I use sound forge to do that, and it works great with a filter of 50Hz
without distortion, as long as the source is distortion free.
Not using SR, sorry, but in SF, copy all the values for the 60Hz four
stage filter, but make them 50Hz, and it is amazing!
The ASPH cassette recorders in the 80S and 90S produced 70Hz tones, and
once in a while you'll need to use 55Hz filters, but they do a
remarkable job when properly tuned.
-----
Curtis Delzer, HS.
K6VFO
San Bernardino, CA
On Mon, 12 Dec 2016 18:33:27 +0000
Sheila Winther <Sheila.Winther@xxxxxxxxxxxxxxxxxxx> wrote:
We are converting our analog talking books to digital. The analog recordings
have tone indexing mixed into the audio. Has anyone found a good way to
remove the low frequency tone without destroying the voice audio? I use
Audacity noise reduction for background tape hiss, but if I change the values
of the noise reduction enough to effect the tone, it really makes the rest of
the audio sound over processed. Any help will be much appreciated.
Sheila Winther
Volunteer Services Coordinator/Recording Studio Manager
Idaho Commission for Libraries
325 West State Street
Boise, Idaho 83702
208-334-2150
www.libraries.idaho.gov<http://www.libraries.idaho.gov>
