Well, it's gratifying & heartening to enjoin such company.
The situation I've been battling for 3 years (!!) is an instrument that measures absorption in media.
The original object was designed in the late 1950s. It uses a Wheatstone bridge with 2 photovoltaic cells as sensors.
The cells/sensors are connected head to tail with a potentiometer to balance them as Reference & Sample sensed values.
Operator then offsets/reduces the Reference value with a specified value, and gives the Sample its' contamination,
the results' end point is the time it takes for the contamination to cause the Sample
to absorb enough to match the Referenced specified offset value.
(sorry to be vague on operation, customer is kind of touchy on that)
The 1950s designs' components are either not available and/or silly expensive.
Ergo, I was commissioned to design a modern equivalent.
What's been mentally blocking me was the thinking that the bridge actually needed to behave with + & - voltages.
While true, but if only that the common point (head<->tail opposite end of balancing pot) is locked to 0.00VDC.
The popping sound you (may) hear is the cranial-sphincterectomys' result of just pushing that common point
enough above 0.00VDC such that the reference sensor is >0.00VDC as well (DUH).
Now I can use all conventional amps, don't need protection limiters on uC ADC inputs.... Massive DUH.
I'm not looking for design critique on this project (unless this recent approach is faulty [again]).
What I'm going after with (collectively) you, is to not need the "popping" sound... I bounce a concept off "you" and you critique it.
I'll be More than willing to do the same (you may have observed my missives.. while not kind, I think fair).
That this is 3 years/8 analog designs proves I'm not worth a stink at analog.
I'll counter that in digital hdwe & assembler level swre, I make up for this... (but that's My story..)
Thanks for "listening", tip your waitress (to the left), I'll be here all week....... G.H. <<<)))