These days, streaming services deliver decent audio quality straight to our phones and earbuds, but a DIY creator and YouTuber takes it a step further. Julius Curt or Julius Makes built a custom cassette-themed Bluetooth music player.
But instead of playing music directly, the player records audio from a tape loop in real time. Then it plays the music, giving you warm, nostalgic vibes with hints of lo-fi and subtle saturation.
The concept is clever, but simple. The music player receives audio from your phone via Bluetooth, converts it to an analog signal, mixes it to mono and sends it to the recording head of a modified cassette deck.
Then the visible ribbon rotates around 3D printed guides and passes a read head. The sound is then broadcast via a built-in speaker or headphones. This complex journey through the cassette deck and tape introduces some of the natural compression and imperfections that digital plugins have attempted to reproduce. Still, they can’t quite compete, given the analog nature of this music player.
However, creating an analog music streaming device was no easy feat. Older cassette decks have complex electrical designs, such as grounding the case to the positive power rail rather than ground, which can cause shorts when using Bluetooth modules.
Julius spent months debugging, testing custom isolation transformers and voltage regulators, before getting the analog streaming device working. He had to design five custom circuit boards in KiCad, as well as circuits to convert the stereo audio to mono, play the pre-bunched audio with an equalizer, and enable the autostart functionality for the Bluetooth module.
To make the device even more immersive, he added a light-up VU meter that turns off when the music reaches peaks.
The result is a Bluetooth analog cassette deck with Spotify streaming, housed in a stainless steel case with a transparent acrylic front for viewing the internal components. The visible ribbon loop guides the brown ribbon, just like your music player does. It also features large orange knobs for adjusting recording levels for distortion or adjusting the output volume.
Overall, this is an interesting DIY project, although a little more complex for some users due to the soldering required, even if one follows the instructions exactly. For those just looking to get a brand-new cassette player with basic equipment and features like USB-C charging instead, the FiiO CP13 is an easy, but expensive recommendation to make.
