problem installing debian

[jaffar at ecstatico.net]

Hi Folks.  I cannot tell at which point of the boot process do i need to enter the command to activate my speech synth to begin the install process.
Well, i reboot my pc, then insert the debian netinst disk that i have made from the iso image.  The pc speaker beeps, then there's a whole lot of activity, and then the disk spins for about a minute and stops.  I would have thought that tha'ts the point at which i would type the speech install command, so i type
install speakup.synth=dectlk which is my external synth, then press enter.  The disk spins again, but no speech.  When it stops and i press the enter key again, the disk spins again, but with no speech guidance whatsoever.  So, at which point of the boot process do i issue the install with speech command?  Cheers!