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  1. I have audio ripped from a DVD that was a conversion from a VHS home video. The spectrum of the audio + the noise is as follows:

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    The spectrum of the noise/tape hiss by itself is as follows:

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    Is there any way to filter that tape hiss noise out of the audio? It looks like the noise spectrum cuts right through the spectrum of the audio I want to keep. I tried using notch filters in Audacity to notch out all of the higher frequency peaks of the noise, but it didn't make much of a difference in the overall noise level and was starting to affect the quality of the audio I wanted to keep.

    I also tried Audacity's noise filter where you give it a sample recording of the noise. It did filter a lot of the noise out, but had too big of an impact on the rest of the audio.

    I'm guessing I would have to completely wipe out all the frequencies in the noise spectrum above, which would severely affect the sound I want to keep.

    Is there anything else I can try? Am I missing something here? Would a paid software program do a better job?
    Last edited by Special K; 5th Mar 2014 at 10:00.
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  2. It will be very difficult to perform denoising on lossy compressed audio as noise is no longer signal independent.
    Usually bandithd for typical VHS deck is not higher than 8 - 11kHz and at first you can just lowpass filter for 11kHz.
    Later you can try to create very mild dehiss profile and try simulate DNR.

    fastest way to you is perform inverted operation - instead denoise do something opposite - remove signal and keep noise (most of denoising tools provide such feature - simple check mark in filter) - when you start hearing such signal you must adjust level to point where you no longer hear original signal or noise modulated by this signal - this point is your noise threshold - next step is to perform with such founded threshold denoising as usual.
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  3. Member
    Join Date: Jan 2014
    Location: Brisbane,Australia
    Search Comp PM
    Give a programme called Wave Corrector a try[wavecor.co.uk].The trial version will let you know whether or not it will work on your file,before paying for the full version.It is for audio only and is perhaps the best one for vinyl,cassettes and such.
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  4. Member
    Join Date: Mar 2008
    Location: United States
    Search Comp PM
    Perhaps the OP could post a 30 second sample so we can listen and advise further.
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