Cassette Streamer Lets You Stream Music Through Real Tape

Julius Makes, a YouTube creator of some fairly weird electronics projects, recently attempted to build something that combines old-school cassette playback with ultra-modern streaming technology. He calls it the Cassette Streamer, and it has all the hallmarks of a vintage portable cassette player, including knobs, buttons, and a large clear front panel that allows you to view the tape as it moves by.

Stick a cassette in, pair your phone with the device via Bluetooth, and then start a playlist; the audio comes in, is transformed into something the ancient cassette deck can comprehend, and is recorded onto the tape in real time. A few seconds later, the deck reads over what was previously recorded and delivers the signal to an internal speaker, resulting in a natural echo effect, while the tape adds a lot of lo-fi distortion, wobble, and compression to the sound.

So Julius began with the’meat’ of the old cassette player, but expanded the tape’s path so that it sticks out beyond the cassette casing, guiding it with some brilliantly colored 3D printed parts. The way the brown tape slides past the heads and rollers transforms the mechanism into something reminiscent of a piece of art.

The electronics are handled by some custom boards, which just take the audio stream from the phone, reduce the stereo to mono, and send it to the record head on an old cassette deck via an auxiliary input. When it’s time to play it back, the signal is routed through a pre-amp to remove all of the weird stuff that happens when you record sound to tape, and then it’s divided out to a speaker amp and a few other outputs.

One of the most noticeable features on the front is an old fluorescent tube from a scanner that has been reused as a VU meter. Then you have some analog circuits that take the playback signal and amplify the parts that go over the line, driving the tube to light up when it’s loud and dim down when it’s quiet, resulting in a wonderful light show that moves in time with the music. The plus here is that it ensures the tube lasts much longer.

You have two knobs: one for controlling the recording level, so you can have a clean sound or a good amount of distortion on top of it, and another for increasing the volume on the internal speaker. The device also has quarter-inch jacks on the side, allowing you to use it as a standalone tape delay pedal for guitars or any other instrument you play.

Putting it all together was a bit of a job, so Julius had to be very accurate with all of the different approaches required, which is why he used a software application called KiCad to design the boards and then had them manufactured properly. He also 3D printed the components that hold everything together, lasercut the transparent panel, and commissioned a custom stainless steel enclosure to ensure durability and prevent overheating. On top of that, he added some bespoke knobs to give things a more tactile feel.
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