Repairing damaged audio from cassette

[Sam]

Hello. I regularly check audio books out of the library and have come
across a handful that seem to have similar damage. In order to listen
to the recordings, I am hoping I might be able to record the audio to
my PC and fix it up.

The damage is two-part:

1. The audio continuously fades in and out (say from 100% down to 20%
volume - not all the way to 0% volume), on something like a 1 or 2
second period (the period may change over the course of the tape - I
believe it is related to the amount of tape on the spool at any given
time). This is the more serious problem.

2. There are 1 or more forward & backward echos continuously going on.
For example, imagine listening to 5 tape players simultaneously
playing copies of the same tape.
The 1st player has volume 20% and starts at 0:00
The 2nd player has volume 60% and starts at 0:01
The 3rd player has volume 100% and starts at 0:03
The 4th player has volume 60% and starts at 0:04
The 5th player has volume 20% and starts at 0:05

I'm hoping to do this with free software tools (or something cheap
like the Nero wave editor I have). The primary problem is the fading
in and out - If I can reverse that, my ear does a fairly good job of
filtering out the echo.

I was able to make a 30second piece listenable with the wave editor by
manually selecting each region that faded down and increasing the
volume. However doing this for the entire tape would take longer than
reading the book. Are there any freeware/cheap tools that can
automate this? I thought the "Normalize" function might do it, but it
did not seem to help.

By way of curiosity - if someon can explain why/how this happens, I
would be interested even though it wouldn't really solve my problem ;)

A response by email to "srauch AT umich DOT edu" would be appreciated
as I do not regularly read this newsgroup.

Regards,

Sam

[Mark D. Zacharias]

Maybe a slipping pinch roller on your player. The tapes may be damaged while
playing if this is the case.

Mark Z.


"Sam" > wrote in message
om...
> Hello. I regularly check audio books out of the library and have come
> across a handful that seem to have similar damage. In order to listen
> to the recordings, I am hoping I might be able to record the audio to
> my PC and fix it up.
>
> The damage is two-part:
>
> 1. The audio continuously fades in and out (say from 100% down to 20%
> volume - not all the way to 0% volume), on something like a 1 or 2
> second period (the period may change over the course of the tape - I
> believe it is related to the amount of tape on the spool at any given
> time). This is the more serious problem.
>
> 2. There are 1 or more forward & backward echos continuously going on.
> For example, imagine listening to 5 tape players simultaneously
> playing copies of the same tape.
> The 1st player has volume 20% and starts at 0:00
> The 2nd player has volume 60% and starts at 0:01
> The 3rd player has volume 100% and starts at 0:03
> The 4th player has volume 60% and starts at 0:04
> The 5th player has volume 20% and starts at 0:05
>
> I'm hoping to do this with free software tools (or something cheap
> like the Nero wave editor I have). The primary problem is the fading
> in and out - If I can reverse that, my ear does a fairly good job of
> filtering out the echo.
>
> I was able to make a 30second piece listenable with the wave editor by
> manually selecting each region that faded down and increasing the
> volume. However doing this for the entire tape would take longer than
> reading the book. Are there any freeware/cheap tools that can
> automate this? I thought the "Normalize" function might do it, but it
> did not seem to help.
>
> By way of curiosity - if someon can explain why/how this happens, I
> would be interested even though it wouldn't really solve my problem ;)
>
> A response by email to "srauch AT umich DOT edu" would be appreciated
> as I do not regularly read this newsgroup.
>
> Regards,
>
> Sam

[Sam]

Thanks for the information. I also received a suggestion that a
"compressor function" might be of use. The Nero software I have has a
"dynamic processor" function which performed this type of operation.
It worked well for the first tape. Unfortunately I found that other
tapes in the set were so severely damaged that the low level audio was
not even audible. Oh well.

Regards,

Sam

"Mark D. Zacharias" > wrote in message >...
> Maybe a slipping pinch roller on your player. The tapes may be damaged while
> playing if this is the case.
>
> Mark Z.
>
>
> "Sam" > wrote in message
> om...
> > Hello. I regularly check audio books out of the library and have come
> > across a handful that seem to have similar damage. In order to listen
> > to the recordings, I am hoping I might be able to record the audio to
> > my PC and fix it up.
> >
> > The damage is two-part:
> >
> > 1. The audio continuously fades in and out (say from 100% down to 20%
> > volume - not all the way to 0% volume), on something like a 1 or 2
> > second period (the period may change over the course of the tape - I
> > believe it is related to the amount of tape on the spool at any given
> > time). This is the more serious problem.
> >
> > 2. There are 1 or more forward & backward echos continuously going on.
> > For example, imagine listening to 5 tape players simultaneously
> > playing copies of the same tape.
> > The 1st player has volume 20% and starts at 0:00
> > The 2nd player has volume 60% and starts at 0:01
> > The 3rd player has volume 100% and starts at 0:03
> > The 4th player has volume 60% and starts at 0:04
> > The 5th player has volume 20% and starts at 0:05
> >
> > I'm hoping to do this with free software tools (or something cheap
> > like the Nero wave editor I have). The primary problem is the fading
> > in and out - If I can reverse that, my ear does a fairly good job of
> > filtering out the echo.
> >
> > I was able to make a 30second piece listenable with the wave editor by
> > manually selecting each region that faded down and increasing the
> > volume. However doing this for the entire tape would take longer than
> > reading the book. Are there any freeware/cheap tools that can
> > automate this? I thought the "Normalize" function might do it, but it
> > did not seem to help.
> >
> > By way of curiosity - if someon can explain why/how this happens, I
> > would be interested even though it wouldn't really solve my problem ;)
> >
> > A response by email to "srauch AT umich DOT edu" would be appreciated
> > as I do not regularly read this newsgroup.
> >
> > Regards,
> >
> > Sam

[Shpalman]

Initially I thought those tapes may have suffered partial erasure somehow -
there's no telling where library tapes may have been (left in the sun, near
strong magnets etc)...


"Sam" > wrote in message
om...
> Thanks for the information. I also received a suggestion that a
> "compressor function" might be of use. The Nero software I have has a
> "dynamic processor" function which performed this type of operation.
> It worked well for the first tape. Unfortunately I found that other
> tapes in the set were so severely damaged that the low level audio was
> not even audible. Oh well.
>
> Regards,
>
> Sam
>
> "Mark D. Zacharias" > wrote in message
>...
> > Maybe a slipping pinch roller on your player. The tapes may be damaged
while
> > playing if this is the case.
> >
> > Mark Z.
> >
> >
> > "Sam" > wrote in message
> > om...
> > > Hello. I regularly check audio books out of the library and have come
> > > across a handful that seem to have similar damage. In order to listen
> > > to the recordings, I am hoping I might be able to record the audio to
> > > my PC and fix it up.
> > >
> > > The damage is two-part:
> > >
> > > 1. The audio continuously fades in and out (say from 100% down to 20%
> > > volume - not all the way to 0% volume), on something like a 1 or 2
> > > second period (the period may change over the course of the tape - I
> > > believe it is related to the amount of tape on the spool at any given
> > > time). This is the more serious problem.
> > >
> > > 2. There are 1 or more forward & backward echos continuously going on.
> > > For example, imagine listening to 5 tape players simultaneously
> > > playing copies of the same tape.
> > > The 1st player has volume 20% and starts at 0:00
> > > The 2nd player has volume 60% and starts at 0:01
> > > The 3rd player has volume 100% and starts at 0:03
> > > The 4th player has volume 60% and starts at 0:04
> > > The 5th player has volume 20% and starts at 0:05
> > >
> > > I'm hoping to do this with free software tools (or something cheap
> > > like the Nero wave editor I have). The primary problem is the fading
> > > in and out - If I can reverse that, my ear does a fairly good job of
> > > filtering out the echo.
> > >
> > > I was able to make a 30second piece listenable with the wave editor by
> > > manually selecting each region that faded down and increasing the
> > > volume. However doing this for the entire tape would take longer than
> > > reading the book. Are there any freeware/cheap tools that can
> > > automate this? I thought the "Normalize" function might do it, but it
> > > did not seem to help.
> > >
> > > By way of curiosity - if someon can explain why/how this happens, I
> > > would be interested even though it wouldn't really solve my problem ;)
> > >
> > > A response by email to "srauch AT umich DOT edu" would be appreciated
> > > as I do not regularly read this newsgroup.
> > >
> > > Regards,
> > >
> > > Sam