Questions tagged [sound]
The sound tag has no usage guidance.
0
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2answers
47 views
Need help cleaning noise
I have been recording sound sample from mouse vocalisations and noticed that a background noise appeared in the recording room. the noise is clearly visible in the spectrograms of the recordings as ...
0
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0answers
25 views
Is there a big data solution to analyses hydroacoustic data? [closed]
I'm looking for tools to work on hydroacoustic data, basically I want to measure biomass volumes from using the data recorded from echo sounders, the final product I´m aiming to is a biomass heat map, ...
0
votes
0answers
9 views
need help cleaning a sound sample from a constant (stationary) background noise
I have been recording sound sample from mouse vocalisations and noticed that a background noise appeared in the recording room. the noise is clearly visible in the spectrograms of the recordings as ...
0
votes
1answer
21 views
How to use the iircomb filter in matlab
I have a sound file that needs filtering which looks like this:
Hence I think that I have noise spaced equally at 832Hz. i tried to use the iircomb filter taken from mathworks website and i managed ...
0
votes
1answer
35 views
Distortion in sound after multiplying frequency spectrum by constant
I make a simple sound equalizer that operates in frequency domain and lets user to adjust frequencies in sound by using 4 sliders. The first one responsible for 0 - 5kHz, the fourth one for 15-20kHz.
...
0
votes
1answer
32 views
How do I know what is causing the noise in my signal
I have a noisy audio file, available here (It is safe to download if you wish to)
https://ufile.io/pstrt
Now, I inspect it in matlab:
And then i plot it on normalised frequency:
Now I need to ...
2
votes
3answers
483 views
What is the (approximate) function for amplitude of a plucked string over time? Does it differ between string types?
Impetus: I'm currently working on my first synthesizer, after many years of playing with them. I've just added an ADSR envelope to modify the gain, but for some reason it sounds wrong to me. I've ...
-1
votes
0answers
33 views
Improving efficiency of the Prony's method
I employ the Prony's method on very complex signal with a relatively high amount of noise (signal-to-noise ratio of approximately 20 dB), predominantly in the high-frequency range (above 5 kHz) while ...
0
votes
1answer
37 views
Is there an intensity estimation algorithm working solely in time domain
Given a second of sampled sound pressure signal, speed of sound and medium density, can the average sound intensity be estimated without performing DFT, that is in linear time by simply traversing all ...
0
votes
1answer
38 views
How to differentiate an empty aerosol from a full one using only sound measurements?
The challenge I have is to detect an empty spray container using sound measurements only, since I can't place any sensor directly into the container because of the mechanism that tightens it.
My main ...
0
votes
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.
...
1
vote
1answer
33 views
make a voice sound signal play faster
Suppose $x(t)$ is a signal containing a voice. How can one derive a signal playing the same voice faster.
I tried $x(t+\lfloor{100t\rfloor}/100)$ to double the speed; But it adds a buzz sound. Is ...
0
votes
1answer
21 views
How does a sound card translate amplitude values to sound when playing WAV/PCM/FLAC files?
I'm reading the documentation for WAV files (and importing them in C++)It seems like 44100 amplitude (this can change, and is specified by the WAV header) values get sent to the sound card every ...
0
votes
1answer
166 views
How to measure acoustic pressure level under water with a hydrophone?
this is my first post here and I am also new in signal processing.
Let's say I have a hydrophone with amplifier which is connected to a sound card plugged in to a computer. I gather the sounds to a ...
0
votes
2answers
83 views
How to convert a sound signal function to wave file? [closed]
I am new to understanding sound signals. A sound signal, as far as I know, is a real function of time $x:[0,\infty)\to \Bbb R$. For example, $x(t)=\sin(t)$ is a sinusoidal signal.
What is $x(t)$. For ...
0
votes
0answers
18 views
Seismology - PPV / VDV from geophone waveform data
I'm using an inexpensive seismometer to try and measure the effects of local HGV traffic on buildings. The device is connected to a Raspberry PI that has a Cirrus Logic Audio Card. The signal is fed ...
3
votes
1answer
103 views
Proof-of-concept for active noise cancellation to block consistent low-frequency HVAC noise transmission
Background
We live in a multi-unit building where each unit's HVAC system/closet is located directly across a party-wall from the neighboring unit's bedroom, and adjacent to a shared external curtain ...
1
vote
2answers
107 views
Is spectral centroid enough to measure brightness?
i'm new in this group and i'm studying a sound signal.
I have used FFT for extrapolate frequencies and see the harmonics of this sound.
I have to compare this sound with another similar sound and find ...
0
votes
1answer
42 views
Detecting whether reverb is present
I have two different audio short samples of an instrument playing. If one of the samples has a reverb effect applied, how easy is it to detect which sample has reverb? Is this possible?
1
vote
3answers
90 views
No-lag causal bandpass filter kernel formula
Can anyone point me towards a formula for a good (for any values of "good") no-lag causal bandpass filter?
I am doing sound processing and I need to identify starting points of certain sounds (target ...
0
votes
1answer
84 views
Measuring Amplitude of sound wave FFT
Please, pardon my ignorance. This may be a simple question, but I am still unable to explain what is happening.
I am using a turtlebot to listen to sound emitted from a stationary sound source.
My ...
0
votes
1answer
91 views
Uncertainty Relation between time and frequency
Typically, humans can hear sound waves in the frequency range 20 Hz to 20 kHz. If one wants to make digital record of sound such that no audible information is lost, what is the longest time interval ...
3
votes
2answers
125 views
Pitch perception - Why does our ear not directly detect the missing fundamental frequency?
My motivation for this question is related to biological phenomenon of our inner ear, so I initially posted in the biology community, but I suspect the answer has a DSP explanation, so I figured this ...
0
votes
0answers
13 views
Signal processing methods for identification of multimedia descriptors for feature extraction (semantics)
It is said in https://www.amazon.co.uk/Multimedia-Semantics-Metadata-Analysis-Interaction-ebook/dp/B005E8AG66 that
While there has been a lot of work in the signal processing research
community ...
0
votes
1answer
22 views
Repair audio file [closed]
I have an audio recording, recorded using my smartphone. The audio format is .aac and is around 90 minutes long.
The first 65 minutes of the audio file plays excellently, but then the audio is kinda ...
-1
votes
2answers
467 views
How can I calculate Reverberation Time (RT60) from the Room Impulse Response using Python?
I have the following Room Impulse Response(RIR) in wave format here. I wanted to calculate Reverberation Time (RT60) of it by plotting its Energy Decay Curve using this Python code.
The RIR is ...
0
votes
0answers
42 views
Sound and Vibration Signals- Frequency content
I am not sure if here is the right place to ask such question. I am missing my physics classes right now and maybe you guys can help me. Or give me some tips for researching the theme (biblio)
I am ...
0
votes
1answer
50 views
is there a way to apply a median filter diagonally?
For example, some studies show how to smooth a spectrogram with a 2D median filter vertically and horizontally (along time or frequency). My question is how would I apply 2D median filter along the ...
0
votes
0answers
18 views
is there a way to separate transients by length?
Suppose we have a mixture audio signal, consisting of very short transients and some that are a bit longer (in ms, or s) along with other material, like harmonics, etc. But focusing only on transients,...
0
votes
1answer
259 views
How does it go about implementing pitch shifting without affecting the duration or speed on matlab? [closed]
I am creating a project that will record a sound sample from the world, for example, a bird's chirping. And then through pitch scaling, I could create different notes.
I first tried to change the ...
4
votes
1answer
163 views
Algorithm for identifying beat grid in music with non-constant tempo
Are there any algorithms for automatically fitting a beat grid to a song (tempo matching) when the song has a slowly changing tempo or BPM?
The output would be a vector of onsets.
Here's a picture ...
0
votes
0answers
25 views
When we play several audio streams what is responsible for mixing them?
When we play several audio streams what is responsible for mixing them in single audio playing via speakers?
Clearly it should be either OS combining the sounds or hardware getting multiple data ...
0
votes
1answer
26 views
How to model airborne sound channel
I'm making a soft demodulation/decoding to communicate a microphone and a speaker in short range. I have to calculate the LLR using my constellation and the airborne sound channel probability density ...
0
votes
1answer
999 views
Mathematical equation for the sound wave that a piano makes
Is there a mathematical function that can output the sound that a piano makes at different frequencies?
So if the simplest equation for a sound wave (at a given frequency and for a given sample rate) ...
0
votes
0answers
24 views
Intensity to voltage
I am using a formula for Interaural Intensity Difference. link
So if one ear should hear 0.8 of the intensity of other ear.
How would that translate into reduced voltage for the headphone speaker?
...
3
votes
1answer
57 views
How exactly does sound get encoded by a cochlear implant processor?
I've been wanting to know more about how sound is processed by a cochlear implant processor, how they are programmed, and how they stimulate the magnets and electrodes inside.
How do you take pure ...
2
votes
0answers
255 views
PortAudio: sound fade in/out by scaling sample data
I've done already some fade in or fade out effect in portaudio, but that is not working properly.
My callback function:
...
0
votes
2answers
100 views
recognize unwanted sounds, noises, and deleting them algorithm
I have a function that I need to use denoise algorithm on.
What I thought is to divide it to smaller parts and then use Fourier Transform on each one of the parts, but I am not sure what to do next.
...
4
votes
1answer
368 views
Polyphase Filter decomposition. It is not working
So, I want to do a polyphase implementation of a filter bank (I had problems with it since the beginning and I already asked for help to the community in the past, indeed: Norm MPEG-1 Layer III (Mp3) ...
11
votes
3answers
2k views
Transmit data through sound between 2 computers (very close distance)
I'm writing an example on transmitting data through sound betwwen 2 computers. Some requirements:
The distance is very close , i.e the 2 computers are basically adjacent to each other
Very little ...
1
vote
2answers
62 views
Custom ringtone sounds good on computer, can't be heard on phone [closed]
I did a ringtone using Audacity and then used this website to convert to mp3. I sent this mp3 file to a friend who said he couldn't hear it well. I have an iPhone so I converted it to m4r. Both the ...
0
votes
2answers
93 views
How to label sound events in noisy .wav files
I'm trying to find a way of automatically identifying birdsong in phone-recorded sound files (1min long). Currently the algorithm I'm using doesn't label all of the events I want it to. (it is ...
0
votes
1answer
1k views
How to transform SoundWave Picture to sound?
I would like to recreate a sound from a picture of a soundwave.
But i see a lot of theorical question.
And im not sure its possible....
I mean, it is possible to create a sound...
But to make ...
0
votes
0answers
33 views
Sync on minimum/falling edge
I have a signal that I want to process (with Java) and so far I'm making good progress. However, the devil is in the details. For reference, it's a sound file at 48000Hz, 16-bit, I'll refer to samples ...
0
votes
1answer
211 views
Normalizing audio waveforms code implementation (Peak, RMS)
I have some audio data (array of floats) which I use to plot a simple
waveform.
When plotted, the waveform doesn't max out at the edges.
No problem - the data just needs to be normalized. I iterate ...
0
votes
0answers
55 views
Realtime detection of a simple sound
I was wondering if there are any simple tools I could use to detect a particular sound in realtime (and of course ultimately take some action after that).
This is a loop of the sound I want to ...
0
votes
1answer
640 views
Delay-and-sum beamforming: implementing steering in C
I am currently trying to understand how delay-and-sum beamforming works.
I have found this website which explains the process of this technique very well in which the following C code is provided:
<...
1
vote
1answer
34 views
Why does this video's audio change depending on the playing device?
Yesterday I noticed that if I played this video from my smartphone on speaker, one could barely hear anything. On the other hand, if I used earphones I could hear it perfectly.
Then, I tried with ...
1
vote
1answer
161 views
Harmonic Product Spectrum algorithm. I dont understand one step
I was looking some Harmonic Product Spectrum algorithm examples and I came up with this:
...
3
votes
2answers
496 views
Generating inaudible sound waves using MATLAB
I want to generate inaudible sound waves (above 18kHz) with 48kHz sampling rate using MATLAB.
Generating a sound wave with 18kHz frequency makes it inaudible.
I've inserted the data in the 18kHz ...
