doubt regarding sampling frequencies
The soundsc command will playback $f_s$ samples per second. Playing back at a faster rate than you recorded will increase the pitch of the speech. Playing back at a lower sample rate will reduce the pitch. 

If you prefer to think in the frequency domain; all the information is scaled on the frequency axis with relation to the change in $f_s$. Reducing fs squashes the information on the frequency axis and increasing $f_s$ will stretch the information on the frequency axis.