Improving Audio Files

bbwannabe · 17-05-2005, 11:04

I've got some recordings of lectures that I want to improve the sound quality of. I know its not possible to get it high quality if it was recorded on low quality, but i want to remove long pauses, hisses, get the mono to stereo, just generally get it sounding better than the flatness quality I have.

Any software that you can recommend? I'd appreciate it if you could give a or small bit of info on how to use it, if you can.

Thanks.

nffc · 17-05-2005, 11:21

Audacity?

Halcyon · 17-05-2005, 11:58

Any program that lets you record and display the audio as waveform should let you easily cut bits out and re-arrange the track.
You can then also increase the audio gain, duplicate the mono channel, etc.
Steinberg's WaveLab is good and so is CoolEdit. Most of them cost a bit although you may be able to get an earlier version or trial.

bbwannabe · 17-05-2005, 11:59

Audacity seems to do the job

thanks nnfc. Not sure how to get it converted to stereo though.

Thanks for those alternatives Halcyon.

SMHarman · 17-05-2005, 12:44

goldwave

Flubflow · 17-05-2005, 13:15

For removing hiss, there is/was a good directX audio plugin from Sonic Foundry whereby you sample a section of just the hiss and that is used as a "noiseprint" which is then subracted from the audio. It is not perfect but it is often better than simple EQ filtering. The trick is not to try and remove too much at once with one noiseprint otherwise you sometimes get other strange artefacts in the processed audio (which is probably OK if it is only the speech you are trying to make more legible for dictation).
You can also use harmonic enhancer/exciter type plugins to generate a crisper top end that was not there in the first place. There are also dedicated speech processing plugins too which use a combination of harmonics and filters to enhance the spoken word but these are probably more for fine tuning a good recodring rather than restoration of a very bad recording.