Magnetophon is a cassette player without the transport mechanism — a mono cassette head in the panel and a NAB equalised amplifier circuit, this is a tool for experiments with tape.
Music Thing Modular's Magnetophon (musicthing.co.uk/pages/magnetophon.html) has been generously released as open hardware and these PCBs have been manufactured directly from the files provided (note, the is the old design, not the black and gold one on the link).
The module comes with a mono cassette head mounted directly in the panel but, more conveniently, there's a plug-in 'wand'. Stick some tape on some card or board and rub the head over it to playback at variable speed. For best results use mono cassettes (check eBay for cheap, old language tapes, or scour Discogs specifically for mono releases).
You should also be able to mount the head with giant loops strung up in corridors and stuff (get in touch if you want extra long wands).
Includes unlimited streaming of Magnetophon Demo
via the free Bandcamp app, plus high-quality download in MP3, FLAC and more.
Dragging tape directly across the panel-mounted play head, I'm also processing the sound through a DIY Karaoke Delay module.