How to create a Stereo Sweep from Frequency A to B in a given time?
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I would like to create an audio sweep from frequency A to B in a given time:
For example from 400 to 600 Hertz in 1 second.
Or is it even possible to create an audio sweep from A to B in a given time and then hold this frequency for a given time?
For example from 400 to 600 Hertz in 1 second and the hold 600 Hertz for 9 seconds
Thank you for helping it is much appreciated!
Star Strider on 6 Dec 2021
The built-in Signal Processing Toolbox chirp function is perfect for this —
Fs = 1E+4;
t1 = linspace(0, Fs-1, Fs)/Fs;
s1 = chirp(t1,400,t1(end),600,'linear'); % Linearly-Increasing Signal
t2 = linspace(t1(end), 9*Fs-1, 9*Fs)/Fs;
s2 = cos(2*pi*600*t2); % Conmstant Signal
t = [t1 t2]; % Concatenate
s = [s1 s2]; % Concatenate
[sp,fp,tp] = pspectrum(s,Fs,'spectrogram','TimeResolution',0.05); % Display Results
To actualy llisten to it —
player = audioplayer(s, Fs);
More Answers (1)
Jon on 6 Dec 2021
As an alternative, if you don't have the signal processing toolbox, or for some reason preferred to see the details you could do it like this:
% define time and frequency breakpoints
tb = [0 1 9]
fb = [400 600 600]
% compute swept frequency
tFinal = max(tb)
fSample = 10000; % sampling frequency
t = linspace(0,tFinal,fSample*tFinal);
f = interp1(tb,fb,t); % linearly interpolate frequencies to get sweep
% compute output
y = sin(f*2*pi.*t);
% plot result