Theoretical physics 
Nah, just straight design engineering. The problem is the published specs, user documentation, and actual unit markings on the machines are more often handled by the sales & marketing departments. Actually the real source of the problem is that the target customer for these devices doesn't care what the actual specs are. They just want an inexpensive recorder which fits their mental concept of "good", sounds decent and works reliably, whether it's actually measurably good or not. And there's nothing wrong with that.
Specs for gear marketed to professionals is usually much better documented, or you can at least contact them and actually find out what ever you need to know. But determining the usage specs for gear sold to the prosumer or enthusiast market or whatever one cares to call it more often than not comes down to someone with decent test gear getting a hold of the recorder, bench-testing it, and posting the applicable specs here or on some other website.
In general, we as tapers land somewhere between the pro users and the point-n-shoot commercial users, both in the specifications useful to us and in our understanding of them!
As noted in other threads from time to time "line-in" does not even necessarily mean a straight unprocessed signal. Most of those cross the pre-amp circuitry too.
I was really surprised when I read a ts.com post that someone's inquiry directly to Sound Devices confirmed that the line-in setting on the Sound Devices 7XX series doesn't bypass the pre-amps.
What is a "straight unprocessed signal"? a direct pin-in to the ADC?
Refer to it as an "input buffer with gain" rather than a "preamp section" if that makes you feel better about it.
When I see "line-in" that says to me, "an input which does not provide any sort of microphone powering, typically for a source with an output level that can be higher than a typical microphone level input". To figure out how hot that input signal can be, or where the input noise floor is, or how the input sensitivity relates to another piece of equipment, I need the specs. I don't care what's inside, only it's parameters, how it sounds, its reliability, etc.
It's is actually an ironic confirmation of all this stuff. What truly maters for us as end users is the actual performance specs, partly just for proper interfacing of gear, but those things are described by numbers and terminology which many end users don't know how to interpret. What doesn't really matter at all very much is how it's achieved- the engineering stuff and whatever labels describe the circuitry inside. So what if it bypasses preamps, uses discrete transistors, thermionic valves, magnetic core memory, trained circus fleas on miniature hamster-wheels or whatever. Well, the design engineers care, the circuit-geeks do, the recorder company accountants do, but the end user shouldn't really give much of a hoot as as long as the thing works to specification, sounds good, and is reliable. It quickly degrades in to audiophile bs of what people think is important when it isn't necessarily- "this one uses such-and-such a chip, with a discrete "blah, blah, blah" wired with pure-silver twisted unicorn hair insulated whatevers.
Eh, whatever. I guess I'm just not a very good gearslut at heart. I dig the recordings way more than the gear. Measure it, listen to it, beat it up. If it does the job well, reliably, and predictably who cares what's inside?
Topic: Question On Specs (Read 5350 times)