I spoke with Oliver Archut on the phone today. The preamp fixes are going slowly because (my take on it):
1) He is working on them for nothing, out of friendship for Terry and Chance.
2) He is
very busy with his own work, from which he derives his income, particularly the mics, so he tries to do the ACMP stuff in spare moments. He's tried to get help, but no one/wives want to live in Kansas.
He could get some help from Europe, but Kansas won't allow work visas due to the high local unemployment.
3) Some parts needed to be bought, and he's been able to use some money from the Bulldog transformer income for this, but the cost of any fixes is still an over-riding concern.
4) As he has stated, the units are/will be going through a long burn in, to make sure the fixes are stable and won't come back to bite him in the ass.
The fixes appear to be a) shielding the power transformer, and b) replacing the bad transistors on the eq boards. The inductors will not be shielded. Although not discussed, I assume the "gain pop" will be fixed, though losing a gain position, by moving a resistor on the board, as previously discussed (oh so far back in this thread and elsewhere.)
My own experience is that he quality control on these was non-existent, so each unit has to be evaluated and treated individually, which takes more time. Of the
two preamps I have worked on, I found a cable unconnected (no signal), a jumper pc board not completely plugged in, a fuse jammed at an angle into the holder, a washer trapped under some components on the preamp board, and multiple deteriorating resistors.
I know it's been a long wait for those who sent in their pres to be part of this exploratory phase, but I sent one of mine (and some money) to Steve Hogan two years ago this month as a "guinea-pig" and have yet to receive anything back but a string of empty promises.
If I've got any of this wrong, Terry and Oliver please correct me. Again I commend all concerned for standing behind these. It has certainly taken its toll.