Why is the proprietary 4.4mm connector of portable SONY players not grounded? A standard balanced headphone cable only has four connection points - R+, R-, L+, and L-. It does not include a grounding point on the 4.4mm plug. On the other hand, if the 4.4mm headphone connector were grounded, negative feedback could occur during connection and disconnection. Perhaps for this reason, the SONY 4.4mm connector is not grounded.
Why does sound quality improve after grounding? A necessary condition is that the used 4.4mm headphone cable should be shielded and properly grounded. The casing of Sony players, specifically NW-WM1Z and NW-WM1ZM2, is made of highly pure and highly conductive oxygen-free copper with gold plating, which can provide good grounding for shielded cables. When connecting a shielded cable with a 4.4mm plug, the cable's protective layer is then grounded to the player's chassis. As a result, it can better prevent the effects of external electrostatic and electromagnetic interferences.
The built-in grounding enhances the reliability and safety of SONY player chassis connected to the grounded 3.5mm connector. The grounding plug DJ44S used is much shorter than the 3.5mm headphone plug, which ensures proper grounding and prevents connector damage from unbalanced force. Unbalanced force refers to the pressure point being excessively shifted in one direction when inserting or removing the plug at an inclined angle. Since the 3.5mm headphone connector typically uses a plastic casing, this can lead to connector damage.
Features:
- Designed for NW-WM1ZM2 / WM1AM2
- Material: Aluminum 6063
- Internal wiring: 25.5AWG 6N OCC
- Contact group: Gold-plated copper
- Weight: 38 g
Package Includes:
- Adapter for SONY NW-WM1AM2 / WM1ZM2