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%DEMO_ABSOLUTETHRESHOLD Standards for absolute threshold of hearing
%
% This demos generates a simple figure that shows the behaviour of
% the different standards for absolute thresholds of hearing.
%
% Figure 1: Thresholds of hearing by standard
%
% The figure shows the behaviour of the different absolute thresholds of
% hearing.
%
% Figure 2: High frequencies
%
% Absolute thesholds for the ER2A and the Sennheiser HDA-200
% earphones are provided up to 16 kHz.
%
% See also: absolutethreshold
%
% Url: http://amtoolbox.sourceforge.net/amt-0.10.0/doc/demos/demo_absolutethreshold.php
% Copyright (C) 2009-2020 Piotr Majdak and the AMT team.
% This file is part of Auditory Modeling Toolbox (AMT) version 0.10.0
%
% This program is free software: you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
%
% This program is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
% GNU General Public License for more details.
%
% You should have received a copy of the GNU General Public License
% along with this program. If not, see <http://www.gnu.org/licenses/>.
amt_disp(['Type "help demo_absolutethreshold" to see a description of how this ', ...
'demo works.']);
figure(1);
flow=125;
fhigh=8000;
plotpoints=30;
xrange=linspace(flow,fhigh,plotpoints);
types = {'iso226_2003','map','er3a','er2a','hda200'};
legends = {'THR (free field)','MAP (free-field)','THR (ER-3A)','THR (ER-2A)','THR (HDA 200)'};
symbols = {'r-' ,'k-' ,'g:' ,'b-.','y--' };
lines = {2 , 1 , 2 , 2 , 2 };
ticks = [125,250,500,1000,2000,4000,8000];
hold all;
for ii=1:numel(types)
semiaudplot(xrange,absolutethreshold(xrange,types{ii}),...
'tick', ticks,...
'opts',{symbols{ii},'Linewidth',lines{ii}});
end;
legend(legends{:},'Location','North');
xlabel('Frequency (Hz)');
ylabel('Absolte threshold (dB SPL)');
xlim([2 35]);
figure(2);
flow=125;
fhigh=16000;
plotpoints=30;
xrange=linspace(flow,fhigh,plotpoints);
types = {'er2a','hda200','iso226_2003','map','er3a','er2a','hda200'};
% legends = {'er2a','hda200'};
symbols = {'b+','y*','k' ,'r--' ,'g' ,'b:','y'};
hold all;
for ii=1:2
semiaudplot(xrange,absolutethreshold(xrange,types{ii}),...
'tick', ticks,...
'opts',{symbols{ii},'Linewidth',lines{ii}});
end;
hold off;
% legend(legends{:},'Location','North');
% xlabel('Frequency (Hz)');
% ylabel('Absolte threshold (dB SPL)');
% xlim([2 41]);
% types = {'iso226_2003','map','er3a','er2a','hda200'};
% symbols = {'k' ,'r--' ,'g' ,'b:','y' };
fc=125:125:8000; hold on; box on;
for ii=3:numel(types), opt={symbols{ii}, 'LineWidth', 3};
semiaudplot(fc,absolutethreshold(fc,types{ii}),'opts',opt);
end;
% legend(types);
legend(types,'Location','North');
xlabel('Frequency (Hz)');
ylabel('Absolute hearing threshold (dB re 20 µPa)');