Is print through a real issue?

[weegee]

This ebay seller gives it as an excuse for low volume.

https://www.ebay.com/itm/143442576925?ul_noapp=true

Is print through a real issue?

 

[Wilhem]

Print through is a real problem for most tapes, but only if it is noticeable. Reducing the level of the recorded audio reduces the effect of print to the same degree as reducing the audio. The printing is still there, but hard to hear--as hard to hear as the recording is. The coercivity of the pigment, time, and temperature have much greater effects on print than the flux level recorded onto the tape.

 

[KingBubba]

Always leave tape tails out.

 

[dhnash]

Always leave tape tails out.

This is certainly an appropriate suggestion for 1/2-track tapes but not for 1/4-track tapes like the one in the listing included in the original post.

 

[Wilhem]

This is certainly an appropriate suggestion for 1/2-track tapes but not for 1/4-track tapes like the one in the listing included in the original post.

This method of storage is appropriate for all types of analogue tape storage because when the tape is wound for playing, whether the tape is cassette tape or up to 2-inch in width, the print effects begin all over again--and beginning to erase what was printed in the storage position. The effectiveness depends on whether the tape was an A-wind or a B-wind and the recorded speed (wavelengths of the prints) because the flux lines are a bit complicated in their radiation. One day I'll try to dig up or finish the white paper on print-through that might explain this phenomenon in detail.

 

[dhnash]

So which direction of wind represents tails out for a 1/4-track stereo tape where two tracks are recorded in one direction and the other two tracks are recorded in the opposite direction?

 

[Chip Chester]

In theory, whatever way makes you have to rewind before playing "side one", I guess.

But anyway, since print-thru is a non-biased recording, it is somewhat fragile. A lot goes away when being rewound.

 

[jlb2]

Yes, this is correct. Rewinding before playing is standard procedure in the profession. This paper published by 3M, for instance, provides in-depth discussion re. print-through and how to keep it low.

 

[Wilhem]

since print-thru is a non-biased recording, it is somewhat fragile.

Bias has little to do with print effects. The cause is low coercivity of the particles in the pigment due to their chemical and or mechanical stability and, more importantly, their morphology. Particles that are stubby rather than much longer than they are wide are more susceptible to print. Particles that are fractured or cursed with dendrites are also susceptible. It's almost as if these particles are gullible and prone to gossip--when they "hear" something from their neighbors, they believe it and pass it on. When they hear something different and contradictory, they change their belief. Such particles are often called paramagnetic. They are susceptible to changing their magnetic polarity under the influence of magnetic signals around them, whether those signals are above, below, or next to them. Low-print tapes use more refined particles, more filtering, and either less aggressive or different milling or a combination of both to preserve the morphology of the pigment particles so that there are as many with great length-to-width ratios as possible.

 

[Chip Chester]

Wonder if wrapping paper leader within the layers of tape would help or even eliminate print-through... Could be extra reel spooling out/taking up as required, a split-tape-path affair to separate tape from leader material while passing by heads, or even a bonded backing of paper or mylar leader to act as an inter-wrap spacer. Keeping the layers far apart (on a microscopic level) seems like it would diminish print quite a bit.

Flies in the face of both long-playing tapes, and basic practicality, of course. But note early tape was paper-based...

 

[Wilhem]

But note early tape was paper-based...

Increasing the spacing distance between layers would reduce print considerably. Much thicker base film would be easier to manage than adding a second medium between the layers. (Early 3M tape from 1947 was paper-based. BASF tape from 1933 was not. BASF never used paper as a backing.)

 

[Chip Chester]

Tape that pre-dated BASF involvement apparently was, however.

From the Wiki: "Pfleumer's invention used a ferric oxide (Fe2O3) powder coating on a long strip of paper."
(Wiki has been known for occasional inaccuracies, of course...)

The paper inter-layer approach would allow existing high-performing tapes to be used as-is, without waiting for manufacturers to notice, scoff heartily, and reject this odd approach. Preservation of existing masters would be an early application, if deemed safe by archivists. Acid-free paper, or plastic leader with physical properties compatible with existing tape would be my first selection.

 

[Wilhem]

Fritz's idea was clever--but it didn't work.

 

[twiiii]

Any time I was recording professionally I used a Back coated high output 1.5 mil tape for just that reason. You start pegging those meters with a 2 trk or 4 channel 1/2 inch machine running at 15 or 30 ips and print through can become a real issue. Of course with most home type consumer machines other issues pop up first. So don't push things. Keep the needles out of the red. Especially better Nakamichi cassette machines. They can put a lot of level on those tinnie tiny cassettes.