audio.ninja

Table of Contents

1. Introduction
2. Materials Needed
3. 3D Print
4. Pin Configuration
5. Compatible Walkmans

1. Introduction

This project documents how to build a custom Joint Text cable that allows compatible Sony CD players and MiniDisc recorders to automatically transfer CD-TEXT track titles during recording. By recreating the functionality of Sony's rare RK-TXT1 cable, you can restore or replicate this convenient feature using 3D printing, easily sourced connectors and basic wiring.

Once built, you can test the cable by connecting a Joint Text-compatible CD player to a supported MiniDisc recorder, and verify that track names appear automatically as the MD is recorded.

Disclaimer: This project involves building and using custom cables and 3D-printed connectors. Misuse, incorrect wiring, or carelessness may result in damage to your equipment. Always verify the wiring layout, inspect physical connections, and ensure the 3D-printed connector fits properly without forcing it into the device. Test on secondary or non-critical units whenever possible, and proceed with caution.

This project is independent and not affiliated with, endorsed by, or sponsored by any brand or company mentioned.

You are welcome to build, test, and enjoy your own custom Joint Text cable using the information provided here. However, reselling cables or products made using this information is not permitted.

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2. Materials Needed

- Soldering kit

- Heat shrink tubing

- Wire

Any cable with three conductors, or two conductors plus a shield or ground wire, of reasonable length should work well.

- 3D Printer and Filaments

A 0.4mm nozzle and PETG filament are used.

- 2.54mm Pitch Board-to-Board Connectors

Easy to source and reasonably strong. The model uses 0.64mm x 0.64mm pins, so you can pull the pins out and use them as needed.

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3. 3D Print

The models are available for download here.

The ZIP file includes two sets: STL and 3MF. The STL files were generated from the 3MF model, but the shallow notches designed to park the pins inside the unit's connector are missing. This should not cause any issues.

PETG is recommended, as you don't want the part to break off inside your Walkman. Each pair takes about 10 minutes to print, be sure to test the strength before use.

Depending on the printer and filament used, the connector's size and the pin holes may vary slightly. Please adjust as needed for a proper fit.

If the holes are too tight, you may need to press the pins in firmly a few times to open them up. If they are too loose, consider applying a small amount of glue to secure the pins in place.

The models are designed with the minimal size needed to reduce strain. On the mini jack side, there's only enough clearance for the original MDR-E838 plug, larger plugs may not fit properly. There's a small protrusion on the opposite side: if the plug blocks the audio jack, it's upside down.

The connector should plug in and out without difficulty. However, since the mini jack part is missing, it won't stay firmly inside the connector and may pop out unintentionally. I do not recommend enlarging the model, as this might damage the ports on the Walkmans. Careful positioning should prevent most issues.

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4. Pin Configuration

The connector on the MD side has only the essential pins exposed. The pin configuration is as follows:

Original pinout source: Link

Once finished, it should look like this:

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5. Compatible Walkmans

MD

CD

This list is compiled from manuals found online and may not be fully accurate.
It seems only D-EJ1000 / D-EJ955 support CD-RW.

Some compatible CD players may support Joint Text even if they don't advertise or display CD-TEXT functionality themselves. Conversely, many later CD players that support CD-TEXT display are not equipped with Joint Text output.

The term "MD Link" seen in some catalogs refers to TOSLink optical digital audio, not Joint Text functionality.

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Last update: 2025-07-04