This Affordable DIY Device Lets You Record Directly From an S/PDIF TOSLINK Optical Connection

In the world of hi-fi audio, you want to eliminate analog-to-digital and digital-to-analog conversions as much as possible. Ideally, you only record through a single high-quality ADC (analog-to-digital converter) and only listen through a single DAC (digital-to-analog converter). An S/PDIF TOSLINK optical interface helps, as it allows for digital transfer at up to 24-bit/192kHz for uncompressed stereo PCM. If you want to record that output, this affordable DIY device designed by Elehobica is perfect.

Why would you want to record from a TOSLINK connection? It is fairly niche, but this will let you easily and conveniently record from any audio source connected to, say, a stereo receiver with a TOSLINK output, without any loss to compression — or from any media player that has a TOSLINK output.

Maybe you’re into an obscure format like MiniDisc, for example. If you have a MiniDisc player with TOSLINK output, you can record the audio stored on any MiniDisc. And if you are into analog media, like vinyl records, you can record with the benefit of your stereo receiver’s high-end ADC.

The device itself is simple and doesn’t cost much to build. It consists of a custom PCB hosting a Raspberry Pi Pico or Pico 2, a TOSLINK port, an SD card slot, a couple of buttons, and a switch. The switch lets you select either 16-bit or 24-bit recording. The buttons let you start/stop recording and reset the system.

To use it, you simply pop in an SD card, connect the TOSLINK cable, and start recording. When you’re done, you can copy the file from the SD card to your computer. That’s a standard WAV file, so compatibility shouldn’t be an issue.

Elehobica programmed some nifty features to help, like smart auto-splitter and blank detection. With WiFi connected, it will even timestamp recordings.

So if you want to record from a TOSLINK source, this is a great way to do it.