Hi Geoff,

Thanks for your thoughts.  I put my answers to several of your ideas in 
this one note, to save sending a bunch of separate replys.

 > Cold Solder Joint  someplace ???

Chris Chapman made a similar suggestion, and I really can't rule it our 
absolutely.  But Larry's bards are very well constructed and probably 
were wave soldered.  So I don't think it's too likely.  At one time I 
actually did try reheating a couple of connections that looked a little 
suspicious, but it didn't make any difference.


 > Im no expert, but Id not use electrolytics in any circuits but power 
circuits.

The old fashioned "electrolytics" are pretty much a thing of the past.  
I think that good quality newer tantalums are fine.  In any event, I 
don't know what else you would use to get 47mf in a reasonable size 
package.  I is true though that some computer mother boards fail due to 
cheap capacitor syndrome.  I've seen photos of boards where several caps 
were bulging and leaking.  But I don't see anything like that on my board.


 > really really tiny wires >= AWG 30 are fine for dc but resist the 
intrusion of ac and at the same time seem to reduce feedback coupling 
between inputs and outputs. they are fine for > passive seismic stuff 
like velocity geophones. skin effect at higher frequencies make such a 
thing so.
 > ac will flow in thinner and thinner depths of the wire as F goes up. 
makes for HIGH Z with AC and low R with DC, or so it seems to me.

I am familiar with the skin effect you are alluding to.  But it is only 
significant at RF frequencies.  And there really aren't any super fine 
wires in my system, other than in the damping coil.

Larry
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