Category Archives: Digital Audio

Analog digital continuous discrete

Posted on January 16, 2023 by Nigel Redmon

Digital and analog. We often think of them, mistakenly, as equivalent things in different domains. But that’s a misunderstanding, and we often use the terms incorrectly. For instance, run a mic through a preamp and get a signal, we know … Continue reading →

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Inter-sample peaks

Posted on January 16, 2023 by Nigel Redmon

We’ve seen that samples can represent a signal with greater peak amplitude than the peak sample values. If those sample values were higher, the output would exceed “1.0”, or 0 dB full-scale—I’ll refer to these as “overs”. This brings two … Continue reading →

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Special case: perfect sine waves

Posted on January 15, 2023 by Nigel Redmon

Let’s say we want to test the output of a DAC while it passes a pure sine wave. The “pure sine wave” requirement is a bit more difficult than it might seem. In the general case, it’s not possible to … Continue reading →

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How many bits can you hear? video

Posted on April 10, 2022 by Nigel Redmon

A listening test in video form. On the plus side, it’s helpful to see the spectrum as it’s playing, and a peak meter to see how the sweeps compare to each other, and to the announcing voice. On the minus … Continue reading →

Posted in Digital Audio, Video | Tagged , , , | 2 Comments

A listening test

Posted on November 4, 2021 by Nigel Redmon

Click to play in your browser, or right-click-download to play as you wish (24-bit .wav file): multi-level sweeps.wav I call this a listening test, because it involves your ears, equipment, and even environment. Any of these can influence your limits … Continue reading →

Posted in Digital Audio | Tagged , | 2 Comments

Biquad calculator v3

Posted on September 2, 2021 by Nigel Redmon

The latest version of the biquad calculator. It also takes on the functionality of the frequency response grapher:

Posted in Biquads, Digital Audio, Filters, Widgets | Tagged | 56 Comments

Time resolution in digital audio

Posted on April 8, 2021 by Nigel Redmon

I’ve been involved in several discussions on timing resolution in digital audio, recently—honestly, I never knew it was a concern before. For example, in a video on MQA, the host explained that standard audio sample rates (44.1 and 48 kHz) … Continue reading →

Posted in Digital Audio | 5 Comments

Amplitude Modulation Principles and Interactive Widget video

Posted on October 29, 2020 by Nigel Redmon

This video demonstrates important uses of AM—and serves as a demonstration of using the AM widget.

Posted in Amplitude Modulation, Digital Audio, Video | Leave a comment

Further thoughts on wave table oscillators

Posted on January 4, 2020 by Nigel Redmon

I see regular questions about wave table oscillators in various forums. While the process is straight forward, I sympathize that it’s not so simple to figure out what’s important if you really want to understand how it works. For instance, … Continue reading →

Posted in Digital Audio, Oscillators, Wavetable Oscillators | 12 Comments

WaveUtils updated

Posted on April 30, 2019 by Nigel Redmon

WaveUtils needed only a minor change for compatibility with the WaveTableOsc update—addWaveTable changes to AddWaveTable. But I added something new while I was at it. The original wave table articles advocated minimizing the number of tables necessary—one per octave—by allowing … Continue reading →

Posted in Source Code, Wavetable Oscillators | 17 Comments