You may check this other anser related to import data:
https://www.mathworks.com/matlabcentral/answers/460098-import-text-data-as-a-numeric-matrix-with-specific-delimiters
Also, I am attaching a code you might use:
%% Initialize variables.
filename = 'sound.txt';
delimiter = '\t';
startRow = 2;
%% Format for each line of text:
% For more information, see the TEXTSCAN documentation.
formatSpec = '%*s%f%f%f%f%f%f%f%f%[^\n\r]';
%% Open the text file.
fileID = fopen(filename,'r');
%% Read columns of data according to the format.
dataArray = textscan(fileID, formatSpec, 'Delimiter', delimiter, 'TextType', 'string', 'HeaderLines' ,startRow-1, 'ReturnOnError', false, 'EndOfLine', '\r\n');
%% Close the text file.
fclose(fileID);
%% Create output variable
sound = [dataArray{1:end-1}];
%% Clear temporary variables
clearvars filename delimiter startRow formatSpec fileID dataArray ans;
[X,Y] = meshgrid(-10:5:25, -15:5:100);
surf(X,Y,sound)
xlabel('X');
ylabel('Y');
zlabel('Sound');
