Questions tagged [sound]
The sound tag has no usage guidance.
274
questions
1
vote
1
answer
1k
views
How can I connect multiple microphones to my computer (more than 4) and process the outputs independently? [closed]
I am trying to create something like a heat map for sounds originating in a classroom to study the discussions inside the classroom. For this I am instaling directional microphones in various parts of ...
- 11
22
votes
5
answers
3k
views
What are the audio equivalents of images like "Lena", "Mandrill", and "Cameraman"?
I don't know what to call these images, but they're very often used in the image processing world as standard examples to show the output of a particular operation. Here's a link to the page ...
- 321
-1
votes
1
answer
608
views
how to read full input signal with STFT in matlab
Please help! I am trying to figure out why in the code i have below my input signal is being cropped but in the code I have a full signal created. The white noise created is 5000 samples for the right ...
- 61
1
vote
1
answer
104
views
What does it mean for audio to be 'sped up'? How can I undo it?
I very simply have a .wav audio file, but there is a note with it that says "This audio has been sped up by 10x".
I am wondering, what does it mean exactly from a signal processing perspective for an ...
- 1,782
0
votes
1
answer
7k
views
how to apply Short-time fourier transform to code in matlab
Please Help, I have a white noise signal that I created and need help to apply the Short-time fourier transform to my code so that it can do the bandpass filtering. I am trying to put it in the code ...
- 61
0
votes
2
answers
1k
views
Android: fundamental frequency
I want to find the fundamental frequency for human voice in an Android Application. I want to use autocorrelation method. My code is this:
...
- 101
0
votes
1
answer
342
views
How to Concatenate white noise signal and applying bandpass filter matlab
I created a white noise signal. I am trying to use the array I have created with the white noise to play in 2 channels. When the left channel I was trying to have 5000 samples and the right will have ...
- 61
2
votes
1
answer
412
views
Time-varying waveform
My situation is as follows: i am trying to generate a waveform the hard way, by constructing the samples one by one and then saving the result to a .wav file using Python.
When the frequency is ...
0
votes
1
answer
117
views
How to store the signal in a variable and plot the signal in MATLAB
I am trying to store the signal I have created in a single variable and graph the signal in two subplots in one single graph, one for left channel, one for right channel.
...
- 61
0
votes
1
answer
1k
views
How to add repeated beeps to sound created with a pause in between each beep in MATLAB
I have 2 sounds that I created and trying to make them beeps. Maybe 4 or 5 repeated beeps but have a pause in between each beep but make it still part of the signal. I think I have it so that the ...
- 61
2
votes
2
answers
2k
views
Creating 2D array to play audio in left and right channel in matlab
I'm new to matlab sound processing and I am trying to create a 2D array for the sound code below. I have to make the sound have 400 samples(i.e 10ms) at 20hz, but having trouble getting the code to ...
- 61
1
vote
1
answer
656
views
Resonant peak frequencies for phaser effect
I have a conventional phaser setup with allpass filters and feedback.
I can calculate the peaks frequencies of the phaser when the allpass delays are set to 1 (then they work as simple one sample ...
- 11
1
vote
2
answers
614
views
Separating excitation from filtering for sound sythesis
From my days at college I rememeber that LPC splits a signal into a series of slowly changing filter coefficents and an audio-rate residual error signal, such that the original signal gets reproduced ...
0
votes
3
answers
473
views
How to delay a signal by D degrees
I read in a paper that a sound signal can be delayed by D degrees. How can such a thing be possible? Isn't sound signals expressed only in terms of the time axis?
Thanks in advance
- 336
0
votes
1
answer
101
views
what is standard acoustic volume
In Audio Experts book, it's given as
Sound pressure meters must be calibrated at factory to a standard acoustic volume.
So what doth this ...
- 207
2
votes
1
answer
5k
views
Time-frequency representation of sound signal using Matlab
I am currently doing a project on sound signal processing by using MATLAB. I have a problem regarding creating the command line so that I can get a graph containing frequency by its time. But this ...
- 21
1
vote
1
answer
207
views
Fourier Transform for frequency analysis
I applied Fourier transform on a sound (PCM generated digitally with sin function) and frequency detection is accurate. However, if I play the sound and record it, and then apply a Fourier transform ...
- 121
0
votes
1
answer
620
views
Q value for a high pass filter
How to calculate the Q value for a high pass filter ?
Ps: I'm a beginner in signal processing, so please put it in simple terms.
0
votes
1
answer
53
views
Frequency filtering - Audio
Sound are digitalized in computers as an archive with its intensity amplitude at the given time. I want to ask a very simple question about frequency filtering. How it's done, if there's no frequency ...
2
votes
2
answers
334
views
Need help with FFT results
I am playing around with FFT and cant seem to get the expected results. I have a sound clip that i recorded from a mic placed on an analogue clock. So it has a sound every second.
...
- 21
3
votes
1
answer
2k
views
Colored noises: Stationary or non-stationary?
I know for sure that white noise is considered as a stationary sound, but is that true for the rest of them? http://en.wikipedia.org/wiki/Colors_of_noise
Also, can we meet some of these sounds in ...
- 31
0
votes
2
answers
990
views
Pitch class profiling
Currently, I am developing a piece of software for chord recognition. There are FFT and pitch class profiling on it. I tried using the pitch class profile proposed by Takuya Fujishima, but the result ...
- 131
0
votes
2
answers
435
views
Why do we follow Shannon's Theorem in audio sampling?
My professor told me that in sampling a signal, is not usual to respect the Shannon theorem because the interpolation formula contains sines and fractions which are difficult to calculate with a ...
- 103
-1
votes
1
answer
110
views
1
vote
1
answer
4k
views
Separating two sound file frequencies using bandpass filter matlab
can someone please help me? I have a project to implement a superheterodyne transmitter and receiver without using matlab functions that modulate. The first part which I can't seem to get right is the ...
- 11
2
votes
1
answer
943
views
How to compare 2 matrices of MFCCs, keeping the time information
I have a corpus of several thousand sounds. Now I pick a sound sample S, and I want to find in my corpus the sound S' that is the most similar to S.
The application is for music, for a composition ...
- 283
0
votes
2
answers
486
views
How to decipher this Microphone sensitivity Chart for Choosing a SPL meter
I have a mic having sensitivity chart as below which has relative dB on y-axis showing
1V/0.1Pa
what does this convey how to read my mic's sensitivity
a document on microphone sensitivity from ...
- 365
1
vote
2
answers
462
views
Speech Enhancement Libraries
Is there any speech enhancement algorithm library?
I need to process a sound to voice recognition, and I want to remove noise from audio source.
- 111
1
vote
3
answers
6k
views
Easiest Beat Tracking Algorithim
I want a relatively easy to implement but relatively reliable algorithm for detecting beat locations in an audio file.What I am aiming to do is get the location of the closest beat to a particular ...
- 326
2
votes
1
answer
260
views
Detecting presence of music in ambient sound
I am hoping to create an application that would listen to ambient sound and detect if music is being played. It is not important to identify the music being played; just detecting that some music is ...
- 121
3
votes
2
answers
142
views
Acoustic measure of a specific room
I would like to make an acoustic measure of one room, so I can compare it with a acoustic measure of some other room. Then compare these data. So when I take an acoustic measure of the first room ...
0
votes
1
answer
1k
views
Why only take 205 sample when using a sample rate of 10khz or 8khz?
I've often seen i my DSP book, that when they record a sound, they use a sample rate at 10khz or 8 khz, which makes sense since the fs is 2 times bigger than the sampling signals max freq.
What i don'...
- 11
0
votes
1
answer
171
views
Sound card for recording audio
I need to record sound using 2 (or 4, eventually) microphones and then calculate the time delay of arrival of sound at the different microphone pairs. But first, I need a microphone array. And since I'...
0
votes
2
answers
399
views
Measure and simulate non-linear distortion
We can capture frequency response, phase response and reverb in recording of impulse response. Then we can use it to simulate audio system and/or space by convolving it with dry audio signal.
Is ...
- 93
1
vote
2
answers
849
views
Audio interface or External sound card?
I want to create a microphone array that can be connected to my laptop. Previous discussions in stack exchange and other forums suggested me to get a USB audio interface. I would want to do a lot of ...
0
votes
1
answer
61
views
Algorithm to change an already sampled guitarstring to sound like it was a bit damped by the hand [closed]
I'm trying to simulate the damping of the hand on a guitarstring on an already recorded/sampled open guitarstring sound. I've been trying to use low pass filter and had a moving frequency range but ...
- 101
8
votes
1
answer
25k
views
Why should one use windowing functions for FFT?
So I just revised my pitch calculation algorithm using a harmonic product spectrum algorithm. I was just curious about why this explanation of Harmonic Product Spectrum states that you need to ...
- 291
0
votes
1
answer
488
views
Modelling propagation of sound wave by particle simulation
How might one model the propagation of a sound wave through a 3D environment with obstacles in it?
My initial thought would be to use freely moving particles that repel one another; with sufficiently ...
- 1,319
0
votes
3
answers
111
views
Auditory receptive field mapping
The Wikipedia page on sound localisation states:
Localization accuracy is 1 degree for sources in front of the listener
and 15 degrees for sources to the sides. Humans can discern interaural
...
- 1,319
1
vote
1
answer
767
views
Comparing two sound files in embedded-systems (C language)
what would be the most efficient ("cheap" in terms of system resources etc.) way to compare 2 sound files?
Here is the scenario. Sound A comes as an input. There is sound B stored in memory. We need ...
- 113
3
votes
1
answer
295
views
How to add more cowbell?
Remember that Christopher Walken skit on Saturday Night live where he told the band “it needs more cowbell” https://en.wikipedia.org/wiki/More_cowbell ? This site automated it http://www.morecowbell....
- 255
3
votes
2
answers
191
views
Two generated tones creates a side tone - how to avoid the side tone
I'm trying to create two tones at different frequencies. So I have one tone at 15000 Hz and one at 15400 Hz using Audacity. The problem i'm running into is there is a third tone created at a much ...
- 47
1
vote
2
answers
2k
views
Direction of sound using microphone array
I want to estimate the direction of arrival of sound (angle in a 2d plane) using a microphone array. I'm hoping to follow a time-delay based method using a 4 mic array. The method requires me to find ...
0
votes
1
answer
2k
views
How to convert text into wave [closed]
I am trying to transfer text data via sound wave between two android phones. I am a newbie and would like to know how to proceed with it. I am stuck at the very first step on how to modulate text data ...
- 1
0
votes
2
answers
2k
views
voice pattern matching algorithm
My idea is to find a word in wav/mp3 files. It is just one word.
I have a database with a few hundred songs.
I am looking for pattern matching (this is not an exact pattern) it can be an word i ...
- 215
0
votes
1
answer
66
views
fliter doesn't filter
In this code I try to decompose music from singer sound with wfilters but when I hear it it is still mixed where Iam I wrong ?
...
- 33
0
votes
2
answers
598
views
What's the best method to extract vocals from music?
I want to achieve something like this https://soundcloud.com/user7421656/sonicworx-isolate-preview .
I've researched it and a few papers mention the use of "descriptors" on the audio and use ...
- 25
1
vote
2
answers
387
views
Measuring how "non-noisy" a sound signal is
Given a sound clip (whose source is an FM radio signal) I'd like to measure how different from background noise (the "in-between channels" noise) the sound clip is, so that I can compare the "non-...
- 203
15
votes
4
answers
30k
views
How to compute dBFS?
I asked myself how to compute dBFS (dB full scale) from a value of sample between 1 and -1?
and in general?
- 541
1
vote
2
answers
164
views
Generating Music Tones, How to handle when tones overlap? (16bit samples) [duplicate]
If i add the two tones then the result if two peaks are added together will be greater then the the sample max (2^15).
For the life of me I couldn't think of the right words to google. Think i have ...
- 25