why does the sound with different sampling frequency sounds the same ?

6 visualizaciones (últimos 30 días)
Dear people,
I am trying to write an audio with the following lines. However, every after I write an audio into a file and play it, they sound the same no matter what the sampling frequency is.
clear all
FrequencySampling = 2500; % 2500 for safe 10000 for shock
duration =17;
t = linspace(0, duration, FrequencySampling*duration+1); % Time Vector + 1 sample
t(end) = []; % remove extra sample
w = 2*pi*1000; % Radian Value To Create 1kHz Tone
for i=1:repeats
s = sin(w*t);
pause(5) %ITI 60 sec
Please recommend me any possible reasons or let me know if I have done sth wrong.

Respuesta aceptada

Akira Agata
Akira Agata el 7 de Jul. de 2020
That's the basic of the 'Sampling theorem'. As long as frequency component of the signal is less than Nyquist frequency ( = sampling frequency * 0.5), the original signal can be re-generated.
Looking at your code, the signal frequency is 1 [kHz] and both sampling frequencies (2.5 [kHz] and 10 [kHz]) satisfy the Nyquist condition. So the regeneratd signal sounds the same.
  2 comentarios
Yanjika O
Yanjika O el 7 de Jul. de 2020
Then, how to make them different in terms of sampling frequency (2.5kHz and 10kHz)?
Akira Agata
Akira Agata el 7 de Jul. de 2020
Then you need to compare one re-generated signal with sufficient sampling frequency (= satisfies Nyquist condition) and another signal with insufficient sampling frequency.
The following is an example. (please compare the two .wav files with different sampling frequency)
load handel.mat
% Sufficient sampling frequency (8192 [Hz])
% Insufficient sampling frequency (4096 [Hz])

Iniciar sesión para comentar.

Más respuestas (0)


Más información sobre Audio I/O and Waveform Generation en Help Center y File Exchange.


Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by