Note: Reducing Switch Tension

[NightFlight]

My attenuator switches came with four leafs each. 2 per side. I found removing one side as directed for lighter action resulted in intermittent connectivity in one channel. In my case it was the fine control of -4.5db through to -7.5db on the right side only.   This appears to be because (in at least one of my switches) this was enough to increase the amount of lateral movement in the switch shaft.

Restoring one of the leafs per side and keeping both bearings installed has achieved the same lighter action and eliminated the lateral play problem.  I would recommend the build guide reflect this option. 

This is also all very likely easier to do before the resistors are soldered in. 

[JamieMcC]

Interesting I just mounted my attenuator switches today and was planning to make a start on the hook up tomorrow after reading your post I will have a little play with the switches tomorrow.
 
Whilst testing for the switch number of positions they did not seem overly stiff but it would be a good test to see if a lighter action is preferable.

[NightFlight]

I though the same until I started using it for a while. You know the tension is high when in the dark, your uncertain which position the switch is in and you apply enough pressure to suddenly realize:

 a) there were no more positions on the fine.
 b) you have to reset the set screw.

[JamieMcC]

After a little experimentation I decided to keep mine standard I do like the quality of the switches the make before break action during switching is very quiet through the phones during operation (wonder what brand they are) I did like the lighter feel after removing one of the leafs but felt the indexing of each step had a more noticeable rolling feel to it in comparison. I could happily live with either set up but thought I would see if the two leaf configuration might lighten with some use.

[Grainger49]

   .  .  .    b) you have to reset the set screw.

I'll make a suggestion to help this situation.  Position the knob as you like it and either tighten the screw enough to mark where it is or carefully remove it and mark it with a pencil.  Remove the knob and take a small file and file down the shaft where the set screw will settle into the relief.

What scares me about this is that you have a very nicely finished Mainline and you don't want to scar up the top plates.

[NightFlight]

Thanks. I'll save the notch for when I order some nicer knobs.