How to get partial data from audiorecorder

Hi.

I want to plot my speech in realtime. now i using this code

   clc; clear all; close all;
  fs=14000;
  l=10;

recObj = audiorecorder(fs,16,1,1); 
%recObj.UserData=1;
recObj.TimerFcn = {@my_callback_fcn};

disp('Start speaking.')
recordblocking(recObj, l);
disp('End of Recording.');

y = getaudiodata(recObj);

play(recObj);
x=0:1/fs:l-1/fs;
plot(x,y);

and callback function

function my_callback_fcn(obj,event)
   y = getaudiodata(obj);
   plot(y);
   hold on;
   obj.UserData=obj.TotalSamples;
end

In this case my script begins to lag after 3-4 secs of work. How can i solve that problem? I tried to find find some fields in

recobj

that contain original data, but seems like it doesnt. So how can i atleast get partial data from recObj(planing to use plot and hold on)?

Answer 1

[Walter Roberson]

audiorecorder is not designed for real-time work. You should look at the DSP System Toolbox, which has ability to use ASIO drivers for low-latency work.

[Derrick Ling]

Is this answer still valid? from this website, it states audio system toolbox is capable of doing real-time signal processing

[Walter Roberson]

That toolbox did not exist at the time that answer was written. Probably you could use either toolbox now