Tag archives: noise reduction

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At the Subscribe 9 Conference, we presented the first version of our new Audio Inspector:
The Auphonic Audio Inspector is shown on the status page of a finished production and displays details about what our algorithms are changing in audio files.

https://auphonic.com/static/screenshots/inspector-mt-closed.png A screenshot of the Auphonic Audio Inspector on the status page of a finished Multitrack Production.
Please click on the screenshot to see it in full resolution!

It is possible to zoom and scroll within audio waveforms and the Audio Inspector might be used to manually check production result and input files.

In this blog post, we will ...

Today we released free updates for the Auphonic Leveler Batch Processor and the Auphonic Multitrack Processor with many algorithm improvements and bug fixes for Mac and Windows.


  • Linear Filtering Algorithms to avoid Asymmetric Waveforms:
    New zero-phase Adaptive Filtering Algorithms to avoid asymmetric waveforms.
    In asymmetric waveforms, the positive and negative amplitude values are disproportionate - please see Asymmetric Waveforms: Should You Be Concerned?.
    Asymmetrical waveforms are quite natural and not necessarily a problem. They are particularly common on recordings of speech, vocals and can be caused by low-end filtering. However, they limit the amount of gain that can ...

Once in a while it is necessary to convert big audio or video archives to new formats and metadata conventions, other servers, new loudness targets or apply some audio processing/restoration algorithms.
Now we offer a managed processing of archives to companies and institutions, where we adapt our algorithms and workflows to special requirements of our clients, implement all steps (no need to program the Auphonic API yourself) and perform the whole process on dedicated hardware to speed-up the conversion.

National Film and Sound Archive in Canberra, Australian Capital Territory.

What we can offer

We will adapt the algorithms and workflows ...

Our Noise and Hum Reduction algorithms are now included in the Auphonic Leveler Batch Processor, version 1.2, on Windows and Mac. Note that this is a free update!

Auphonic Noise and Hum Reduction

The Auphonic Noise Reduction algorithms remove broadband background noise in audio files with slowly varying backgrounds.
First the audio file is segmented in regions with different background noise characteristics, then a noise print is extracted in each region and removed from the audio signal. A classifier decides if and how much noise reduction is necessary.
For more details and audio examples see Noise Reduction. ...

Finally we found some time to collect a few listening examples for our audio algorithms – thanks to all the people who provided audio files!
Everything is processed automatically and you can try Auphonic yourself with the unprocessed files and will get the same results.

The official Auphonic Audio Example page is here: Audio Examples.
We will extend this page with further examples, so let us know if you have some great ones!

Listen to the following examples with headphones to hear all details.

Global Loudness Normalization

Our Global Loudness Normalization Algorithms calculate the loudness of your audio and ...

Because of so many requests we decided to release a preliminary version of our noise reduction algorithms. They are deactivated by default and you can activate them now in the production or preset form.
Additionally we included the possibility to enable or disable all auphonic audio algorithms :)

(poster from the movie Noise)

Current State of the Auphonic Noise Reduction Algorithms

The noise reduction algorithms are developed to remove constant background noise, hiss and hum in audio files with slowly varying backgrounds, such as lecture/conference recordings, static podcasts, etc.
They analyze the audio file, classify regions with different ...