You are here

Transferring old tapes

For everything after the recording stage: hardware/software and how you use it.

Transferring old tapes

Postby twotoedsloth » Wed Feb 01, 2012 6:30 pm

Hello,

I've been given a stack of 1/4 inch 3 3/4 ips tapes to transfer to CD. Is there a reason why I can't transfer these at 7.5 ips and then transpose down an octave before burning the discs?

Thanks all.
twotoedsloth
Frequent Poster
Posts: 701
Joined: Sat Jan 26, 2008 12:00 am

Re: Transferring old tapes

Postby Nebulae » Wed Feb 01, 2012 9:02 pm

Artifacts from the transpose?
User avatar
Nebulae
Regular
Posts: 80
Joined: Sat Sep 18, 2004 11:00 pm

Re: Transferring old tapes

Postby Exalted Wombat » Wed Feb 01, 2012 9:09 pm

twotoedsloth wrote:Hello,

I've been given a stack of 1/4 inch 3 3/4 ips tapes to transfer to CD. Is there a reason why I can't transfer these at 7.5 ips and then transpose down an octave before burning the discs?

The playback eq curve on the tape deck will be wrong. You'll be asking the signal path to deal with frequencies twice what it's designed for.

But then, cassette playback with Dolby switched off SHOULDN'T be an improvement, but sometimes is! Try it and see. Results may be acceptable.
Exalted Wombat
Jedi Poster
Posts: 5643
Joined: Sat Feb 06, 2010 12:00 am
Location: London UK

You don't have to write songs. The world doesn't want you to write songs. It would probably prefer it if you didn't. So write songs if you want to. Otherwise, dont. Go fishing instead.


Re: Transferring old tapes

Postby ken long » Wed Feb 01, 2012 9:59 pm

apart from EQ already mentioned - there might be other considerations:

1. If this is a paid gig transferring at 7.5 will obviously mean the job is finished double quick. Good if you factored per tape. Not so good if you based your valuation on time.

2. what are the tapes holding? I'd be loathe to playback unique recordings, particularly music performances, at double the recorded speed. 3.75 was never "excellent", but why make it worse?

I'd hire out another tape machine and do a parallel ingest. Use error analysis software post transfer to point out any clicks or dropouts.

If you really must use 7.5, I would advise a high sample rate. 88.2 - 192 if you can, before you pitch it down digitally.
User avatar
ken long
Frequent Poster
Posts: 3155
Joined: Mon Jan 21, 2008 12:00 am
Location: The Orient, East London

I'm All Ears.


Re: Transferring old tapes

Postby twotoedsloth » Thu Feb 02, 2012 12:15 am

Thanks so much for your responses. It's not really a paid job, I might get a coffee card out it if I'm friendly and lucky. They are live concert recordings of a classical pianist (former university professor where I work) made between 1982 and 1991. There are 22 tapes to be transferred.

The main problem (aside from time and lack of interest) is that my predecessor got rid of most of the old tape decks, so now the only quarter inch deck we have is a Revox that will only do 15 ips or 7.5 ips. I guess I will have to track down a machine that will do 3.75 ips.

How serious do you think the EQ curve issue is? Obviously, recording at 88.2, it is trivial to reduce it to 44.1 since there will be no altered samples.

The only bright side to this project is that they are live concert recordings, so I don't need to go through the tapes to find the splices and retape them.
twotoedsloth
Frequent Poster
Posts: 701
Joined: Sat Jan 26, 2008 12:00 am

Re: Transferring old tapes

Postby ken long » Thu Feb 02, 2012 1:08 am

I'd be concerned with getting correct azimuth before worrying about the EQ to be honest. But yeah, if you can get it right, it's worth doing right. Shouldn't be hard to get hold of a slower machine but without a budget, you may have to just cut some corners. Is it a PR99 Mk3 by any chance?
User avatar
ken long
Frequent Poster
Posts: 3155
Joined: Mon Jan 21, 2008 12:00 am
Location: The Orient, East London

I'm All Ears.


Re: Transferring old tapes

Postby James Perrett » Thu Feb 02, 2012 9:56 am

Unless your deck is optimised for higher than audio frequencies (as some duplication decks are) you will find that transferring at 7.5ips will cause the high frequencies to be lost. A typical deck (say a Revox A77) may handle up to 16kHz at 3.75ips and 20kHz at 7.5ips. If you play the tape at 7.5ips and then slow the recording down digitally you'll end up with the frequency response tailing off at 10kHz.

As Ken says, azimuth adjustment is also more critical at slow speeds.

So it isn't a great idea to do what you propose although you might get away with it for non-critical tapes.

James.
James Perrett
Moderator
Posts: 5772
Joined: Sun Sep 09, 2001 11:00 pm
Location: The wilds of Hampshire

JRP Music - Audio Mastering and Restoration.
http://www.jrpmusic.co.uk


Re: Transferring old tapes

Postby Folderol » Thu Feb 02, 2012 6:14 pm

I really don't think there is any alternative to running them at the correct speed for reasons as above. Also, if you have the time do do the job thoroughly adjust the azimuth individually for each tape - on a listening test a little way into the tape set for maximum treble content. If you can get a professional machine with three point head adjustment, also consider adjusting head height for minimum cross-talk.
User avatar
Folderol
Jedi Poster
Posts: 4556
Joined: Sat Nov 15, 2008 12:00 am
Location: Rochester, UK

Save paradise, Pull up a parking lot!


Re: Transferring old tapes

Postby twotoedsloth » Fri Feb 03, 2012 2:12 am

It's a Revox G36. Strangely a couple of websites I've browsed say it offers a 3.75 tape speed... I'm quite sure this one doesn't.

This seems like a job more suited to an archivist rather than a recording tech.

Thanks for your suggestions.
twotoedsloth
Frequent Poster
Posts: 701
Joined: Sat Jan 26, 2008 12:00 am

Re: Transferring old tapes

Postby ken long » Fri Feb 03, 2012 10:03 am

yes, apparently there's a switch (No.3) for 7.5 / 3.75. Maybe not on your model?

Image
User avatar
ken long
Frequent Poster
Posts: 3155
Joined: Mon Jan 21, 2008 12:00 am
Location: The Orient, East London

I'm All Ears.


Re: Transferring old tapes

Postby James Perrett » Fri Feb 03, 2012 10:12 am

I've never heard of a high speed G36 although high speed A77's and B77's were fairly common. Has it been modified perhaps? Could you remove the modifications to make it work at 3.75ips?

James.
James Perrett
Moderator
Posts: 5772
Joined: Sun Sep 09, 2001 11:00 pm
Location: The wilds of Hampshire

JRP Music - Audio Mastering and Restoration.
http://www.jrpmusic.co.uk


Re: Transferring old tapes

Postby Hugh Robjohns » Fri Feb 03, 2012 10:58 am

It might be that a collar or sleeve has ben added to the capstan to double its diameter, or that the motor has been replaced for one with a double-diameter shaft or spindle. It wasn't an uncommon modification...

An alternative suggestion is to borrow or acquire an old Akai DS4000 or similar -- in fact any reel-reel machine intended for domestic use. They would be more likely to have the 3-3/4 ips setting. (The Akai changed speeds by unscrewing a cap on the capstan and adding or removing a sleeve!).

Or... the Studer A807 has three speeds including 3-3/4 ips if you can find somewhere or someone with one of those...

Hugh
User avatar
Hugh Robjohns
Moderator
Posts: 16790
Joined: Thu Jul 24, 2003 11:00 pm
Location: Worcestershire, UK

Technical Editor, Sound On Sound


Re: Transferring old tapes

Postby Exalted Wombat » Fri Feb 03, 2012 11:42 am

twotoedsloth wrote:Thanks so much for your responses. It's not really a paid job, I might get a coffee card out it if I'm friendly and lucky. They are live concert recordings of a classical pianist (former university professor where I work) made between 1982 and 1991. There are 22 tapes to be transferred.

I think you have enough information now to go back to whoever commissioned the work, explain what is possible with the equipment you have and point out that results may not be perfect.

They may be assuming it's a trivial job.
Exalted Wombat
Jedi Poster
Posts: 5643
Joined: Sat Feb 06, 2010 12:00 am
Location: London UK

You don't have to write songs. The world doesn't want you to write songs. It would probably prefer it if you didn't. So write songs if you want to. Otherwise, dont. Go fishing instead.


Re: Transferring old tapes

Postby twotoedsloth » Sat Feb 04, 2012 2:59 pm

Well, it was worth a try. This morning I tried to transfer a few minutes of one of the tapes at 7.5 ips 88.2khz resolution, and it sounded horrible, before and after transposing down 1 octave. Thin and scratchy, yet muted at the same time, in short, awful.

So now I get to hunt for a tape machine that will work at 3.75 ips.

Thanks everyone for your helpful suggestions, advice and observations.
twotoedsloth
Frequent Poster
Posts: 701
Joined: Sat Jan 26, 2008 12:00 am

Re: Transferring old tapes

Postby twotoedsloth » Mon Feb 13, 2012 10:19 pm

Does anyone know anything about Uher? I'm not familiar with them. I've been offered a 4 track stereo (I assume they mean 2 tracks one way, and two tracks with the tape reversed) quarter inch recorder/player that will do 3.75 ips for $20. Obviously, for the money I can't lose, but I need to go and get it, which will take a couple of hours.

Your advice, please, kind folks.
twotoedsloth
Frequent Poster
Posts: 701
Joined: Sat Jan 26, 2008 12:00 am

Re: Transferring old tapes

Postby Hugh Robjohns » Mon Feb 13, 2012 10:27 pm

Uhers were used widely as broadcast (radio) location recorders. Loads of stuff on the net about them. I think all models we restricted to 5 inch spools... But maybe there were larger machines.

Hugh
User avatar
Hugh Robjohns
Moderator
Posts: 16790
Joined: Thu Jul 24, 2003 11:00 pm
Location: Worcestershire, UK

Technical Editor, Sound On Sound


Re: Transferring old tapes

Postby twotoedsloth » Mon Feb 13, 2012 11:13 pm

Thanks for your response. Someone on this thread earlier recommended a consumer model tape deck, I believe this Uher is a professional model. Also, it may or may not only work with 5 inch reels. I understand the seller in that for $20 I shouldn't expect too much from him, and he doesn't even have the manual anymore.

Do you think it's worth the 2 hours or so commute to pick it up? And is it even possible to carry one of these recorders on public transit, or will I need to hire a cab (which will certainly cost more than the unit)?

Thanks,

Peter
twotoedsloth
Frequent Poster
Posts: 701
Joined: Sat Jan 26, 2008 12:00 am

Re: Transferring old tapes

Postby Mike Stranks » Tue Feb 14, 2012 8:11 am

As ever, you'll find Google is your friend...

A very quick search found this:

Uher Tape-recorder

which shows that they did make machines other than the portables. (I thought I recalled that they had done, but couldn't be sure. Very rare beasts in the UK!)

The page I've referenced gives all the info including the weight.

Suggest you need to talk to the seller to find out the model number and whether it's in full working order.
User avatar
Mike Stranks
Jedi Poster
Posts: 4227
Joined: Fri Jan 03, 2003 12:00 am
Location: Cirencester, UK

 


Re: Transferring old tapes

Postby James Perrett » Tue Feb 14, 2012 9:55 am

As others have said, you need to get the model number from the seller. If he's calling it a professional it is likely that it is one of the smaller portable models as I don't think any of the larger models found their way into professional use. These can be easily carried on public transport. Just be aware of the 5 inch reel limit on the smaller recorders.

Personally I would treat one of these machines as an interesting curiosity - while it may make some sound, it may well need some work to get it working properly as rubber belts and idlers could have deteriorated. Be prepared to spend a little time bringing it up to full spec.

James.
James Perrett
Moderator
Posts: 5772
Joined: Sun Sep 09, 2001 11:00 pm
Location: The wilds of Hampshire

JRP Music - Audio Mastering and Restoration.
http://www.jrpmusic.co.uk


Re: Transferring old tapes

Postby Folderol » Tue Feb 14, 2012 6:30 pm

Hmmm. Mentioning Uher reminds me I probably have access to a Report 4400 which I think is in reasonable condition.

Where in the country are you? If it's not a million miles away I might be able to arrange a loan.
User avatar
Folderol
Jedi Poster
Posts: 4556
Joined: Sat Nov 15, 2008 12:00 am
Location: Rochester, UK

Save paradise, Pull up a parking lot!


Re: Transferring old tapes

Postby Exalted Wombat » Tue Feb 14, 2012 8:17 pm

Folderol wrote:Hmmm. Mentioning Uher reminds me I probably have access to a Report 4400 which I think is in reasonable condition.

Where in the country are you? If it's not a million miles away I might be able to arrange a loan.

Yes, where are you? There's an Akai 4000D in a cupboard here (East London.Essex). Can't guarantee the rubber bits are still usable though.
Exalted Wombat
Jedi Poster
Posts: 5643
Joined: Sat Feb 06, 2010 12:00 am
Location: London UK

You don't have to write songs. The world doesn't want you to write songs. It would probably prefer it if you didn't. So write songs if you want to. Otherwise, dont. Go fishing instead.


Re: Transferring old tapes

Postby James Perrett » Wed Feb 15, 2012 9:50 am

Folderol wrote:
Where in the country are you? If it's not a million miles away I might be able to arrange a loan.

From looking at the email in his profile, I suspect that Canada is a little too far for you.

James.
James Perrett
Moderator
Posts: 5772
Joined: Sun Sep 09, 2001 11:00 pm
Location: The wilds of Hampshire

JRP Music - Audio Mastering and Restoration.
http://www.jrpmusic.co.uk


Re: Transferring old tapes

Postby ken long » Wed Feb 15, 2012 4:28 pm

twotoedsloth wrote:Well, it was worth a try. This morning I tried to transfer a few minutes of one of the tapes at 7.5 ips 88.2khz resolution, and it sounded horrible, before and after transposing down 1 octave. Thin and scratchy, yet muted at the same time, in short, awful.

Leaving aside all other factors, have you checked the heads are still useable? And if so, have you given them a thorough clean? A Q-tip imbibed in Iso=propyl alcohol should do the trick.
User avatar
ken long
Frequent Poster
Posts: 3155
Joined: Mon Jan 21, 2008 12:00 am
Location: The Orient, East London

I'm All Ears.


Re: Transferring old tapes

Postby Folderol » Wed Feb 15, 2012 4:45 pm

James Perrett wrote:
Folderol wrote:
Where in the country are you? If it's not a million miles away I might be able to arrange a loan.

From looking at the email in his profile, I suspect that Canada is a little too far for you.

James.
Ah! Yes, that would be a bit of a problem
User avatar
Folderol
Jedi Poster
Posts: 4556
Joined: Sat Nov 15, 2008 12:00 am
Location: Rochester, UK

Save paradise, Pull up a parking lot!


Re: Transferring old tapes

Postby twotoedsloth » Thu Feb 16, 2012 5:29 pm

Thank you for your kind offers to lend me an open reel tape deck, but as you've already noticed, I'm a bit far away here in "the colonies".

So, I went to pick up the Uher recorder... and found out it is actually a Sony "stereo center 230". Not sure how the seller thought it was a Uher. Again, for $20 I guess I can't expect much.

Anyways, it does do 3.75 ips, so I should be good to go.

If I could bother you with one more question, is there anything I should do with the tapes? A colleague suggested I play them back in reverse, and then flip them before burning the CD. He tells me it will preserve the transients. Is there anything to this? I remember being told years ago to store tapes tail out, but I don't remember why.

A final note... what you guys used to call portable is insane. This "portable" recorder must weigh at least 25 pounds.

Thanks,

Peter
twotoedsloth
Frequent Poster
Posts: 701
Joined: Sat Jan 26, 2008 12:00 am

Re: Transferring old tapes

Postby Hugh Robjohns » Thu Feb 16, 2012 5:39 pm

twotoedsloth wrote:Anyways, it does do 3.75 ips, so I should be good to go.

I'd suggest giving the heads and any guides a really good clean with the isopropyl alcohol first, and check the condition of the pinch roller. hey often dry out and become brittle.. but they can also become sticky... neither of which is good for the tapes!

Also, check the transport works properly and safely with a non-critical tape. The last thing you want to do is stretch or shred an irreplaceable tape on the first play!

If I could bother you with one more question, is there anything I should do with the tapes? A colleague suggested I play them back in reverse, and then flip them before burning the CD. He tells me it will preserve the transients. Is there anything to this? I remember being told years ago to store tapes tail out, but I don't remember why.

Storing tapes tail out is about managing the inherent print through cross-magnetism by ensuring if it is to be audible it will be as easily acceptable post echoes rather than more obvious pre-echoes.

I don't think there is likely to be any practical benefit from playing the tapes backwards in order to preserve transients, and I think the 'science' behind that idea is pretty dubious.

A final note... what you guys used to call portable is insane. This "portable" recorder must weigh at least 25 pounds.

Ah yes, I don't miss the days of lugging two 'portable' Studer tape machines and a mixing console full of transformers around between sessions!

hugh
User avatar
Hugh Robjohns
Moderator
Posts: 16790
Joined: Thu Jul 24, 2003 11:00 pm
Location: Worcestershire, UK

Technical Editor, Sound On Sound


Re: Transferring old tapes

Postby ken long » Thu Feb 16, 2012 5:52 pm

I would library wind the tapes through and back. This can reduce the printhrough slightly but also packs the tape up nicely. Keep an eye out for any shed and makes sure the tape is properly guided. And clean clean clean those heads. It makes a world of difference. Let us know how you get on!
User avatar
ken long
Frequent Poster
Posts: 3155
Joined: Mon Jan 21, 2008 12:00 am
Location: The Orient, East London

I'm All Ears.


Re: Transferring old tapes

Postby twotoedsloth » Tue Feb 21, 2012 7:17 pm

Thanks everyone,

So far everything is working great. A quick question: if there was oxide shedding (which, so far, there is not) what would one do about that? Also, by library wind do you mean running the tape from one reel to the other without engaging the read/write head? Sort of like what we used to do with DAT tapes before using them the first time?

Sorry, I'm really in over my head with this analog tape.
twotoedsloth
Frequent Poster
Posts: 701
Joined: Sat Jan 26, 2008 12:00 am

Re: Transferring old tapes

Postby ken long » Tue Feb 21, 2012 9:07 pm

if it's shedding, you'll see it on the guides and heads. Just slow wind to the end and back . You can get a better pack like that before you start and any splices on the tape that might have dried out can be sorted out before you start. It will also give you an idea of the state of the tape. If it starts to shed and really gums up the machine, you could try baking. It really depends on the formulation brand and date of production as well as batches within those runs. I once had some new tape shed out of the box but was fine to use and has lasted.

This website has some good info.
User avatar
ken long
Frequent Poster
Posts: 3155
Joined: Mon Jan 21, 2008 12:00 am
Location: The Orient, East London

I'm All Ears.


Re: Transferring old tapes

Postby James Perrett » Wed Feb 22, 2012 9:38 am

ken long wrote:Just slow wind to the end and back .

Not sure how many domestic machines have a slow wind mode though.

My Philips machine has a slider labelled wind speed - and people who see it often ask if I can control the weather with it

James.
James Perrett
Moderator
Posts: 5772
Joined: Sun Sep 09, 2001 11:00 pm
Location: The wilds of Hampshire

JRP Music - Audio Mastering and Restoration.
http://www.jrpmusic.co.uk


Next

Who is online

Users browsing this forum: Jeraldo and 2 guests