Chris
I built this version of the ET2 around 15 years ago. Drawings are long gone but it could be reverse engineered. The arm is optimized for low compliance carts. As you can see, just, from one of the pics Ketchup found, it has a fixed counterweight. I have a view on linear arms in that the rules for pivoted arms and effective horizontal mass do not apply. In fact I have added a lead slug inside the bearing spindle 25 mm long with its OD equalling the ID of the tube. This is glued in place halfway along its length. ( it can be removed if I go to high compliance carts)
This combined with the fixed counterweight means that the arm is HEAVY in the horizontal plane. I have tried magnetic dampening and oil troughs but prefer the pure mass approach. I run at around 12 psi, lower pressures may be problematic when adding so much mass.
On the magnetic dampening front the negative I heard was possibly caused by the induced circulating currents interfering with the cartridge output
The manifold and arm pillar are made from acrylic. Lead is inserted and epoxy glued inside these to sink energy. VTA is adjusted by a removable screw after loosening 4x M5 cap screws. Manifold and pillar are locked solid once these are tightened. The arm was designed with a lifter like the ET but I found a subtle improvement when this was removed. Same goes for the VTA adjustment screw. I. E in its operating form there are no bits to flop about. Arm pillar is fused to the plinth effectively making it one assembly.
Cartridge leads are single strand silver lightly twisted at about one turn per 8 mm. Continuous to the preamp
Big jumps in performance were the goose neck. (This was made from the same grade of aluminum as the wand.) The bracket that joins the wand to the spindle.
There are 2x M2 grub screws outboard of the bearing sleeve orings. These pass thru the manifold and contact the sleeve. Two small pieces of shim metal are inserted at 120 degree increments away from the grub screws. Once tightened the grub screws eliminate the compliance of the orings. There should be nothing soft in the loop between record and cartridge. This is a major improvement. There may be room on the standard manifold to do this but Beware anyone doing this it would be easy to break the manifold.
I use 2x 50 liter containers for the surge tanks. They are stuffed with long hair unspun wool to increase their effective volume. They are seperated by 6 meters of 1/4 hose entry and exit points are at opposite ends of these tanks.
Chris you have a regulator, water separator. It looks like it uses brass fittings and appears to be close to the arm. Try soldering a wire to the exit fitting and earthing this. I don't know why this works but it is possibly something to do with static electricity build up in the air stream.
On the topic of static electricity try rubbing the wand with AFC anti static foam cleanser. The stuff they use on photocopier glass.
Have removed the Teflon in the head shell and replaced with a square of 1/2 mm thick lead and superglued in place. Others have tried different materials here also with good results.
I have a new arm on the drawing board based on what I have learnt from this one.
I built this version of the ET2 around 15 years ago. Drawings are long gone but it could be reverse engineered. The arm is optimized for low compliance carts. As you can see, just, from one of the pics Ketchup found, it has a fixed counterweight. I have a view on linear arms in that the rules for pivoted arms and effective horizontal mass do not apply. In fact I have added a lead slug inside the bearing spindle 25 mm long with its OD equalling the ID of the tube. This is glued in place halfway along its length. ( it can be removed if I go to high compliance carts)
This combined with the fixed counterweight means that the arm is HEAVY in the horizontal plane. I have tried magnetic dampening and oil troughs but prefer the pure mass approach. I run at around 12 psi, lower pressures may be problematic when adding so much mass.
On the magnetic dampening front the negative I heard was possibly caused by the induced circulating currents interfering with the cartridge output
The manifold and arm pillar are made from acrylic. Lead is inserted and epoxy glued inside these to sink energy. VTA is adjusted by a removable screw after loosening 4x M5 cap screws. Manifold and pillar are locked solid once these are tightened. The arm was designed with a lifter like the ET but I found a subtle improvement when this was removed. Same goes for the VTA adjustment screw. I. E in its operating form there are no bits to flop about. Arm pillar is fused to the plinth effectively making it one assembly.
Cartridge leads are single strand silver lightly twisted at about one turn per 8 mm. Continuous to the preamp
Big jumps in performance were the goose neck. (This was made from the same grade of aluminum as the wand.) The bracket that joins the wand to the spindle.
There are 2x M2 grub screws outboard of the bearing sleeve orings. These pass thru the manifold and contact the sleeve. Two small pieces of shim metal are inserted at 120 degree increments away from the grub screws. Once tightened the grub screws eliminate the compliance of the orings. There should be nothing soft in the loop between record and cartridge. This is a major improvement. There may be room on the standard manifold to do this but Beware anyone doing this it would be easy to break the manifold.
I use 2x 50 liter containers for the surge tanks. They are stuffed with long hair unspun wool to increase their effective volume. They are seperated by 6 meters of 1/4 hose entry and exit points are at opposite ends of these tanks.
Chris you have a regulator, water separator. It looks like it uses brass fittings and appears to be close to the arm. Try soldering a wire to the exit fitting and earthing this. I don't know why this works but it is possibly something to do with static electricity build up in the air stream.
On the topic of static electricity try rubbing the wand with AFC anti static foam cleanser. The stuff they use on photocopier glass.
Have removed the Teflon in the head shell and replaced with a square of 1/2 mm thick lead and superglued in place. Others have tried different materials here also with good results.
I have a new arm on the drawing board based on what I have learnt from this one.