thx paul and sterretje,
yes 21 is a pin number, used with tone() function to emit the noise in buzzer.
with setup - voice.say(spah); const spah should be linked
and the buzzer should be activated in loop;
- which seems not happening.
as per suggestion had a look in talkie library.
and a hint was -
""Talkie sets up a special very high speed PWM, so audio can be taken directly from pin 3 with no other filtering"". tried pin 3 instead of 21 - no luck.
maybe buzzer cannot be used with talkie.