In this older article, I undertook the restoration of a lovely Technics SL-120 direct-drive turntable. Let’s check out this repair.
The Technics SL-120 is basically an SL-1200, without a tonearm. Owners often chose to fit an SME 3009, as was the case with this old deck. This a quality direct-drive deck, featuring a brushless DC motor providing several notable advantages over belt-drive decks.
There is no belt or transmission to introduce noise and irregularities of motion. A motor that is ultimately locked to a quartz crystal, means the deck is not subject to mains fluctuations as AC motor belt-driven decks are. Direct coupling of the platter to the motor effectively makes that the platter and motor rotor one giant motor!
The SL-120 is not quite as heavily-built as the SL-1200, but nevertheless this is a solid deck, weighing in at 10 kg, with 1.75 kg of platter mass, just like the SL-1200. The deck features a strobe, with vernier speed adjustments possible via small knobs at the front left of the chassis. Speed change is effected by a lever.
This particular SL-120 exhibited several issues, notably the SME 3009 arm was in very poor shape with almost everything loose, broken or misadjusted. The motor bearing was dry and desperately in need of some oil.
The chassis was also filthy and the lid was not attached properly at the back and the speed controls were not working properly and were very stiff. the strobe seemed to be operating only intermittently as well.
Basically I fixed the headshell wires and resoldered a couple of cartridge clips. I thoroughly cleaned the arm as you will see in the photos and attached a nice new Ortofon 2M red cartridge. I opened her up and cleaned the speed adjustment pots, speed switch, cleaned the whole chassis and lubed the motor.
In relation to the SME 3009, some work was required there and this needs to be factored in if you are planning similar work yourself. Soldering cartridge clips requires a fine soldering iron, a low – moderate tip temperature and a very steady hand, along with an ‘assistant’ in the form of a small vice or soldering assistant.
In terms of the mechanical components of the arm, almost everything is adjustable on the 3009, and most of these adjustments will be set up incorrectly in my experience. You have to set the lateral balance, stylus downforce, anti-skate, damping paddle, arm ride height and overhang. All of this must be set precisely, in order to extract maximum performance from this venerable tonearm.
After working through the issues, the SL-120 came up beautifully and her owner was very happy. I can certainly recommend the technics SL-120 as a great mid-range deck, that should give years of reliable service and offer many advantages over cheap new belt-drive decks.
If you want more reading on the Technics SL-120, or the owner’s or service manuals, visit the Vinyl Engine!