My entire life I have known speach to mean the verb that describes the act of speaking in the present tense, while speech to be the verb that is the past tense act of speaking professionally/publicly to a group.
According to google :The correct spelling is speech. “Speach” is an outdated spelling from hundreds of years ago and is now considered a spelling mistake.
I would pronounce that like the sound an old man would make when he’s clearing his throat. Perhaps before he gives a speech.