Correcting tape print through.

farss wrote on 6/6/2005, 5:10 AM
Bit of a blast from the past I know. Got some R2R tapes to deal with and amongst other problems they suffer from print through, not terribly bad but noticable. I'm thinking theoretically it might just be possible to fix this, given that it just the same audio from a later/earlier part of the tape. But then I realise there's two potential problems.
Firstly being analogue the speed will not be 100% constant so the offset I'm going to need will keep shifting and also as the diameter of the tape pack gets smaller it'll also change.
So maybe it's going to be impossible to achieve, just wondering if anyone's ever had any success?
Bob.

Comments

adowrx wrote on 6/6/2005, 5:15 AM
Were the reels stored tails out?


farss wrote on 6/6/2005, 6:12 AM
Nope!
I just readup on why they should have been though. This doesn't stop print through, just makes it less objectionable as it's post rather than pre recording.
Bob.
tazio wrote on 6/7/2005, 4:41 AM
Back on the cutting edge, Bob? I was going to suggest some sort of out of phase delay thingie, kind of like your method for reducing reverb, but you're right, the tape speed variations would render this useless. I'll talk with my boss tomorrow - he's from the era that would know about that sort of thing...

...hang on, I'm from that era too!?! I can't remember anything about how to remove print-through, but I will ask David.

I recall wondering what that little bit of ghostly pre-echo was all those years ago at the beginning of Led Zep 4. Took years to find out about the wonders of print-through. Apparently the tape was saturated to the point of unavoidable print-through! Kind of makes me think all that head-banging was worthwhile

Phil
farss wrote on 6/7/2005, 5:53 AM
And only a few days ago the sound guy on a job I was working on was trying to tell me how much better the old mag tape was to record with, he still runs two 1" decks in his studio.
It is kind of relaxing watching those reels go round and round and round. You know there's just no way to make it happen faster so you just relax and veg out. Well until you see a splice coming along and then your heart misses a beat, will that 30 year old glue still hold it together.
Bob.
tazio wrote on 6/7/2005, 9:32 PM
Well, the only word from the boss is that sometimes it can be reduced by a tape spool-through - but by the sounds of the 30 year old splices you may be a bit wary of doing that.

Well enjoy the meditative effects of watching the reels go round - maybe someone could write a plug-in that puts some spining reels at the bottom of the screen - make us analog-digital cross-overs feel a bit more comfy
farss wrote on 6/8/2005, 6:59 AM
His advice agrees with the paper I read from Ampex, as the layers of tape part the separating fields partially erase the print through by as much as 6dB.
Thanks for asking, but as Google turned up nothing and it was a pretty common problem I figured if anyone had found a fix it'd be out there.
Bob.