# Questions tagged [amplitude]

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### How do I calculate peak amplitude of the signal components after zero padding and FFT?

I am learning about DFT and trying to apply it to some audio processing. I am new to DSP but experienced in programming and have some background in math and physics. The FFT algorithm I use (lomontFFT)...
179 views

### How to convert multi-band Energy Time Curve (ETC) to Impulse Response (IR)?

I am running my own sound simulator. Now I have obtained the Energy Time Curve (ETC, expressed by energy) by physical simulation, and they are stored in 8 discrete frequency bands (because decay of ...
110 views

### (Newbie question) Calculation DC-offset and RMS

Being a newbie on this topic I beg you to be indulgent to me if my questions should be kind of "too" simple ;-) For doing automatic analysis on my audio material I started calculating the ...
92 views

### How to generate the amplitude of a signal with a certain power spectral density?

I am a newbie. If I posted a question someone else already asked, please forgive me. Thank you! Now, I have a power spectral density named $P(f)$ as a function of $f$. Let's say this function is ...
84 views

### Values (amplitudes) of the CWT and their relationship to waveform amplitudes?

I'm coding up a scalogram in C++. Right now it calculates a single row of the CWT matrix and immediately maps it to a line of pixels. Trouble is my colouring scales with the values of the transform ...
74 views

### ssbmod single sideband modulation artifacts

clc; clear all; close all; [c,fs]=audioread('60hz.wav') r=ssbmod(c,160, fs) r=r/max(max(abs(r))) audiowrite('artifacts.wav',r,fs,'BitsPerSample',24) I am trying ...
62 views

### amplitude at exact frequency in wide band signal

Could anyone suggest the most computationaly efficient method for finding amplitude of exact frequency having a noisy wide band signal. To be more specific about a task. I have some physical ...
225 views

### How do I find amplitude modulation effects in natural signals

It is relatively easy to discover overlaid (additive) signals in natural phenomena using wavelet decomposition, Fourier Transforms, CEEMD, etc, because addition in the time domain is the same as ...
36 views

### Extract amplitude values from a wav file

I would like to extract the amplitude value from a wav file. Using Python I can extract the raw data into an array. How do I go about extracting the amplitude value of each sample?
39 views

### Emulating tape distortion of low-level audio signals

I'm working on a tape echo emulation in Reaktor, and I've based the frequency response, tape speed warble, high-amplitude saturation and tape hiss on a paper I found about the Roland Space Echo. ...
45 views

### Amplitude decrease in FFT at higher frequency for multisine

I am adding sine signals with different frequencies but same amplitude=100. Sampling frequency is 50MHz. I am not getting 100 in frequency domain for frequency 787KHz. At 1K, 3K I am getting 100 ...
31 views

### 1D amplitude spectrum with MATLAB

I have written the following code to calculate the amplitude spectrum of a test signal. ...
153 views

### What is the x and y axis showing for this matplotlib.pyplot histogram of a .wav file?

The python code below generates a histogram from a .wav file, but what exactly does the histogram show? Is the x axis amplitude binned by sampling rate? Is the y axis a count of how many samples are ...
87 views

### Instantaneous amplitude of a constant frequency sine wave?

I am playing around with the Hilbert transform using Python's scipy.signal.hilbert package to better understand what the various instantaneous properties are given different input signals. One input ...
53 views

### Discussion of simulation results of a signal sequence: amplitude

I need your help in understanding if the simulation result is correct. I have simulated a random BPSK sequence that was upsampled and filtered with a raised cosine filter. The length of the filter is ...
248 views

### RMS of signal vs average amplitude

I am trying to estimate the average amplitude of some signal with frequency 6 Hz, sampled at ~300 Hz. See figures for a part of the signal and its dft calculated using matlab. I estimate the average ...
28 views

### modulation depth

When a value for the power dissipated by an AM signal is given, and the depth of modulation is also given. Then you are told to find the modulation depth required to increase the power to a higher ...
70 views

### Is there a way to break down a signal into its respective phases (4 in this case) to be later analysed individually

Is there a way to extract amplitude information but over 4 phases of the same frequency. That is, if the frequency is known could I extract amplitude peaks (between given values)in the time domain in ...
66 views

### frequency amplitude asymmetry

I want to calculate the frequency amplitude asymmetry between two signals, EEG signals in particular. As a result, I expect a value ranging from 0 to 1. I have some references regarding that, but it's ...
234 views

### How accurate is Python's FFT?

I am getting started with Python's FFT. I tested it on a signal that is a sum of three signals, two of which have an eigenfrequency of the grid, the third one does not (but due to large no. of data ...
166 views

### Is there a way to filter out low volume content in an audio sample?

Imagine you are listening to a digital file that contains some random speech. Now, while you are listening to it, you also hear in the background (spatially) some low volume content, either noise, ...
373 views

### FFT amplitude vs IQ amplitude

I'm very new to digital signal processing, so please let me know if my question doesn't make sense. I calculated the amplitudes (using the formula : $10 \log_{10}(i^2 + q^2)$) for some IQ data ...
105 views

### When to use raw signal strength, vs. when to filter first

I am collecting I/Q samples from an RTL SDR dongle. I notice the rtl_power utility provided for Linux filters and does other processing, before reporting signal ...
835 views

### How to show the time history of a signal down-sampled ? under the rate of 25Hz & 40Hz and find its DFT analysis?

How to show the time history of a signal down-sampled under the rates of 25Hz & 40Hz and find its DFT analysis using Matlab ? The sample signal is in a data file (sensor_data.mat) its sampling ...
69 views

### How to scale fundamental frequency to [0,1]?

[Sorry for the noobish question...] I have a signal which is known to be generated by a process operating at some known rate $f$ Hz and the sampling rate is also know to be $K$ Hz. Now I do a ...
44 views

### Amplitudes and phases of transform of an image

I have recorded an image of a large macromolecule and after several types of image analysis, have obtained a rotationally averaged image, that is not quite perfect, but appears to show 6-fold symmetry....
83 views

### Phase difference betwen 2 signals, 1 signal with unknown function

I understand this question may have been addressed however I have a major difference. I started out with a sinusoid of form A*sin(2 pi freq t + phase) and I know ...