Sometime within the next few months, I intend to begin a big project;
archiving an entire collection of old family tape recordings. These are all
on 7" reels, most are mono but some are in stereo. The main reason for this
project is that many of the tapes are plastic-based, and at over 40 years
old they are starting to deteriorate. I first noticed this some 14 years
ago, when one tape snapped during rewind and had to be spliced.
Most of the recordings are of high quality, but a few are marginal at
best. Some were recorded poorly indeed and at least one is barely audible
even at full volume.
My question is, what software is best for digitally restoring noisy old
recordings? I've been looking at Dart XP Pro (www.dartpro.com) and this
appears to be a very good program but I'd like some opinions. I don't want
to spend a fortune, nor do I want something that will run poorly on my
1.1Ghz machine.
Thanks for any opinions.

On 10/1/05 5:56 PM, in article
, "Chris F."
wrote:

My question is, what software is best for digitally restoring noisy old
recordings? .... I don't want to spend a fortune, nor do I want something that
will run poorly on my 1.1Ghz machine.

Well, pretty much the best is the Cedar suite of tools, although
Algorhythmix has got a good reputation as well.

Waves suite of Restoration tools works pretty well if not pushed too hard.
Others have liked the Sound Soap tool from Bias.

Good luck.

Allen
--
Allen Corneau
Mastering Engineer
Essential Sound Mastering
www.esmastering.com

Chris F. wrote:
Sometime within the next few months, I intend to begin a big project;
archiving an entire collection of old family tape recordings. These are all
on 7" reels, most are mono but some are in stereo. The main reason for this
project is that many of the tapes are plastic-based, and at over 40 years
old they are starting to deteriorate. I first noticed this some 14 years
ago, when one tape snapped during rewind and had to be spliced.
Most of the recordings are of high quality, but a few are marginal at
best. Some were recorded poorly indeed and at least one is barely audible
even at full volume.
My question is, what software is best for digitally restoring noisy old
recordings? I've been looking at Dart XP Pro (www.dartpro.com) and this
appears to be a very good program but I'd like some opinions. I don't want
to spend a fortune, nor do I want something that will run poorly on my
1.1Ghz machine.

Spend your money on transcription. Get a scope, get the right head
configuration for your deck. Get the best possible copy off the tape
that you can get.

You may find, for example, that the tape that is barely audible is a
quarter-track tape, and that when played with the right heads, it might
be very audible. Likewise, getting the azimuth adjusted right can be
the difference between a good transcription and an unworkable one, and
the azimuth issues get worse as the tape speed drops.

Noise reduction for tape basically means broadband noise removal and
little else. I can strongly recommend the new CEDAR broadband box,
and you don't need to buy it, you can send stuff off to a post house
that has one to do the work. Don't expect a miracle, but you can do
a good job of bringing audible hiss down.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

All tape recorders I've used to play back these tapes, had the heads
aligned while playing back high quality pre-recorded tapes. Most of the old
recordings were made on a single Philips machine (EL3534) and the heads were
never touched on it.
I'll try to describe two such recordings a bit better. One is simply a
poor second-generation copy; a copy made by placing a mic next to the
speaker during playback. Basically a lot of hiss and rumble. The other
recording has a more interesting story:
I was browsing one of the tapes a few months ago and came across a section
of tape (one channel only) that had obviously been erased with silence,
however there was a faint high-frequency noise present which I can't
explain. But then I noticed some voices coming through; a selection labeled
on the box had been crossed out and supposedly erased, but amazingly I could
still hear it faintly on the opposite track, with the volume at max. I think
this may explain it; the original recording was made on a different machine;
I believe that when it was erased on the newer machine, a slight difference
in head alignment kept the old recording from being totally erased. Had the
opposite channel been used also, obviously, the original recording would
have been completely obscured. I was quite elated to discover this recording
almost 40 years after it had supposedly been erased! Sorry for the poor
description but I think you can still get the picture.
So nobody has used the DART programs??

Chris F. wrote:

So nobody has used the DART programs??

Not for tape noise reduction, no. I seem to recall it was pretty good at
click and pop removal, though, and reasonably okay on noise removal for
78s.

IIRC the noise reduction is based on the pattern-matching idea, like the DNR
in Audacity and Goldwave, but more tweakable.
You take a sample containing just the noise, and apply it to the rest of the
recording. It can cause MP3-like artifacts to occur.

--
JP Morris - aka DOUG the Eagle (Dragon) -=UDIC=-
Anti-walkthroughs for Deus Ex, Thief and Ultima http://www.it-he.org
Reign of the Just - An Ultima clone http://rotj.it-he.org
The DMFA radio series project http://dmfa.it-he.org
d+++ e+ N+ T++ Om U1234!56!7'!S'!8!9!KAW u++ uC+++ uF+++ uG---- uLB----
uA--- nC+ nR---- nH+++ nP++ nI nPT nS nT wM- wC- y a(YEAR - 1976)

. Record mono recordings
stereo, then you can sum the both tracks up after you've inverted the
right track.

I'm not familiar with that procedure, what exactly do you mean?

Chris F. wrote:
All tape recorders I've used to play back these tapes, had the heads
aligned while playing back high quality pre-recorded tapes. Most of the old
recordings were made on a single Philips machine (EL3534) and the heads were
never touched on it.

That's why it's important to align the heads on the playback machine to
match the error of the original heads on the record machine. Aligning
the heads against a known-good tape is useless when you know you are going
to be playing back a tape with some error.

You'll probably only need to set it once.

I'll try to describe two such recordings a bit better. One is simply a
poor second-generation copy; a copy made by placing a mic next to the
speaker during playback. Basically a lot of hiss and rumble.

You can equalize things, but you can't do anything about the distortion
from the playback speaker, which is the real issue for these recordings.
Or the acoustical effects. Sometimes you can notch out resonances with
a parametric which can help a lot.

The rumble is usually correctable with a low cut. For the hiss, you will
need something like CEDAR for broadband noise reduction. You still want
to get the best possible playback, though, so you have as much to work
with as possible.

The other
recording has a more interesting story:
I was browsing one of the tapes a few months ago and came across a section
of tape (one channel only) that had obviously been erased with silence,
however there was a faint high-frequency noise present which I can't
explain. But then I noticed some voices coming through; a selection labeled
on the box had been crossed out and supposedly erased, but amazingly I could
still hear it faintly on the opposite track, with the volume at max. I think
this may explain it; the original recording was made on a different machine;
I believe that when it was erased on the newer machine, a slight difference
in head alignment kept the old recording from being totally erased. Had the
opposite channel been used also, obviously, the original recording would
have been completely obscured. I was quite elated to discover this recording
almost 40 years after it had supposedly been erased! Sorry for the poor
description but I think you can still get the picture.

Right, for this you need a narrowtrack machine and you need to ride the
head up and down in order to get the best sound quality off of a narrow
section of tape. Spray with Magna-See first so you can see where you
are. You want to play back _only_ the unerased part of the tape... the
narrower the playback track, the better S/N you'll get.

So nobody has used the DART programs??

I played with them, and they kind of work, but they aren't anything to
write home about. And the broadband noise reduction is probably the least
effective thing in the kit.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On Sun, 02 Oct 2005 22:33:56 GMT, "Chris F."
wrote:

. Record mono recordings
stereo, then you can sum the both tracks up after you've inverted the
right track.

I'm not familiar with that procedure, what exactly do you mean?

-- If you've got a mono recording recorded in the PC from a stereo
tape recorder (unless you've got a full-track mono played back with a
full-track playback head), you have two almost identical tracks. The
difference can be seen at the right track in, say, Sound Forge if you
apply a mid/side matrix setting. This difference should be cancelled
and in the major part it will be by such an inverting and summing up.
It works good with mono records played back by a stereo cartridge,
too.

Edi Zubovic, Crikvenica, Croatia

"Chris F." wrote in
message


Sometime within the next few months, I intend to begin a
big project; archiving an entire collection of old family
tape recordings. These are all on 7" reels, most are mono
but some are in stereo. The main reason for this project
is that many of the tapes are plastic-based, and at over
40 years old they are starting to deteriorate. I first
noticed this some 14 years ago, when one tape snapped
during rewind and had to be spliced. Most of the
recordings are of high quality, but a few are marginal at
best. Some were recorded poorly indeed and at least one
is barely audible even at full volume. My question is,
what software is best for digitally restoring noisy old
recordings? I've been looking at Dart XP Pro
(www.dartpro.com) and this appears to be a very good
program but I'd like some opinions. I don't want to spend
a fortune, nor do I want something that will run poorly
on my
1.1Ghz machine.
Thanks for any opinions.

Adobe Audition has a ton of tools for this purpose and a
long list of enthusiastic users.

I use the Waves Restoration for work and it works well.
However, it had trouble running on our 2GHz, 1G ram machine sometimes.