ADC 220X (1970–1974)

Name: ADC 220X
Brand: ADC

The ADC 220X is an induced-magnet phono cartridge from Audio Dynamics Corporation. It belongs to the company's X-Series, which also included the 25, 26, 550 XE, and 990 XE. The X-Series shared a basic design, and the models differed only in the grade of stylus assembly. The 220X sat near the entry level of the range.

The cartridge showed up in the period hi-fi press. High Fidelity (December 1970, p.1) listed the 220X among its lab test reports that month. Production is sometimes cited as 1972-1974, though the magazine coverage suggests the model was already on the market by late 1970.

Two variants were offered. The standard 220X has a 0.7 mil conical stylus. The 220X/E has a 0.3 × 0.7 mil elliptical stylus. Original pricing was approximately ¥6,800 in Japan (¥8,300 for the /E version) and about 68 Deutsche Mark in Germany.

Known specifications:

Frequency response: 10 Hz – 18 kHz ±3 dB
Output: 6 mV (at 5.5 cm/sec)
Channel separation: 20 dB (50 Hz – 10 kHz)
Compliance: 20 × 10⁻⁶ cm/dyne
Tracking angle: 15°
Recommended load impedance: 47 kΩ
Tracking force: 1 – 2.5 g
Stylus: 0.7 mil conical (R-20X) / 0.3 × 0.7 mil elliptical (R-20X/E)
Weight: 8 g

Little else is documented. No dimensions, distortion figures, or detailed design notes have turned up in the sources reviewed. The cartridge appears occasionally on the secondhand market, and a recent listing shows one offered at 26 EUR.