How do I read and split an audio file into four different frequency ranges?

S
sangeet sagar · Mar 9, 2024 · 1.9K views
Question
I have an audio file of sampling frequency as 16 kHz. Now I would like to read it and split its samples into four range. Namely:   0 kHz - 1 kHz 1 kHz - 2 kHz 2 kHz - 4 kHz 4 kHz - 8 kHz I have come about the following code but I am not sure if it is correct? I wanted to know if there is any other way. [signal,fs]=audioread('003.wav'); SigFD = (signal); n = length(signal); % number of samples deltaF = fs/n; % frequency resolution F = [0:floor(n/2)-1, -(floor(n/2)):-1]*deltaF; % frequency vector lowF = 0; % lowF and highF defines one of the range highF = 1000; part1Range = abs(F)>lowF&abs(F)
Expert Answer
Profile picture of John Michell
John Michell PhD Expert
Answered Aug 26, 2026
If you have R2018a or later, use the bandpass (link) function on your original signal, each with different passband limits.
 
If you have an earlier version, use ellipord (link) and ellip (link), that together are almost as easy.
 
 
The first filter is a simple lowpass filter with a passband a 1 kHz. You can use this prototype code to design it.
 
This designs the second filter:
 
 
Fs = 1.6E+4;                                                % Sampling Frequency (Hz)
Fn = Fs/2;                                                  % Nyquist Frequency (Hz)
Fnotch = 1.5E3;                                             % Notch Frequency (Hz)
BW = 1E+3;                                                  % Passband Width (Hz)
Ws = [Fnotch-BW/2-1 Fnotch+BW/2+1]/Fn;                      % Passband Frequency Vector (Normalised)
Wp = [Fnotch-BW/2-5 Fnotch+BW/2+5]/Fn;                      % Stopband Frequency Vector (Normalised)
Rp =   1;                                                   % Passband Ripple (dB)
Rs = 150;                                                   % Stopband Attenuation (dB)
[n,Wp] = ellipord(Wp,Ws,Rp,Rs);                             % Default Here Is A Bandpass Filter
[z,p,k] = ellip(n,Rp,Rs,Wp);
[sos,g] = zp2sos(z,p,k);                                    % Use Second-Order-Section Implementation For Stability
% s_filtered = filtfilt(sos,g,s);                             % Filter Signal (Here: ‘s’)

figure
freqz(sos, 2^14, Fs)                                        % Bode Plot Of Filter
set(subplot(2,1,1), 'XLim',[0 Fn])                          % Optional, Change Limits As Necessary For Best Resolution
set(subplot(2,1,2), 'XLim',[0 Fn])                          % Optional, Change Limits As Necessary For Best Resolution

The others are the same except for the centre frequencies and the bandwidths.

 

100% Run Guarantee 3-Hour Fast-Track Delivery

Need a Custom Version or Complete Simulation for This Problem?

Our 500+ PhD engineers build, debug, and optimize working MATLAB scripts and Simulink (.slx) models tailored to your exact assignment rubrics with zero plagiarism.

Tested on MATLAB R2024b / R2026a
Turnitin 0% Plagiarism Report
Free 7-Day Revisions Guarantee
Have a different question? Ask here

Get a Free Consultation or a Sample Assignment Review!