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Audio, or in terms of signal processing, an audio signal is an analog or digital representation of sound, typically as an electrical voltage.

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Artefacts from playing ultrasound through PA system

I encode data in audio by energising 5 frequencies between 17.5kHz and 19.5kHz: I play the ...
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22 views

modify main sound with second sound (matlab)

So i have 2 sounds. Main sound and second sound which represents "parking garage" effect. So i want to modify main sound that sounds like it's playing in parking garage. ...
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7 views

Difference between Spectral Centroid and Spectral Subband Centroid

I want to ask about the difference between Spectral Centroid which I see the definition in Wikipedia Spectral Centroid and Spectral Subband Centroid in this paper [2]. [2] Paliwal, Kuldip K. "...
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1answer
51 views

Write a 440 Hz Sine Wave to .wav-File using Python and SciPy [closed]

This is my first post on DSP.SE! I'm a student in Computer Sciences and am just getting started with Signals and Systems, thus getting in touch with discrete signals and analyzing them. I wanted to ...
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1answer
44 views

WAV FILE FORMAT

I'working with esp32 and for some project I need to know something about wav files. I saw into many wav files with HxD and play them with Audacity. Still I do not understand why Audacity play silence ...
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2answers
262 views

Estimating effect of filter on headroom

I am working with beamforming algorithms for speaker arrays. One of the problems we face is that we need to estimate the maximum amplitude of our test signals after we applied FIR/IIR filters to them. ...
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0answers
15 views

What needs to be measured to compare two speech signals? [closed]

I have two speech signals coming from two different people. I want to find out whether or not both people are saying the same phrase. Is there anything that I can directly measure between the two ...
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0answers
14 views

Cosine distance between two MFCC vectors is giving unreasonable values [closed]

I am comparing two speech signals. I extracted the MFCC features , performed DTW on them, aligned them accordingly, and calculated the average cosine distance between every two feature vectors. ...
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0answers
29 views

How would I change this C++ delay to work more like this Reaktor one? [closed]

I am currently using a C++ audio delay effect from Maximilian. It works well, but it lacks some basic wet/dry and pre/post 0-1 crossfade variables which I would like. Here is a model of what I want ...
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0answers
27 views

Sound recognition within an audio signal

I'm trying to do some tests in Android. The phone's microphone is continuously listening, and whenever a balloon is blown, I would like to detect it. There are of course other ambient sounds/noises. ...
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1answer
14 views

Is there a software tool or web service to detect problems in speech recordings?

I am looking for a software/library or a web service/API that can detect problems in short samples of recordings of speech. For example echo, clipping, pop, background noise... Do you know of any ...
0
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1answer
29 views

how to create a harmonic mask from fundamental frequency?

Using an algorithm that gives the fundamental frequency across time, example https://www.mathworks.com/help/audio/ref/pitch.html (or some other one?) how would I then use that, to create a harmonic ...
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2answers
36 views

Find original Hz of converted audio-file?

I have received an audio file which is 44.1kHz wav. My ears suspect this audio clip was originally lower than 44.1, and encoded to 44.1 later, much like re-encoding a 720p video to a 1080p video. Is ...
0
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1answer
30 views

Find identical audio signal

I have a long audio file (in wav) and a short audio file (in wav) that has been copied from the long file. Now I need to find the correct location where the short signal has been copied from. I tried ...
2
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2answers
49 views

Measuring microphone Signal to Noise ratio (SNR) with A-weighting

Foreword: I have already read Applying A-weighting and user @endolith's A-weighting code I would like to measure the SNR of a microphone with the same method applied by the main manufacturers, that ...
0
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2answers
75 views

Modeling the human perception of noise

Add together some sinusoids with irrational or "nearly" irrational frequency ratios, and you get something pseudoperiodic. If there aren't too many, you can hear that it has only pitched components, ...
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1answer
55 views

Find filter coefficients to model a device using its measurement

I am trying to realize a digital filter that has the same freq. response of an existing speaker. I have fed an audio sine sweep to the speaker and measured the speaker output, both at 48kHz. Then I ...
0
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0answers
17 views

ADC module that can process 8 audio channels

i want to construct a digital audio mixer capable of receiving 8 audio channels and output the combined audio signals in real time. How can i process 8 live audio channels at the same time with ...
0
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1answer
40 views

What is the proper way to implement a real time spectrogram?

I am trying to implement a real time spectrogram and I am not sure that I am implementing it the right way. First I decided to use Matlab, I was taking a short recording of lets say 0.1 seconds and ...
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1answer
45 views

Extracting feature from audio track using DWT

Our teacher gave us an assignment: Write a program to transform an audio track to time - frequency domain, and create a vector include at least 4 features extracted from transformed output signal. I ...
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1answer
33 views

4-phase FIR LPF in MATLAB

I'm trying to create a low pass FIR filter using the coefficients I found in ITU 1770-3 on page 18. This is the last piece of the puzzle for an audio loudness metering algorithm I'm working on. I'm ...
0
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1answer
51 views

Frequency detection in audio and what parameter or set of parameters help/limit frequency detection

I'm trying to learn audio and voice/speech processing techniques out of interest. I intend to learn, experiment with algorithms and design, implementation of such systems, frameworks using programming ...
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0answers
16 views

Integrating values in a matrix in MATLAB- Audio Loudness Meter

I'm trying to implement an algorithm in MATLAB as specified by ITU-R BS.1770-3. The goal is to measure loudness of an audio file in 3 different ways: un-gated LKFS, gated LKFS, and true peak. So far I ...
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0answers
35 views

Filtering Audio Signals in MATLAB

I'm trying to apply a filter to an audio signal in MATLAB and having some trouble processing it. So far, I have a transfer function that describes a K-weighted filter, and I am able to create a bode ...
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0answers
27 views

Make an envelope smoother but keep the sharp attack

I have a signal x for which I would like the envelope. I have taken the Hilbert transform (like in this question): ...
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1answer
92 views

Separate two sinusoids with very close frequencies (5 Hz difference) in a 44.1 Khz audio signal, with good time-domain resolution

Here is an audio signal which is a mix of (WAV file available here): a 2000 Hz sinusoid, beginning at 1.00 sec, without fade-in/fade-out a 2005 Hz sinusoid, beginning at 1.031 sec, with a slow fade-...
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0answers
15 views

MFCC Feature Reduction for Similarity Search

I'm working on creating song level features for music tracks. ...
0
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1answer
23 views

sound pressure level(SPL) from .wav of a heart sound [duplicate]

I am trying to get SPL from .wav of a heart sound but I dont know what kind of data I would need. in the other questions, some said calibration factor but I couldn't find it in the manual of the ...
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0answers
14 views

Modelling Psychoacoustic bass boost

I am motivated to try out psychoacoustic bass boost to my DIY speaker. Now the most popular reference comes from Maxxaudio which has a commercial plugin but I was looking for something off the shelf ...
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2answers
62 views

Recommended resources for noise reduction

I know the question What Resources Are Recommended for an Introduction to Signal Processing (DSP)? and I have already read some general DSP books, such as Rick Lyons's "Understanding DSP," and also ...
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0answers
33 views

What are good sources to read about nonlinear transfer characteristics, particulary in audio devices?

I'm having a hard time trying to find books and articles about nonlinear transfer characteristics appearing in analog audio devices, e.g. tape, transformers, different kinds of tubes, etc. ...
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0answers
90 views

Frequency translation with FFT

I'm new to DSP and I would like to make an SDR receiver. For this I want to shift bins in the frequency domain in order to bring to 0Hz any portion of the base band spectrum (I know that there are ...
0
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1answer
65 views

Convert 96 Khz to 48 Khz audio: is this simple downsampling method ok?

I have an audio signal x sampled at 96 Khz. I have already lowpassed it with a cutoff somewhere between 20 Khz and 22 Khz, so there should be nothing left of ...
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36 views

creating custom waveforms equations for sounds

Someone recommended I ask this here... Found a nice example of some equations here: https://sound.stackexchange.com/questions/25163/do-you-know-other-wave-equations But unfortunately stackexchange ...
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2answers
81 views

Any way to reverse engineer professional audio algorithms or those in e.g. rack units?

Any way to reverse engineer professional audio algorithms or those in e.g. rack units? In order to study how they're implemented? Not suggesting to steal ideas, but as education.
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3answers
38 views

harmonic algorithm for extending compressed bandwidth of audio file

I just found this site and feel at home :) I've been playin around with python and some compression ideas and was wondering if there's anything like what I am trying to figure out... I've noticed ...
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1answer
66 views

What is the name of this very simple spectral subtraction technique?

Let $S = X + N$ be the sum of two audio signals $X$ and $N$ which are both stationnary (let's think X is a constant volume 440 Hz sinusoid and N is constant volume noise). If the sum S has a -20 dB ...
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0answers
24 views

Generating values of EQ presets

I am using this project in Rpi - bmc0/dsp It allows to set various effects and DSP setting to the entire audio stream of the device. I wanted to get some common preset values like Pop, Dance, Rock, ...
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23 views

Basic Acoustic Tracking with Sensor Fusion for Automatic Gain Control

I'm trying to apply automatic gain control to an audio source emanating from two speakers by measuring the loudness of the signal in the presence of noise at multiple sensors. The sensors can move, ...
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2answers
54 views

How can I calculate what a recording would sound like if it was played through my speakers and mic?

I am trying to isolate the sound of someone speaking while music plays back in a noisy environment. I have multiple speakers and a microphone in my system. I am able to play back just music and ...
0
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1answer
61 views

What does it take to design a 4th order band-pass filter with -24dB/Octave?

I would like to implement in software the same isolators that the Pioneer EFX-500 features: The manual says the following about the isolators: High-performance 3-band Isolator Function [Fourth-order ...
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1answer
23 views

Audio Processing Used in Voip Mobile Apps

I am new to VoIP apps and am learning about the various audio processing that are applied in such apps. I have looked at Linphone and ...
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1answer
44 views

About speech preprocessing in mobile phones

I understand that cell phones transmit speech signals in digital form through 2G/3G or other standards. But I could not find anything about the signal processing method lying in between the analog ...
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2answers
64 views

Is it accurate to say in digital audio that, when a fader is down, then its value is “-$\infty$”?

Is it accurate to say in digital audio that, when a fader is down, then its value is "-$\infty$"? What has confused me is, whether it's really $-\infty$ or some lower bound of the amplitude. it could ...
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0answers
160 views

Cocktail Party Problem — audio source separation

I am trying to solve the Cocktail Party Problem. I am trying to separate these two mixed audio files: mixed 1 [WAV] mixed 2 [WAV] into 2 separate audio files that contain the 2 original sources, ...
2
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0answers
60 views

Digital vs Analog music [closed]

What are the different constraints for mastering audio content for either Vinyl or CD? By the way, I'd like to know if there're any papers or documents, with a comparison between different digital ...
0
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0answers
26 views

Detecting a whistle in audio clip or stream?

I have a 5 minute audio clip (~ 50MB) recorded by placing a speaker outside. The goal was to capture a whistle and do further analysis that would help me write code to eventually detect the whistle, ...
2
votes
1answer
77 views

How to delay an audio signal by 1 microsecond? [duplicate]

I have an audio signal sampled at 44100Hz. I want to delay this signal by 1 microsecond (and maybe even less) for a steganographic purpose. Now if I delay it one sample, the corresponding time delay ...
1
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1answer
50 views

How many psychoacoustical critical bands are there?

I understand that the human ear works as a band-pass filter and I have doubt regarding the number of such bandpass filters in the filter bank. I came across these two possible explanations of how it ...
0
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2answers
53 views

Software to extract frequency spectrum data from an audio file

I've been trying to learn how computers recognize musical notes, and I found apps like spectrogram which shows the frequency spectrum of a sound, but what I need is the data which is plotted or the ...