Technics SL-J1

The SL-J1 was a turntable and one in a series of linear tracking turntables consisting of SL-J2 and SL-J3 manufactured by the Technics Corporation of Japan. The SL-J2 and SL-J3 had the quartz Direct Drive (DD) system, whilst the SL-J1 was belt driven. All of these turntables used the gimbal suspension linear tracking tonearm, which moves across the record in a straight line similar to the cutting lathe that produced the original master record. An advantage of this is that it eliminates tracking error and thereby distortion. In this design, a DC motor controls the movement of the gimbal suspension tonearm, and a microprocessor system that receives data from an optoelectronic sensor controls the motor. These turntables use the standard "P-Mount" plug-in cartridge connector system adopted by many cartridge manufacturers. This allows the use of a wide range of cartridges such as EPC-P205CMK4, EPC-P310MC2, EPC-P550, EPC-P540, and EPC-P530. However, for the factory-installed cartridge, the replacement stylus was usually EPS-30CS.

Review

The SL-J1 uses leading-edge electronic engineering of that era. For the microcomputer, they use the MN1420 (IC301), which performs all the housekeeping functions. These were in the category of general-purpose 4-bit single-chip microcomputers, with 1 Kbyte ROM memory space, that they produced using NMOS technology. For the tonearm motor drive and blank groove detection circuit, they use a dedicated integrated circuit AN6690 (IC401).

The main difference between the belt-driven SL-J1 and the quartz-phase-locked DD SL-J2 and SL-J3 is in the wow-and-flutter figures. They rate the former at 0.045 % wrms, whilst the latter two are rated at 0.025 % wrms. However, a good working SL-J1 with a good motor and drive belt should perform just as well and many people should not be able to tell the difference. Although it is a basic specification turntable, you still get powerful functions such as:

• Automatic speed selection
• Automatic disc size selection
• Skip
• Direct access
• Auto lead-in
• 2-speed search
• Automatic return
• Automatic stop
• Repeat

Cost/eBay

Turntables manufactured by the Japanese Matsushita Corporation tend to be very reliable, and consequently, they are one of the most popular in second-hand markets. With the SL-J1, SL-J2, and SL-J3, you get the luxury provided by automation, and the benefits of DD quartz servo system, which adds to the production of high quality audio. Whilst a broken turntable can fetch approximately thirty pounds, one in good condition can sell for well over one hundred pounds.

This Article Continues...