Shure sme tonearm grommets
#Shure sme tonearm grommets free
You need a free hand to hold the motor as its still connected by wires, and quite heavy - its well built. It's easy to unscrew the threes rods and detach the the motor from the top plate. I'll leave in the section below describing how I restored the originals, but for best results try these: I know from the PL12D facebook group that these are excellent and remove the hum completely.
An enterprising gentleman in Sweden, Tom Silvennoinen, is selling new replacement rubber mounts made of modern silicon rubber and cast to the right size, and are a fair price. These rubber bushes can become hardened over time and this diminishes their ability to absorb the mechanical vibration from the motor, which gets picked up by the cartridge as a background hum. Note the black rubber bushes, which the motor sits on via the three threaded rods. In the inverted picture above you can see the motor. This appears to be a very common problem with the PL-12D. This was probably the cause of the problem the previous owner described where the deck would bounce around at the slightest nudge. On inspection these were crumbling as can happen to foam rubber over time, and I discarded these to be replaced with new pieces of foam later. In the picture above you can see one of the 4 springs described in 1) with the foam plug still present. You will see that beneath the motor is a mesh vent to allow some air circulation as the motor can get hot.ĥ) the record is decoupled from the platter by the rubber mat. Technically there are 5 systems used in the PL-12D:ġ) The metal top plate is decoupled from the wooden plinth via 4 springs, which have foam rubber dampers, rather like the suspension and shock absorbers in a carĢ) The motor is decoupled from the top plate by sitting on 3 rubber bushes via 3 retaining rodsģ) The motor is decoupled from the platter via the drive beltĤ) The deck sits of 4 rubber feet, though these are minimal in effect and are primary for grip and to allow air flow beneath the deck. The motor is one source of vibration, the surrounding environment is another. All turntables include some degree of decoupling i.e springiness, to isolate sources of vibration from the arm and platter. Also the motor made a bit of a knocking sound, again, possibly a lubrication issue, so a simple service seemed a good idea.Īs music is extracted from a record by transforming microscopic vibrations back into electrical signals, errant vibrations are hence the enemy of good vinyl replay. While the platter rotated, removing the platter and then turning the spindle by hand was hard, indicating maybe the grease had dried up. Both the 45 RPM adapter and the additional screw-in balance weight (for heavier cartridges) were both included, and it came with a classic Shure M75HE Mk 2 cartridge. The deck in question was in great condition, and very complete. Many Japanese belt drive decks throughout the 1970's shared very similar construction, so this may be of interest even if your deck is not a PL-12D. While this blog is specifically about this particular model of deck, many of the concepts are similar to others from this vintage. I have previously worked on one of these decks, and know what she means about the suspension system used.
The lady who offered it, said that she in turn had received it from freecycle, and had replaced the belt but couldn't get on with the springiness of it, and had got a modern USB turntable. Last week I was lucky enough to get a Pioneer PL-12D turntable from freecycle. In most cases they have required a little work to get them running again.
I keep a few, some end up passed onto friends, some that are too far gone are kept for spares. I have a number of turntables (NAD 5120, Ariston QDeck, Pioneer PL12D ) which I got also second hand. I got back into vinyl records about 18 months ago, and have collected a few hundred albums, mostly second hand.