Eminent Technology ET-2 Tonearm Owners

Hi Mkiser - (Mark)  ? 
long time since hearing from you. ;^)

Pic 35 on my my virtual system shows how to set the gap with the tonearm not mounted.. You can see on the feeler gauge in the pic, that I have it set quite firm. I also do not find a need to use the VTA much. I aim to keep the manifold inscribed line even with the record. 

Here are some comments from Bruce that should help. I had to dig into email archives from 2014.

Chris,

  The gap is suggested so that the bearing blocks are parallel to the manifold housing, the gap value is arbitrary. I would not force a bearing block too close to the manifold housing such that the friction to adjust VTA is high, doing so would damage the arc block. The bearing block screw length is the same on all tonearms, 4-40 x 3/4 for the bottom pair and 4 x 40 x 5/8 for the top pair.
  We no longer sell VTA arc blocks as an individual part. I hope this helps.

    brucet


Chris,

    My first rule would be to use the short end of the Allen wrench as the lever for torquing any screws on the ET-2. The short lever arm will limit the applied torque.
    For the two bearing blocks that mesh the pinion to the rack in the arc block we first adjust the blocks so that they are parallel to the manifold housing with a .060 -.090 gap between the bearing block and the back adjacent surfaces on the manifold housing.
    The friction between the manifold housing and the arc block define the feel of the VTA mechanism lever action. We want this to offer some resistance, but not too much when a VTA adjustment is attempted. Turn the 4/40 x 3/4 bearing block screws so that some friction is encountered when adjusting VTA but not so much that the VTA mechanism locks up. We would not attempt this adjustment with the tonearm installed on a turntable.
   
  The main failures we see with the arc blocks are:
  1.The threaded insert on back surface of the arc block is cracked due to over torquing of 8-32 stainless steel button head post mounting screw.
  2.The bearing blocks on either side of the arc block which support the pinion gear are over torqued which crushes the pinion into the rack and binds the mechanism, if a VTA change is attempted with over torqued bearing blocks the pinion turns and the rack does not move, stripping the teeth on the rack.
    - brucet

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Mkiser

I've had this setup sounding really good, and for a while the new Zephyr was spot on, more like listening to a master tape than an LP.

Re: Master tapes reference.
I still own a Studer and some 15 IPS master tape dubs. When I first brought it home many years ago it was a great reference for me and it still is. Over time, and tweaking, I have my main vinyl rig competing and out performing some of the tapes in my room. The good ones (tape) are just really good, and I also don't have LPs for some of the tapes.  

Cheers Chris

Hi Mkieser! I assume you checked this, but in case not...
It's quite easy to upset the lateral balance of the arm while changing cartridges or arm wands. Did you carefully check levelness?I had issues with levelness even when using the VTA adjustment. So my recommandation is to always recheck for levelness after changing the VTA, or touching the VTA adjustment. And I think changing a cartridge or arm wand would apply for the same.
Horizontal off-levelness skews the tonality of the cartridge and deteriorates bass quality to a surprising the degree.
Another variable for somebody with a good aural memory is the tightness of all used screws and connections.IME lowest possible torque sounds best. I use only as much as to prevent slipping of the connections or the cartridge.
Your opinion might vary, but at least play and check these things.

Thanks for the responses.  I'm going to revisit my setup yet again this evening and get back.  It's a lot to take in.  At some point I'll update my virtual system with more recent pics of my turntable.  I've made a few tweaks that I haven't seen mentioned in this forum. 

BTW it's Mike Kiser.  Just jumping in to say that I've posted some turntable and tonearm pictures in my virtual forum.  Amp and speakers are in a state of flux, so for now it's just turntable pictures.  As long as I'm here I just want to thank you guys for your insights over all the years.  I haven't solicited much advice directly but have followed a lot of the threads with interest.  Probably the thing I've learned most from this forum is the importance of balance, and the wonderful? world of I beams and leaf springs.  FWIW, I'm going to be sending my manifold, spindle and manifold housing back to Bruce soon.  There is an air flow imbalance that causes the spindle to push in one direction as I increase pressure. It was pushing out. I flipped the manifold and sure enough it started pushing in as I increased pressure.  I contacted Bruce and he told me to send it in for balancing.  I'm not sure I've seen anyone else mention this issue, so just wanted to put it out there. 

I’m going to be sending my manifold, spindle and manifold housing back to Bruce soon. There is an air flow imbalance that causes the spindle to push in one direction as I increase pressure. It was pushing out. I flipped the manifold and sure enough it started pushing in as I increased pressure.

Mike.
This is interesting.
My understanding is that the stock 2.0 smaller lighter spindle needs about 3 psi to levitate. The larger heavier lower resonance stock 2.5 spindle, designed for MC carts, needs in the neighborhood of 5-6 psi to do the same thing. This is for Bruce’ stock builds. Then we get into the custom builds that Bruce has done for clients, like myself. He set my 2.5 up for 19 PSI. In discussions with him at the time it was my understanding that this is the PSI limit for the design.

So based on the above, why are you choosing to increase the PSI ? and does the spindle stays balanced, when it is run at the PSI that Bruce set the manifold up for at his shop ?

Just thinking out loud over coffee this morning.

If I were located far from Bruce in Florida, and the (spindle, manifold) were going to be sent to him for maintenance anyway; I would first be tempted to try rebalancing the manifold on my own. As you are using direct shot wiring set it up without the wiring and just the spindle on (Look Mom, no wires ! - hah hah )

So with just the spindle on, turn on the air at the factory set PSI. Do observations. Now bump up the pressure and observe again. Slide out the manifold itself, and adjust the screws on the one side a bit, on the side it it pushes towards. Open them up a bit equally. What happens ? If it gets worse turn them in again and go to the other side and repeat. Again, just something to try, before it goes back to Bruce.

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lots of turntable tweaks in your Audiogon page.
I really like the way you have set up the thread/floss on your turntable. Interested in the differences you heard compared to the belt setup.