it was clearly deliberate. Not likely a problem with master tapes, since it takes time in storage to develop. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [June 8, 2019, 2:55pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/14 "2019-06-08T14:55:30Z")
> [@banjoDavid](#): > > I think that was caused when Plant sang a scratch vocal track when the whole band played live in the studio, and he overdubbed the new vocal that you hear. The ghost sound is Plant’s voice picked up by mics on the drums and guitar and bass amplifiers. No, that was very much by design. They reversed the audio, added echo and reversed it again. They invented this technique (or so the story goes), called Reverse Echo, which shows up in other places, albeit not as noticeable. > **[Reverse echo](https://en.wikipedia.org/wiki/Reverse_echo)** > > Reverse echo and reverse reverb are sound effects created as the result of recording an echo or reverb effect of an audio recording played backwards. The original recording is then played forwards accompanied by the recording of the echoed or reverberated signal which now precedes the original signal. The process produces a swelling effect preceding and during playback. > Guitarist and producer Jimmy Page claims to have invented the effect, stating that he originally developed the method when reco... ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [June 8, 2019, 4:41pm UTC](https://boards.straightdope.com/t/old-movies-and-tv-shows-audio-bleeding-through/608005/15 "2019-06-08T16:41:31Z")
Nowadays, I’d think that they’d be able to fix this digitally in some at least partially automated fashion. Of course, they’d have to care enough to do it, but I bet that could happen on some darling old shows when they get special rereleases.