suggestions-intelligibility with old time radio

[markeh]

I listen to OTR on my ipod, and using that in my car.

These recordings are the polar opposite of high fidelity - most recorded before the invention of magnetic tape on shellac transcription discs - think AM radio sound on a bad night. Most of those that I get are at fairly low bit rates - 6mb for a full 1/2 hour, which seems appropriate given their recording quality

I'm trying to increase their intelligibility, not necessarily their musical quality. Most would be in the category of "spoken word."

One way of doing this is with changing the frequency response, as in a graphic equalizer. But another idea (which would like to try) is using volume compression - using the "adaptive" setting on the volume normalizer. (My preference would be a player that does the same thing without modifying the file, but I don't know of any.)

1. I would appreciate any suggestions of what settings on the adaptive DSP settings would work best. In particular, how do I set the "window length"?

2. I'm guessing that the process involves decoding and recoding the mp3. Is there a way to set the converter so that it picks the same bit rate/sampling - neither larger or smaller. I could easily see turning this loose on a directory of shows, not all coded exactly the same way. No reason to use more space than the original, and I don't want to throw away any information.


thnx,

[Spoon]

Re: suggestions-intelligibility with old time radio

Yes everything needs to decode the file and re-encode it.

The larger the window length the slower the volume changes, smaller window more agressive changes.

[markeh]

Re: suggestions-intelligibility with old time radio

Yes everything needs to decode the file and re-encode it.

Is there a setting that matches to original file?? I would like to point the converter at a large number of files which might be at different bit rates. The idea is that the output matches the input sampling rate.

The larger the window length the slower the volume changes, smaller window more aggressive changes.

Do you have a suggested setting for spoken works, like OTR??

thnx,

[Spoon]

Re: suggestions-intelligibility with old time radio

There is no real setting which matches the original, each time there is an encode a little quality is lost, so if you had:

128kbps

then reencode to 320 kbps, it will be closer to the 128kbps than if you reencoded with 160kbps. We are talking small differences though.

The default values are a good starting point.