Restoring many-generation tapes

[radiorog]

I have some old analog tapes that are so many generations old that it's amazing there's any frequency left in them at all. Any suggestions for some EQ, comp, etc. settings that can restore them to reasonable fidelity? Or maybe some magic plugin that might do the job?

TIA

Roger

[Naturally Digital]

Hi Roger,

There are no easy answers here. Take your time with it and peel away the layers one at a time. Try to 'uncover' the information on the tapes. If you feel you're getting nowhere quick, start over again.

Ideally, you have blank sections of the tape that you can sample. Use that for 'noiseprint' type noise reduction. Once you've run a pass (or more) with that, then start with EQ or dynamic type NR.

Do your best to 'preserve' the information. In other words, make subtle changes.

It's been suggested that adding a touch of reverb after all the NR can enhance the intelligability.

Perhaps Angie will chime in here. This is her specialty.

What kind of material is it?

Dave.

[radiorog]

Thanks, Dave.

They're classic radio shows from the 1940s, dubbed many years ago from the original 16" transcriptions. They may not have been properly equalized in the first place, when dubbed to tape. But the copies I have are many generations away from the original tapes.

I've tried different EQ settings, on the assumption that as tapes are copied and recopied, the low and high ends are the first to go. This seems to help a little. The reverb idea is intriguing.

I'm eager to hear what Angie might suggest.

Roger

[Naturally Digital]

Roger,

What's the goal with it. Does it need to be 'enjoyable' to listen to or are you trying to recover scripts or what?

What plug-ins or tools do you have at your disposal?

The list of things to look at goes something like this:

- Virtos Audio NR
- Sony (formerly sound forge) NR
- Waves NR
- Arboretum Restorator
- Bias Soundsoap
- DC Live Forensics
- Algorithmix
- Sound Cleaner or Clearvoice from speechpro.com

plus the obvious ones that are built in to certain applications...
Adobe Audition (formerly Cooledit) and Samplitude have some good tools.

Did I miss any? Thanks to all those who offered suggestions in my time of need! ;)

Dave.

[Angie]

Roger,

I'm not sure I can add much to what Dave has suggested already. I won't say it's hopeless, but don't expect perfection.

If its many generations removed, I would think that there will have been lots of noise introduced as well as the expected frequency loss.

There are no quick fixes. It will take time and a lot of trial and error. I would suggest concentrating on noise reduction first. Use moderate or low settings and many many passes instead of trying to remove everything in one pass. The programs I use regularly for this are DC-Art (DC5 now) and the Virtos Denoiser. DC5 is stand-alone where the Virtos is a plug-in.
Also be aware that the upper frequencies may not have been on the original recording in the first place. And boosting those frequencies may not add anything but more hiss. Just cutting some low mids might bring things out a bit.

Now, since these are classic radio programs from the 1940's, the chances that good copies are already available commercially is pretty high. Sometimes purchasing these is a better route to take. When Radio Was has a fairly good catalog available on line.

Hope some of this helps,
Angie