How can I split background noise and hiss from voice recording?

Taperecorded voice. Lots of background like aeroplane- and car noise, hissing when volume openened up. Only the speech needed.

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V-Man7377 years ago
(As Re-design said, Audacity is a highly recommended program, largely because it does what other sound-editing programs do, but for free.)

Sometimes, in certain recording devices, the hiss peaks at a specific frequency. You can target that particular frequency in the Equalization menu in Audacity and lowering it. It is a bit of a trial-and-error method, and you might also silence a part of the frequency of the voice, but when I've had hiss in a narrow band, I've been able to kill it while only losing a small bit of the voice quality.

Generally, however, the hiss occupies the same bandwidth as the voice, plus more. If, in this case, it is absolutely necessary to take out the hiss, you'll have to find a good analyzer - attenuator program or plugin, and I've not found any that don't cost a pretty penny, as orksecurity and Re-design said.
jemorgenrood (author) 7 years ago
Thanks a lot for answering my question.  I'm busy experimenting--starting with the easiest and cheapest way. Will take it from there.
There are two ways, one simple and one a bit more complex (and costly); the second will, however, yield far better results.<br /><br />Since the human vocal range tends to lie primarily in the 100 Hz-3.5 kHz range, you can usually get sufficient results by setting a high-pass filter at 100 Hz and a low-pass filter at 3.5 kHz, then fine-tuning these frequencies by ear until the maximum intelligibility is achieved. However, this method will really only work to filter low rumbling or high hissing - and the resulting audio will be telephone quality.<br /><br />The second method is to purchase <a href="http://www.izotope.com/products/audio/rx/">iZotope RX</a>, which is one of the best audio restoration programs I have ever used (view the demo - you'll be amazed). The regular license still plenty capable for most, while the advanced license is primarily for die-hard professionals (and the price reflects this).<br />
Pie Ninja7 years ago
Try wrapping the microphone in foam or something similar.
Re-design7 years ago
Download "audacity" it has some filters that will help you remove some of the unwanted noise. It's free and pretty easy to use. There some other free programs that will let you edit the sound file, but to do a really good job you may have to buy a better program. Just knowing what to to and how to do it would make you job easier and that would come with experience in sound editing. Try it and all you'll be wasting is some time. Good luck.
Seconded. If the normal filters aren't enough, you'll need one of the sound-scrubbing programs which examines a sample of just the noise, calculates its characteristics, and subtracts out just that much in those specific frequencies. I've used SoundSoap; not cheap but pretty effective on mechanical noises. Note that nothing reasonably priced (where "reasonable" goes up into hundreds of dollars) is going to take out things like background voices, water noises, etc, which aren't regular enough to do that kind of analysis.