Arm conversion

[diviy]

I have non improved
SME 3009 with detachable
Head shell is it possible
To fit a 3012 arm tube to it ?

[Barry]

I have non improved
SME 3009 with detachable
Head shell is it possible
To fit a 3012 arm tube to it ?

Yes, it is possible.

First you have to remove the counterweight assembly from the rear of the 9" arm tube.

Second, desolder the 5 wires of the 9" arm tube from the Belling Lee connector at the base of the arm (make a note of which colour wire connects to a specific socket way of the connector).

Third, remove the yoke covering the horizontal knife-edge bearings, by removing the screws on each side of the yoke. The 9" arm tube can now be pulled out free.

Fourth, now replace with the 12" arm tube, passing the wires down through the hole in the vertical bearing.

Fifth, replace the vertical bearing yoke cover, and resolder the wires to the connector at the base of the arm.

Unless you have the heavier counterweight assembly for the 12" arm, you will be limited to the number of cartridges you can use. This is because the 9" arm counterweight only has a mass that is ~ 75% of that for the 12" arm.
But unless you want to use heavy cartridges such as an Ortofon SPU, you can probably get away with simply placing the counterweight nearer to the rear end of the armtube. (This will increase the effective mass of the arm and reduce the arm/cartridge resonant frequency.)

[diviy]

Thanks Barry I can have a counter weight made would this be a good upgrade to do ?

[Barry]

It depends on the exact cartridge you wish to use in the 12" arm.
But if you want a new counterweight made I would approach Steve at Magna Audio, a Member here who can turn up brass counterweights. I expect Steve could make a new counterweight having the same diameter but 4/3rds the length of the one you have. The lateral balance arrangement need not be changed: you can keep the original hardware.

Have a word with Steve, describing exactly what it is you want.