RTR Print-through/bleed-through issue...

[mkuhl2000]

I have always played my own tapes on my Akai GX-4000D until Lab3 and I sent each other some tapes and we both are experiencing the same thing with each other's tapes. In silent sections of the tape during playback (between songs) we hear music in the background in reverse from the other side presumably. Not sure if this is what they call print-through or what...I call it bleed-through which is probably wrong but that is what describes what is happening. Is this an alignment issue between our decks?

 

[Chip Chester]

Yup. Head "height" misalignment, probably. Although you could work it out between yourselves, that would be somewhat pointless. Best to use a real reference/alignment tape for quarter-track stereo.

You might be able to improve things by using a real-time duplicated pre-recorded tape as a guide, but don't think of it as a real alignment with a test tape...

*Height, in this case, refers to the spacing of the recorded tracks above the reference edge of the tape.

Chip

 

[oldvinyldude]

My hunch is that the alignment issue is your deck-not Lab3's.

My reading in many many threads suggests not to attempt to do any alignment yourself, but entrust it to a competent tech. These folks are not always available in your area. Be sure to ask if they use commercially produced alignment tapes and a scope. I would ask the question about how they do the alignment and the tools they use, and look for these details.

Sadly, I have read all sorts of accounts of 'experienced techs' butchering the job, because of inexperience and not having proper alignment tapes, which are expensive.

 

[kfalls]

You could very well be experiencing "bleed-through" on the tape especially if it hs been spored for some time. We noticed this on our professional-quality Masterworks discs at CBS. When music was recorded using high-bias Chromium Dioxide we notice the energy would print through to adjoining layers of tape. It's especially noticeable in the blank tape between tracks. I don't think there is a way to get rid of it, but certain a head alignment won't fix it.

 

[mkuhl2000]

I think I will try to take one of Lab3's tapes and align against it and then adjust the record head to match and send him another tape and see what happens. I moved the record head a little and the high end came through better than before. Gonna tinker and see what results I can get

 

[Chip Chester]

Wiki has a little thing about print through that seems mostly right. It is an unstable thing, so rewind and 'rest' prior to playback can improve things a little. For critical masters, I've often wondered if interweaving paper or plastic leader tape between each program tape layer would help in the long run. The tape machine would have to look more like a flatbed film editor, though...

But for the apparent track alignment thing here, can you get some test tones recorded by Lab3? That'll help to A: set the PB azimuth correctly, using a scope and Lissajous figures. Then adjust PB height for maximum signal. Then re-verify azimuth. Then, B: Adjust record head so that PB head's output is the same as the Lab3 tape. This is all "walk it in, count turns of adjust screw, split the difference between dropoffs" stuff. If you can monitor PB while recording, this is easier. If you can monitor the record head as a playback head, then set it using the Lab3 tape, too. (Don't know if that's possible on the Akai.)

If you have a phase reversal switch available to you (via a mixer, maybe) then it's possible to get close without a scope. It's just easier with one.

Chip

 

[oldvinyldude]

Wiki has a little thing about print through that seems mostly right. It is an unstable thing, so rewind and 'rest' prior to playback can improve things a little.

I was under the impression that print through would show up as pre or post echo of the same track, and would be heard as 'forward' not backwards, as the OP had heard.

My impression is from a ton of reading though, so I may well not understand these things. I will defer to others.

If the signal heard is from adjacent tracks, I would gather the alignment (height) would have to be off considerably, as there is supposed to be dead space between tracks (guard band), and it would take a considerable misalignment to cross that band into an adjacent track.

I did buy a bunch of old standard (not even LN/HO tape) reels of tape, and had had been recorded on a machine in the 60's. I would hear the 'other side' as a muted backwards signal, when I attempted to listen to these. Other home recorded tapes (needle drops, etc) that I would listen to on the same deck, did not have this effect. My presumption was mis alignment of the recording deck.

 

[mkuhl2000]

If the signal heard is from adjacent tracks, I would gather the alignment (height) would have to be off considerably, as there is supposed to be dead space between tracks (guard band), and it would take a considerable misalignment to cross that band into an adjacent track.

Well I recorded some of the sound between tracks on my computer and then reversed it and sure enough it is the song on the other side of the tape. I've tinkered and gotten better sound...but still can't kill the signal from the other side. Looks like I need to find somebody in the Dallas area that can do an alignment on it as I am really just winging it here with a screwdriver. :sigh:

 

[audiojones]

Crosstalk

I was under the impression that print through would show up as pre or post echo of the same track, and would be heard as 'forward' not backwards, as the OP had heard.

You are correct, print through or "bleed through" is usually an echo effect in the forward direction caused by rewinding and storing a hot recording instead of leaving it "tails out" on the take up reel. Probably the most famous example of this is is Led Zeppelin's "Whole Lotta Love" near the end when Robert Plant's vocals are echoed with the before and after vocals (allegedly done by accidentally storing the master tape incorrectly).

What the OP is describing is called CROSSTALK. It can be caused by heads that have trouble focusing on the magnetic field that they are supposed to be reproducing, either because of misalignment, wear or poor playback head design. It can also be caused by a recording that is too hot, misaligned or worn record head or poor record head design.

When you play a 1/4 track stereo reel of tape you are playing tracks 1 and 3 (left and right) in the forward direction. You will always have the tracks for the opposite side (tracks 2 and 4 ) riding alongside the tracks that you are listening to, and naturally they will be going in the opposite direction. A properly recorded tape on a properly aligned machine with heads that are in good shape will have only a minimal amount of track to track crosstalk (hearing some of tracks 2 and 4 while listening to tracks 1 and 3 in this case). A machine with worn, misaligned or poorly designed heads will have trouble focusing on the magnetic field that it is supposed to reproduce and you get crosstalk. Alignment may not cure it, there are some heads that are more susceptible to this than others.

Obviously it's not an issue with full two track recordings (where the tape is split 50/50 left and right one direction) or full track mono recordings. 1/2 track mono rarely has an issue with this either.