Hi, all!
Bei audible.de (aber vielleicht nicht bei audible.com) gibt es einige “John Sinclair Classics” gratis zum Anhören.
Zum Beispiel Teil 1: “Der Anfang”
Von der Qualität des Horrors kommt das zwar nicht an einen
Stephen King heran, aber es ist dennoch unterhaltsam (in einem nostalgischen Pulp-Sinne).
Abgesehen davon ist das jedoch eine professionelle Hörspiel-Produktion!
Gute Unterhaltung
Peter
“Gute Unterhaltung” <— I see what you did there. 
Some, much later, episodes are available for purchase on Audible.com. But it might be worth the effort to create an Audible.de account.
Another place with lots of early/classic Hörspiels is Spotify.
Not free, but I can strongly recommend the series‘ by Ivar Leon Menger: Monster 1983 and Ghostbox.
““Gute Unterhaltung” <— I see what you did there. ;-)”
Ich plädiere auf “unschuldig” im Nicht-Sinne der Anklage 
How does Deepl translate that nice little German sentence?
“I plead not guilty to the charge of not guilty to the charges”
<it’s absurd but I like it :-)>
“But it might be worth the effort to create an Audible.de account.”
Definitely. Audible.de offers a lot of stuff in German or English for free
(e.g., in the case of “John Sinclair,” the first ten episodes in German are free
By the way, you can also find many of the “John Sinclair Hörspiele” on Youtube for free, e.g. on this YT channel: John Sinclair - YouTube
Personally, I rarely listen to this stuff (e.g. “John Sinclair”, “Perry Rhodan”, Karl May’s “Winnetou”, etc.) anymore because nowadays I prefer non-German audio productions with more advanced / mature topics, esp. for language learning.
However, for people who are learning German and are interested in such popular/pulp genres, it can be very entertaining as the audio productions
are often of high quality.
“Another place with lots of early/classic Hörspiels is Spotify.”
I agree.
And I think we already published a list of German radio broadcasters (i.e. Deutsche Hörfunkanstalten wie der WDR, MDR, Bayern 2, etc.) on LingQ, which offer thousands of audio books / audio dramas for free.
WDR, for example, also offers “Tatort” as an interactive audio game: https://www1.wdr.de/radio/hoerspiel/index.html
Switching back to German:
Was freie Hörspielproduktionen angeht, ist der deutschsprachige Raum (Deutschland - Austria - Schweiz) definitiv ein Paradies, insbesondere für diejenigen, die Deutsch lernen (möchten).
Nice Sunday to y’all
Peter
I know, I’m answering quite late to your post, but I stumbled upon it just today.
Monster 1983 and Ghostbox are really amazing audio plays. I can strongly recommend them. The only disadvantage for learners is that there is no transcript available.
Wow Hallo Vera,
Wie geht’s?
It’s been many years since you’ve been active here on the forum.
I hope you are well! I would love to hear from you privately if you get the chance write on my wall