So, am I reading that it seems most of the people in thread so far are asking for a simple analog-only preamp?
If a thought early in the thread of possibility of digital inputs still has traction (and would be paired with analog outputs), and the volume control that has been floated around (no pun intended with the FPGA comment) is something that by design is done in the digital domain (reprocessing the original signal, whether done D-D or A-D before being converted D-A for the outputs), unless I'm missing something, all that kind of requires a DAC, and if a DAC needs to be in there anyway, it seems counterproductive not to use a GOOD one (Tommy's words)? Having digital inputs to that DAC in the device simply means that Tommy's "most recommended" signal path (digital source - digital volume control - DAC - analog amplifier output stage) would be available, with the "added feature" (as an analog preamp) to be able to take input from analog sources (phono stages, tapes, someone's favorite outboard DAC...) as well (analog source - internal ADC - digital volume control - DAC - analog amplifier output stage)?
Although it sounds like there is some interest by people posting in this thread for an analog preamp, maybe some of your existing (amplifier) customers looking to go all-in on your design philosophy are really looking for a more fully-featured integrated than the STM (or at least an equivalent "preamp" section in a case that could be connected to their already purchased outboard amps) with a few more analog inputs for those still using something other than a single, non-digital source?
...or maybe I'm over thinking this and I should just let Tommy put together a nice analog input switcher with an impedance buffer and remote volume control and call it a day.
(As an aside, on what seems to be Tommy's common thread of streamlining and shortening signal paths, I'm wondering out loud why there hasn't been produced a DAC DAC 1.5 that builds the USB-SPDIF converter into the DAC itself, thus allowing the shortest possible signal path (no external connectors or variables in cabling) from a USB input to the DAC DAC's native (SPDIF?) input?)
(Taken a step further, starting with the "all pieces are already in place" starting point, it doesn't seem much of a stretch to build an all-digital "integrated" that puts the "most recommended configuration" all in one box, maybe adding a digital volume control so as to not rely on a variable in the quality of digital volume control at the source? It kind of seems to be more in line with industry trends - DACs that include volume control/"preamp" functionality, or fully integrated software driven digital solutions - but I might be completely wrong. Is the DAC/pre still the "in" thing or is the industry leaning more in the direction of streamer/source/pre so that DACs can be changed more easily at will/whim?)