Audio in email is not a podcast

Today Substack announced support for sending audio episodes in email newsletters:

Subscription podcasting through Substack works in the same way as publishing newsletters. Once the feature is enabled, you can create an audio post that is just like a normal post and can go out to everyone or only to subscribers. After receiving the post by email or accessing it on the web, subscribers can listen to the audio through the Substack web player.

This looks like a great feature for Substack customers, but it’s not a podcast. As the podcasting industry grows, with everyone trying to monetize podcasts or build new businesses around podcasting, it’s really important that we keep using the right words to describe it. A podcast has to have a feed so that it’s available in podcast players like Overcast, Castro, and Apple Podcasts.

Michael Zornek said it well earlier this week after Spotify acquired Gimlet and Anchor:

It is not a podcast unless there is a RSS feed.

I’m not splitting hairs about this. If we accept calling “any audio on the internet” a “podcast”, we undermine what makes a podcast unique: not just the convenience of delivering audio directly to your device, but the openness that ensures that podcasts work in a variety of players, without a single company with too much control trying to lock down the format.

Luckily, I think the Substack folks probably know this. In their announcement post, they also added:

We may soon add the ability to add a private feed of episodes to podcast players, but we like the web solution for now. (Give us your feedback, etc.)

Here’s my feedback: please don’t call it a podcast until you have the feed ready, whether it’s a private feed or public. When we added audio uploads to, we had full podcast feeds and everything was available from your own domain name. The web will be better if we encourage the same support of open formats in all new platforms.

Manton Reece @manton