Pre-roll ads are 15-30 seconds of ads at the start of a podcast and are placed before or after the host introduces the show. Pre-roll ads are a bit more formal than other ads and usually feel like ads. Mid-roll ads are 60-90 seconds ads that usually appear in the middle of an episode. Like commercials on TV and radio shows, the host pauses the show and talks about the product.
But in this case, instead ghost mannequin effect of the marketer promoting the product, the host promotes it. Mid-roll ads feel the most native, but they're also the most expensive of all ads. Post-roll ads are 20-30 seconds of ads that appear at the end of your podcast. Directing listeners to the CTA is especially effective, as post-roll ads will be displayed at the end of the show.
Listeners will continue to attend the show, but you don't have to keep that in mind when the show ends. They are more likely to accept visiting websites and remembering promotional codes. "Live lead" ads are ads that naturally fit into the flow of podcasts. Organizers will promote the product live at the show during the "Commercial Break" and then pick up the show.