what if all the pots are replaced with new ones without taps, no ldns sw. no tape sw, no tape in/outs just line/cd and phono ins and new rotarys. that was my plan to do. but ti sounds like theres other things need fixing or changing to correct gain defects and all. lots more than I had planed to do. and then it will hum probably anyway.
It just sounds like a big headache at this point. maybe I need to put it down for 6 mos and come back later. with a new perspective. O' decisions decisions.
I removed all the stuff you mentioned in your things to do list, If you do take all that stuff
out of your HF-85 you will gain a lot of room in your chassis and that will make it easy
to re-wire all the tube heater filaments wires further away from other components, I also
ran the AC in line in at the corner where the transformer is and removed the AC power
on/off switch up at the front of the pre, I just use a power strip to turn on the HF-85 and
the Magnavox 9303 amp thus keeping the 120 AC volt wires short and direct to the
transformer.
I also used a lot of shielded wires and grounded one end of the outer conductor to chassis
ground, you can get these units very quiet and still keep AC on the filaments and once
you remove all that stuff it will be easier then you think.
The alps volume pot helped mine a lot and I really like the way those pots feel and with
very nice tracking at low volume.
Most of you know that the tape out jacks are controlled by the volume pot and bypass the
tone circuit in these units, I think the sound is far cleaner sounding and definitely has
better detail in the music, so I don't even use the tone controls on the HF-85 and now
knowing how much better it sounds using those tape out jacks I would not have wasted
my time with the tone circuit and the PC boards I built for the tone controls.
I think it's worth the efforts you will put into it and yes that Eico HF-85 can run circles
around at lot of other preamps.