Wikipedia talk:WikiProject Spoken Wikipedia/Recording guidelines/Sample configurations/Archive 1

Not the hot setup

 
sound travels through the vocalization tube, and causes the embossing arm to create dents corresponding to the sound

TAEdison Using tinfoil sheet wrapped around a grooved cylinder, embossed by an up-and-down motion of the embossing arm in response to the sound wave pressure exerted by speaking into the vocalisation tube. Extraneous sound is limited by virtue of it not being directly in front of the speaking tube. TAEdison